Author name code: dreizler
ADS astronomy entries on 2022-09-14
author:"Dreizler, Stefan" 
------------------------------------------------------------------------  

Title: The CARMENES search for exoplanets around M dwarfs: Stable
    radial-velocity variations at the rotation period of AD~Leonis --
    A test case study of current limitations to treating stellar activity
Authors: Kossakowski, D.; Kürster, M.; Henning, Th.; Trifonov, T.;
   Caballero, J. A.; Lafarga, M.; Bauer, F. F.; Stock, S.; Kemmer, J.;
   Jeffers, S. V.; Amado, P. J.; Pérez-Torres, M.; Béjar, V. J. S.;
   Cortés-Contreras, M.; Ribas, I.; Reiners, A.; Quirrenbach, A.;
   Aceituno, J.; Baroch, D.; Cifuentes, C.; Dreizler, S.; Forcada,
   J. S.; Hatzes, A.; Kaminski, A.; Montes, D.; Morales, J. C.; Pavlov,
   A.; Peña, L.; Perdelwitz, V.; Reffert, S.; Revilla, D.; Rodríguez
   López, C.; Rosich, A.; Sadegi, S.; Schöfer, P.; Schweitzer, A.;
   Zechmeister, M.
Bibcode: 2022arXiv220905814K
Altcode:
  Context: A challenge with radial-velocity (RV) data is disentangling
  the origin of signals either due to a planetary companion or to
  stellar activity. In fact, the existence of a planetary companion
  has been proposed, as well as contested, around the relatively
  bright, nearby M3.0V star AD Leo at the same period as the stellar
  rotation of 2.23d. Aims: We further investigate the nature of this
  signal. We introduce new CARMENES optical and near-IR RV data and an
  analysis in combination with archival data taken by HIRES and HARPS,
  along with more recent data from HARPS-N, GIANO-B, and HPF. Also,
  we address the confusion concerning the binarity of AD Leo. Methods:
  We consider possible correlations between the RVs and various stellar
  activity indicators accessible with CARMENES. We applied models
  within a Bayesian framework to determine whether a Keplerian model,
  a red-noise quasi-periodic model using a Gaussian process, or a mixed
  model would explain the observed data best. We also exclusively focus on
  spectral lines potentially associated with stellar activity. Results:
  The CARMENES RV data agree with the previously reported periodicity
  of 2.23d, correlate with some activity indicators, and exhibit
  chromaticity. However, when considering the entire RV data set,
  we find that a mixed model composed of a stable and a variable
  component performs best. Moreover, when recomputing the RVs using
  only spectral lines insensitive to activity, there appears to be
  some residual power at the period of interest. We therefore conclude
  that it is not possible to determinedly prove that there is no planet
  orbiting in synchronization with the stellar rotation given our data,
  current tools, machinery, and knowledge of how stellar activity affects
  RVs. We do rule out planets more massive than 27M_E (=0.084M_J). We
  also exclude any binary companion around AD Leo with Msini > 3-6M_J
  on orbital periods <14yr.

Title: The BlueMUSE data reduction pipeline: lessons learned from
    MUSE and first design choices
Authors: Weilbacher, Peter M.; Martens, Sven; Wendt, Martin; Roth,
   Martin M.; Dreizler, Stefan; Kelz, Andreas; Bacon, Roland; Richard,
   Johan
Bibcode: 2022arXiv220906022W
Altcode:
  BlueMUSE is an integral field spectrograph in an early development
  stage for the ESO VLT. For our design of the data reduction software for
  this instrument, we are first reviewing capabilities and issues of the
  pipeline of the existing MUSE instrument. MUSE has been in operation
  at the VLT since 2014 and led to discoveries published in more than
  600 refereed scientific papers. While BlueMUSE and MUSE have many
  common properties we briefly point out a few key differences between
  both instruments. We outline a first version of the flowchart for
  the science reduction, and discuss the necessary changes due to the
  blue wavelength range covered by BlueMUSE. We also detail specific
  new features, for example, how the pipeline and subsequent analysis
  will benefit from improved handling of the data covariance, and a more
  integrated approach to the line-spread function, as well as improvements
  regarding the wavelength calibration which is of extra importance in
  the blue optical range. We finally discuss how simulations of BlueMUSE
  datacubes are being implemented and how they will be used to prepare
  the science of the instrument.

Title: Precise mass determination for the keystone sub-Neptune planet
    transiting the mid-type M dwarf G 9-40
Authors: Luque, R.; Nowak, G.; Hirano, T.; Kossakowski, D.; Pallé, E.;
   Nixon, M. C.; Morello, G.; Amado, P. J.; Albrecht, S. H.; Caballero,
   J. A.; Cifuentes, C.; Cochran, W. D.; Deeg, H. J.; Dreizler, S.;
   Esparza-Borges, E.; Fukui, A.; Gandolfi, D.; Goffo, E.; Guenther,
   E. W.; Hatzes, A. P.; Henning, T.; Kabath, P.; Kawauchi, K.; Korth,
   J.; Kotani, T.; Kudo, T.; Kuzuhara, M.; Lafarga, M.; Lam, K. W. F.;
   Livingston, J.; Morales, J. C.; Muresan, A.; Murgas, F.; Narita, N.;
   Osborne, H. L. M.; Parviainen, H.; Passegger, V. M.; Persson, C. M.;
   Quirrenbach, A.; Redfield, S.; Reffert, S.; Reiners, A.; Ribas, I.;
   Serrano, L. M.; Tamura, M.; Van Eylen, V.; Watanabe, N.; Zapatero
   Osorio, M. R.
Bibcode: 2022arXiv220807287L
Altcode:
  Context. Despite being a prominent subset of the exoplanet population
  discovered in the past three decades, the nature and provenance
  of sub-Neptune-sized planets are still one of the open questions
  in exoplanet science. Aims. For planets orbiting bright stars,
  precisely measuring the orbital and planet parameters of the system
  is the best approach to distinguish between competing theories
  regarding their formation and evolution. Methods. We obtained 69
  new radial velocity observations of the mid-M dwarf G 9-40 with the
  CARMENES instrument to measure for the first time the mass of its
  transiting sub-Neptune planet, G 9-40 b, discovered in data from the
  K2 mission. Results. Combined with new observations from the TESS
  mission during Sectors 44, 45, and 46, we are able to measure the
  radius of the planet to an uncertainty of 3.4% (Rb = 1.900 +- 0.065
  Re) and determine its mass with a precision of 16% (Mb = 4.00 +- 0.63
  Me). The resulting bulk density of the planet is inconsistent with a
  terrestrial composition and suggests the presence of either a water-rich
  core or a significant hydrogen-rich envelope. Conclusions. G 9-40 b is
  referred to as a keystone planet due to its location in period-radius
  space within the radius valley. Several theories offer explanations
  for the origin and properties of this population and this planet is a
  valuable target for testing the dependence of those models on stellar
  host mass. By virtue of its brightness and small size of the host, it
  joins L 98-59 d as one of the two best warm (Teq ~ 400 K) sub-Neptunes
  for atmospheric characterization with JWST, which will probe cloud
  formation in sub-Neptune-sized planets and break the degeneracies of
  internal composition models.

Title: Detailed stellar activity analysis and modelling of GJ
    832. Reassessment of the putative habitable zone planet GJ 832c
Authors: Gorrini, P.; Astudillo-Defru, N.; Dreizler, S.; Damasso,
   M.; Díaz, R. F.; Bonfils, X.; Jeffers, S. V.; Barnes, J. R.; Del
   Sordo, F.; Almenara, J. -M.; Artigau, E.; Bouchy, F.; Charbonneau,
   D.; Delfosse, X.; Doyon, R.; Figueira, P.; Forveille, T.; Haswell,
   C. A.; López-González, M. J.; Melo, C.; Mennickent, R. E.; Gaisné,
   G.; Morales Morales, N.; Murgas, F.; Pepe, F.; Rodríguez, E.; Santos,
   N. C.; Tal-Or, L.; Tsapras, Y.; Udry, S.
Bibcode: 2022A&A...664A..64G
Altcode: 2022arXiv220607552G
  Context. Gliese-832 (GJ 832) is an M2V star hosting a massive planet on
  a decade-long orbit, GJ 832b, discovered by radial velocity (RV). Later,
  a super Earth or mini-Neptune orbiting within the stellar habitable zone
  was reported (GJ 832c). The recently determined stellar rotation period
  (45.7 ± 9.3 days) is close to the orbital period of putative planet
  c (35.68 ± 0.03 days). <BR /> Aims: We aim to confirm or dismiss
  the planetary nature of the RV signature attributed to GJ 832c, by
  adding 119 new RV data points, new photometric data, and an analysis
  of the spectroscopic stellar activity indicators. Additionally, we
  update the orbital parameters of the planetary system and search
  for additional signals. <BR /> Methods: We performed a frequency
  content analysis of the RVs to search for periodic and stable
  signals. Radial velocity time series were modelled with Keplerians
  and Gaussian process (GP) regressions alongside activity indicators
  to subsequently compare them within a Bayesian framework. <BR />
  Results: We updated the stellar rotational period of GJ 832 from
  activity indicators, obtaining 37.5<SUP>+1.4</SUP><SUB>-1.5</SUB>
  days, improving the precision by a factor of 6. The new photometric
  data are in agreement with this value. We detected an RV signal
  near 18 days (FAP &lt; 4.6%), which is half of the stellar rotation
  period. Two Keplerians alone fail at modelling GJ 832b and a second
  planet with a 35-day orbital period. Moreover, the Bayesian evidence
  from the GP analysis of the RV data with simultaneous activity indices
  prefers a model without a second Keplerian, therefore negating the
  existence of planet c. <P />Activity indices, photometric and RV
  time series are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/664/A64">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/664/A64</A>

Title: The HD 260655 system: Two rocky worlds transiting a bright
    M dwarf at 10 pc
Authors: Luque, R.; Fulton, B. J.; Kunimoto, M.; Amado, P. J.; Gorrini,
   P.; Dreizler, S.; Hellier, C.; Henry, G. W.; Molaverdikhani, K.;
   Morello, G.; Peña-Moñino, L.; Pérez-Torres, M.; Pozuelos, F. J.;
   Shan, Y.; Anglada-Escudé, G.; Béjar, V. J. S.; Bergond, G.; Boyle,
   A. W.; Caballero, J. A.; Charbonneau, D.; Ciardi, D. R.; Dufoer, S.;
   Espinoza, N.; Everett, M.; Fischer, D.; Hatzes, A. P.; Henning, Th.;
   Hesse, K.; Howard, A. W.; Howell, S. B.; Isaacson, H.; Jeffers, S. V.;
   Jenkins, J. M.; Kane, S. R.; Kemmer, J.; Khalafinejad, S.; Kidwell,
   R. C.; Kossakowski, D.; Latham, D. W.; Lillo-Box, J.; Lissauer, J. J.;
   Montes, D.; Orell-Miquel, J.; Pallé, E.; Pollacco, D.; Quirrenbach,
   A.; Reffert, S.; Reiners, A.; Ribas, I.; Ricker, G. R.; Rogers, L. A.;
   Sanz-Forcada, J.; Schlecker, M.; Schweitzer, A.; Seager, S.; Shporer,
   A.; Stassun, K. G.; Stock, S.; Tal-Or, L.; Ting, E. B.; Trifonov,
   T.; Vanaverbeke, S.; Vanderspek, R.; Villaseñor, J.; Winn, J. N.;
   Winters, J. G.; Zapatero Osorio, M. R.
Bibcode: 2022A&A...664A.199L
Altcode: 2022arXiv220410261L
  We report the discovery of a multiplanetary system transiting the
  M0 V dwarf HD 260655 (GJ 239, TOI-4599). The system consists of at
  least two transiting planets, namely HD 260655 b, with a period of
  2.77 d, a radius of R<SUB>b</SUB> = 1.240 ± 0.023 R<SUB>⊕</SUB>,
  a mass of M<SUB>b</SUB> = 2.14 ± 0.34 M<SUB>⊕</SUB>, and a bulk
  density of ρ<SUB>b</SUB> = 6.2 ± 1.0 g cm<SUP>−3</SUP>, and HD
  260655 c, with a period of 5.71 d, a radius of {R_c} = 1.533<SUB> -
  0.046</SUB><SUP> + 0.051</SUP>{R_ \oplus }, a mass of M<SUB>c</SUB> =
  3.09 ± 0.48 M<SUB>⊕</SUB>, and a bulk density of {ρ _c} = 4.7<SUB>
  - 0.8</SUB><SUP> + 0.9</SUP>{{g}} g cm<SUP>−3</SUP>. The planets
  have been detected in transit by the Transiting Exoplanet Survey
  Satellite (TESS) mission and confirmed independently with archival
  and new precise radial velocities obtained with the HIRES and CARMENES
  instruments since 1998 and 2016, respectively. At a distance of 10 pc,
  HD 260655 has become the fourth closest known multitransiting planet
  system after HD 219134, LTT 1445 A, and AU Mic. Due to the apparent
  brightness of the host star (J = 6.7 mag), both planets are among the
  most suitable rocky worlds known today for atmospheric studies with
  the James Webb Space Telescope, both in transmission and emission.

Title: VizieR Online Data Catalog: GJ 832 stellar activity (Gorrini+,
    2022)
Authors: Gorrini, P.; Astudillo-Defru, N.; Dreizler, S.; Damasso,
   M.; Diaz, R. F.; Bonfils, X.; Jeffers, S. V.; Barnes, J. R.; Del
   Sordo, F.; Almenara, J. -M.; Artigau, E.; Bouchy, F.; Charbonneau,
   D.; Delfosse, X.; Doyon, R.; Figueira, P.; Forveille, T.; Haswell,
   C. A.; Lopez-Gonzalez, M. J.; Melo, C.; Mennickent, R. E.; Gaisne,
   G.; Morales, N.; Murgas, F.; Pepe, F.; Rodriguez, E.; Santos, N. C.;
   Tal-Or, L.; Tsapras, Y.; Udry, S.
Bibcode: 2022yCat..36640064G
Altcode:
  This work makes use of data from HARPS, the University College London
  Echelle Spectrograph (UCLES) , and the Planet Finding Spectrograph
  (PFS). HARPS data are available as raw images and reduced spectra,
  while we accessed UCLES and PFS data only as RV time series. We used
  a total of 227 RV data points for GJ 832. <P />(3 data files).

Title: The CARMENES search for exoplanets around M dwarfs. Rotational
    variation in activity indicators of Ross 318, YZ CMi, TYC 3529-1437-1,
    and EV Lac
Authors: Schöfer, P.; Jeffers, S. V.; Reiners, A.; Zechmeister,
   M.; Fuhrmeister, B.; Lafarga, M.; Ribas, I.; Quirrenbach, A.; Amado,
   P. J.; Caballero, J. A.; Anglada-Escudé, G.; Bauer, F. F.; Béjar,
   V. J. S.; Cortés-Contreras, M.; Alonso, E. Díez; Dreizler, S.;
   Guenther, E. W.; Herbort, O.; Johnson, E. N.; Kaminski, A.; Kürster,
   M.; Montes, D.; Morales, J. C.; Pedraz, S.; Tal-Or, L.
Bibcode: 2022A&A...663A..68S
Altcode: 2022arXiv220411685S
  Context. The Calar Alto high-Resolution search for M dwarfs with
  Exo-earths with Near-infrared and optical Échelle Spectrographs
  (CARMENES) instrument is searching for periodic radial-velocity (RV)
  variations of M dwarfs, which are induced by orbiting planets. However,
  there are other potential sources of such variations, including
  rotational modulation caused by stellar activity. <BR /> Aims: We
  aim to investigate four M dwarfs (Ross 318, YZ CMi, TYC 3529-1437-1,
  and EV Lac) with different activity levels and spectral sub-types. Our
  goal is to compare the periodicities seen in 22 activity indicators
  and the stellar RVs, and to examine their stability over time. <BR
  /> Methods: For each star, we calculated generalised Lomb-Scargle
  periodograms of pseudo-equivalent widths of chromospheric lines,
  indices of photospheric bands, the differential line width as a measure
  of the width of the average photospheric absorption line, the RV, the
  chromatic index that describes the wavelength dependence of the RV,
  and parameters of the cross-correlation function. We also calculated
  periodograms for subsets of the data and compared our results to TESS
  photometry. <BR /> Results: We find the rotation periods of all four
  stars to manifest themselves in the RV and photospheric indicators,
  particularly the TiO 7050 index, whereas the chromospheric lines
  show clear signals only at lower activity levels. For EV Lac and
  TYC 3529-1437-1, we find episodes during which indicators vary with
  the rotation period, and episodes during which they vary with half
  the rotation period, similarly to photometric light curves. <BR />
  Conclusions: The changing periodicities reflect the evolution of stellar
  activity features on the stellar surface. We therefore conclude that
  our results not only emphasise the importance of carefully analysing
  indicators complementary to the RV in RV surveys, but they also suggest
  that it is also useful to search for signals in activity indicators
  in subsets of the dataset, because an activity signal that is present
  in the RV may not be visible in the activity indicators all the time,
  in particular for the most active stars.

Title: Transit Timing Variations for AU Microscopii b and c
Authors: Wittrock, Justin M.; Dreizler, Stefan; Reefe, Michael A.;
   Morris, Brett M.; Plavchan, Peter P.; Lowrance, Patrick J.; Demory,
   Brice-Olivier; Ingalls, James G.; Gilbert, Emily A.; Barclay, Thomas;
   Cale, Bryson L.; Collins, Karen A.; Collins, Kevin I.; Crossfield,
   Ian J. M.; Dragomir, Diana; Eastman, Jason D.; Mufti, Mohammed El;
   Feliz, Dax; Gagné, Jonathan; Gaidos, Eric; Gao, Peter; Geneser,
   Claire S.; Hebb, Leslie; Henze, Christopher E.; Horne, Keith D.;
   Jenkins, Jon M.; Jensen, Eric L. N.; Kane, Stephen R.; Kaye, Laurel;
   Martioli, Eder; Monsue, Teresa A.; Pallé, Enric; Quintana, Elisa
   V.; Radford, Don J.; Roccatagliata, Veronica; Schlieder, Joshua E.;
   Schwarz, Richard P.; Shporer, Avi; Stassun, Keivan G.; Stockdale,
   Christopher; Tan, Thiam-Guan; Tanner, Angelle M.; Vanderburg, Andrew;
   Vega, Laura D.; Wang, Songhu
Bibcode: 2022AJ....164...27W
Altcode: 2022arXiv220205813W
  We explore the transit timing variations (TTVs) of the young (22 Myr)
  nearby AU Mic planetary system. For AU Mic b, we introduce three Spitzer
  (4.5 μm) transits, five TESS transits, 11 LCO transits, one PEST
  transit, one Brierfield transit, and two transit timing measurements
  from Rossiter-McLaughlin observations; for AU Mic c, we introduce
  three TESS transits. We present two independent TTV analyses. First, we
  use EXOFASTv2 to jointly model the Spitzer and ground-based transits
  and obtain the midpoint transit times. We then construct an O -
  C diagram and model the TTVs with Exo-Striker. Second, we reproduce
  our results with an independent photodynamical analysis. We recover a
  TTV mass for AU Mic c of ${10.8}_{-2.2}^{+2.3}$ M <SUB>⊕</SUB>. We
  compare the TTV-derived constraints to a recent radial velocity
  (RV) mass determination. We also observe excess TTVs that do not
  appear to be consistent with the dynamical interactions of b and
  c alone or due to spots or flares. Thus, we present a hypothetical
  nontransiting "middle-d" candidate exoplanet that is consistent with
  the observed TTVs and candidate RV signal and would establish the AU
  Mic system as a compact resonant multiplanet chain in a 4:6:9 period
  commensurability. These results demonstrate that the AU Mic planetary
  system is dynamically interacting, producing detectable TTVs, and the
  implied orbital dynamics may inform the formation mechanisms for this
  young system. We recommend future RV and TTV observations of AU Mic
  b and c to further constrain the masses and confirm the existence of
  possible additional planet(s).

Title: A detailed analysis of the Gl 486 planetary system
Authors: Caballero, J. A.; Gonzalez-Alvarez, E.; Brady, M.; Trifonov,
   T.; Ellis, T. G.; Dorn, C.; Cifuentes, C.; Molaverdikhani, K.; Bean,
   J. L.; Boyajian, T.; Rodriguez, E.; Sanz-Forcada, J.; Zapatero Osorio,
   M. R.; Abia, C.; Amado, P. J.; Anugu, N.; Bejar, V. J. S.; Davies,
   C. L.; Dreizler, S.; Dubois, F.; Ennis, J.; Espinoza, N.; Farrington,
   C. D.; Garcia Lopez, A.; Gardner, T.; Hatzes, A. P.; Henning, Th.;
   Herrero, E.; Herrero-Cisneros, E.; Kaminski, A.; Kasper, D.; Klement,
   R.; Kraus, S.; Labdon, A.; Lanthermann, C.; Le Bouquin, J. -B.; Lopez
   Gonzalez, M. J.; Luque, R.; Mann, A. W.; Marfil, E.; Monnier, J. D.;
   Montes, D.; Morales, J. C.; Palle, E.; Pedraz, S.; Quirrenbach, A.;
   Reffert, S.; Reiners, A.; Ribas, I.; Rodriguez-Lopez, C.; Schaefer, G.;
   Schweitzer, A.; Seifahrt, A.; Setterholm, B. R.; Shan, Y.; Shulyak,
   D.; Solano, E.; Sreenivas, K. R.; Stefansson, G.; Stuermer, J.;
   Tabernero, H. M.; Tal-Or, L.; ten Brummelaar, T.; Vanaverbeke, S.;
   von Braun, K.; Youngblood, A.; Zechmeister, M.
Bibcode: 2022arXiv220609990C
Altcode:
  The Gl 486 system consists of a very nearby, relatively bright, weakly
  active M3.5 V star at just 8 pc with a warm transiting rocky planet of
  about 1.3 R_Terra and 3.0 M_Terra that is ideal for both transmission
  and emission spectroscopy and for testing interior models of telluric
  planets. To prepare for future studies, we collected light curves of
  seven new transits observed with the CHEOPS space mission and new radial
  velocities obtained with MAROON-X/Gemini North and CARMENES/Calar
  Alto telescopes, together with previously published spectroscopic
  and photometric data from the two spectrographs and TESS. We also
  performed interferometric observations with the CHARA Array and
  new photometric monitoring with a suite of smaller telescopes. From
  interferometry, we measure a limb-darkened disc angular size of the
  star Gl 486. Together with a corrected Gaia EDR3 parallax, we obtain
  a stellar radius. We also measure a stellar rotation period at P_rot ~
  49.9 d, an upper limit to its XUV (5-920 AA) flux with new Hubble/STIS
  data, and, for the first time, a variety of element abundances (Fe,
  Mg, Si, V, Sr, Zr, Rb) and C/O ratio. Besides, we impose restrictive
  constraints on the presence of additional components, either stellar or
  substellar, in the system. With the input stellar parameters and the
  radial-velocity and transit data, we determine the radius and mass of
  the planet Gl 486 b at R_p = 1.343+/0.063 R_Terra and M_p = 3.00+/-0.13
  M_Terra. From the planet parameters and the stellar element abundances,
  we infer the most probable models of planet internal structure and
  composition, which are consistent with a relatively small metallic
  core with respect to the Earth, a deep silicate mantle, and a thin
  volatile upper layer. With all these ingredients, we outline prospects
  for Gl 486 b atmospheric studies, especially with forthcoming James
  Webb Space Telescope observations (abridged).

Title: Transit Timing Variations for AU Microscopii b &amp; c
Authors: Wittrock, Justin M.; Dreizler, Stefan; Reefe, Michael; Morris,
   Brett; Plavchan, Peter; Lowrance, Patrick; Demory, Brice-Olivier;
   Ingalls, James; Gilbert, Emily; Barclay, Thomas; Cale, Bryson; Collins,
   Karen; Collins, Kevin; Crossfield, Ian; Dragomir, Diana; Eastman,
   Jason; El Mufti, Mohammed; Feliz, Dax; Gagné, Jonathan; Gaidos, Eric;
   Gao, Peter; Geneser, Claire; Hebb, Leslie; Henze, Chris; Horne, Keith;
   Jenkins, Jon; Jensen, Eric; Kane, Stephen; Kaye, Laurel; Martioli,
   Eder; Monsue, Teresa; Palle Bago, Enric; Quintana, Elisa; Radford,
   Don; Roccatagliata, Veronica; Schlieder, Joshua; Schwarz, Richard;
   Shporer, Avi; Stassun, Keivan; Stockdale, Christopher; Tan, Thiam-Guan;
   Tanner, Angelle; Vanderburg, Andrew; Vega, Laura; Wang, Songhu
Bibcode: 2022BAAS...54e.275W
Altcode:
  We explore the transit timing variations (TTVs) of the young (22 Myr)
  nearby AU Mic planetary system. For AU Mic b, we introduce three
  Spitzer (4.5 μm) transits, five TESS transits, 11 LCO transits,
  one PEST transit, one Brierfield transit, and two transit timing
  measurements from Rossiter-McLaughlin observations; for AU Mic c,
  we introduce three TESS transits. We present two independent TTV
  analyses. First, we use EXOFASTv2 to jointly model the Spitzer and
  ground-based transits and to obtain the midpoint transit times. We then
  construct an O-C diagram and model the TTVs with Exo-Striker. Second,
  we reproduce our results with an independent photodynamical analysis. We
  recover a TTV mass for AU Mic c of 10.8+2.3-2.2 M<SUB>⊕</SUB>. We
  compare the TTV-derived constraints to a recent radial-velocity (RV)
  mass determination. We also observe excess TTVs that do not appear to
  be consistent with the dynamical interactions of b and c alone, and do
  not appear to be due to spots or flares. Thus, we present a hypothetical
  non-transiting "middle-d" candidate exoplanet that is consistent with
  the observed TTVs, the candidate RV signal, and would establish the AU
  Mic system as a compact resonant multi-planet chain in a 4:6:9 period
  commensurability. These results demonstrate that the AU Mic planetary
  system is dynamically interacting producing detectable TTVs, and the
  implied orbital dynamics may inform the formation mechanisms for this
  young system. We recommend future RV and TTV observations of AU Mic
  b and c to further constrain the masses and to confirm the existence
  of possible additional planet(s).

Title: VizieR Online Data Catalog: Thorium in solar twins (Botelho+,
    2019)
Authors: Botelho, R. B.; Milone, A. De C.; Melendez, J.; Bedell, M.;
   Spina, L.; Asplund, M.; Dos Santos, L.; Bean, J. L.; Ramirez, I.;
   Yong, D.; Dreizler, S.; Alves-Brito, A.; Yana Galarza, J.
Bibcode: 2022yCat..74821690B
Altcode:
  The sample is composed of 67 solar twins (stars with effective
  temperature, surface gravity, and metallicity around the solar values
  within {+/-}100K in Teff and within {+/-}0.1dex in logg and [Fe/H]),
  which were recently analysed by Spina et al. (2018MNRAS.474.2580S) and
  Bedell et al. (2018ApJ...865...68B). Spina et al. (2018MNRAS.474.2580S)
  derived their photospheric parameters by applying a line-by-line
  differential spectroscopic analysis relative to the Sun through
  equivalent width (EW) measurements of FeI and FeII lines. The estimated
  typical errors in Teff, logg, [Fe/H], and {xi} (micro-turbulence
  velocity) are, respectively, 4K, 0.012, 0.004dex and 0.011km/s. High
  Accuracy Radial velocity Planet Searcher (HARPS) spectra are used
  in this work to extract Th abundances. HARPS is an ultra-stable
  echelle spectrograph installed on the 3.6m telescope of the European
  Southern Observatory (ESO) at La Silla Observatory in Chile (Mayor
  et al. 2003Msngr.114...20M). The HARPS spectra covers λ=3780-6910Å
  under a resolving power R=115000. Each one-dimensional spectrum comes
  from more than 50 stacked spectra that are previously Doppler-corrected
  and carefully continuum normalized. <P />(3 data files).

Title: VizieR Online Data Catalog: VRI photometry and radial velocity
    of TOI-1759 (Espinoza+, 2022)
Authors: Espinoza, N.; Palle, E.; Kemmer, J.; Luque, R.; Caballero,
   J. A.; Cifuentes, C.; Herrero, E.; Sanchez Bejar, V. J.; Stock, S.;
   Molaverdikhani, K.; Morello, G.; Kossakowski, D.; Schlecker, M.; Amado,
   P. J.; Bluhm, P.; Cortes-Contreras, M.; Henning, T.; Kreidberg, L.;
   Kurster, M.; Lafarga, M.; Lodieu, N.; Morales, J. C.; Oshagh, M.;
   Passegger, V. M.; Pavlov, A.; Quirrenbach, A.; Reffert, S.; Reiners,
   A.; Ribas, I.; Rodriguez, E.; Lopez, C. R.; Schweitzer, A.; Trifonov,
   T.; Chaturvedi, P.; Dreizler, S.; Jeffers, S. V.; Kaminski, A.;
   Lopez-Gonzalez, M. J.; Lillo-Box, J.; Montes, D.; Nowak, G.; Pedraz,
   S.; Vanaverbeke, S.; Zapatero Osorio, M. R.; Zechmeister, M.; Collins,
   K. A.; Girardin, E.; Guerra, P.; Naves, R.; Crossfield, I. J. M.;
   Matthews, E. C.; Howell, S. B.; Ciardi, D. R.; Gonzales, E.; Matson,
   R. A.; Beichman, C. A.; Schlieder, J. E.; Barclay, T.; Vezie, M.;
   Villasenor, J. N.; Daylan, T.; Mireies, I.; Dragomir, D.; Twicken,
   J. D.; Jenkins, J.; Winn, J. N.; Latham, D.; Ricker, G.; Seager, S.
Bibcode: 2022yCat..51630133E
Altcode:
  The 2 minutes cadence data were processed in the TESS Science Processing
  Operations Center (SPOC) photometry and transit search pipelines at
  NASA Ames Research Center, in Sectors 16 (2019 September to October),
  17 (2019 October to November), and 24 (2020 April to May). <P />Among
  the observations, a transit of TOI-1759b in 2020 May 21 was captured by
  three independent telescopes/observatories: the OAA telescope of the
  Observatori Astronomic Albanya (Spain; precision of 1140ppm; R-filter
  observations), the RCO telescope of the Grand-Pra Observatory (Valais
  Sion, Switzerland; precision of 1080ppm; ip-filter observations),
  and the OMC telescope of the Montcabrer Observatory (Barcelona,
  Spain; precision of 1500ppm; Ic-filter observations). <P />Long-term
  photometric monitoring was also performed from the ground using the
  0.8m Joan Oro telescope (TJO) at the Montsec Observatory in Lleida,
  Spain and the 90cm telescope at the Sierra Nevada Observatory (SNO)
  in R and V filter. <P />We monitored TOI-1759 with the CARMENES 38
  instrument located on the 3.5m telescope at the Calar Alto Observatory
  in Almeria, Spain, from 2020 July 24 to 2021 January 17 (R=94600). <P
  />(3 data files).

Title: A black hole detected in the young massive LMC cluster NGC 1850
Authors: Saracino, S.; Kamann, S.; Guarcello, M. G.; Usher, C.;
   Bastian, N.; Cabrera-Ziri, I.; Gieles, M.; Dreizler, S.; Da Costa,
   G. S.; Husser, T. -O.; Hénault-Brunet, V.
Bibcode: 2022MNRAS.511.2914S
Altcode: 2021MNRAS.tmp.2924S; 2021arXiv211106506S
  We report on the detection of a black hole (NGC 1850 BH1) in the
  ~100-Myr-old massive cluster NGC 1850 in the Large Magellanic Cloud. It
  is in a binary system with a main-sequence turn-off star (4.9 ± 0.4
  M<SUB>⊙</SUB>), which is starting to fill its Roche lobe and is
  becoming distorted. Using 17 epochs of Very Large Telescope/Multi-Unit
  Spectroscopic Explorer observations, we detected radial velocity
  variations exceeding 300 km s<SUP>-1</SUP> associated with the target
  star, linked to the ellipsoidal variations measured by the fourth
  phase of the Optical Gravitational Lensing Experiment in the optical
  bands. Under the assumption of a semidetached system, the simultaneous
  modelling of radial velocity and light curves constrains the orbital
  inclination of the binary to 38° ± 2°, resulting in a true mass of
  the unseen companion of $11.1_{-2.4}^{+2.1}\,{\rm M}_{\odot }$. This
  represents the first direct dynamical detection of a black hole in
  a young massive cluster, opening up the possibility of studying the
  initial mass function and the early dynamical evolution of such compact
  objects in high-density environments.

Title: The MAVERIC Survey: The first radio and X-ray limits on the
    detached black holes in NGC 3201
Authors: Paduano, Alessandro; Bahramian, Arash; Miller-Jones,
   James C. A.; Kawka, Adela; Göttgens, Fabian; Strader, Jay; Chomiuk,
   Laura; Kamann, Sebastian; Dreizler, Stefan; Heinke, Craig O.; Husser,
   Tim-Oliver; Maccarone, Thomas J.; Tremou, Evangelia; Zhao, Yue
Bibcode: 2022MNRAS.510.3658P
Altcode: 2021MNRAS.tmp.3428P; 2022arXiv220101418P
  The Galactic globular cluster (GC) NGC 3201 is the first Galactic
  GC observed to host dynamically confirmed stellar-mass black holes
  (BHs), containing two confirmed and one candidate BH. This result
  indicates that GCs can retain BHs, which has important implications
  for GC evolution. NGC 3201 has been observed as part of the MAVERIC
  survey of Galactic GCs. We use these data to confirm that there is
  no radio or X-ray detection of the three BHs, and present the first
  radio and X-ray limits on these sources. These limits indicate that
  any accretion present is at an extremely low rate and may be extremely
  inefficient. In particular, for the system ACS ID #21859, by assuming
  the system is tidally locked and any accretion is through the capture
  of the companion's winds, we constrain the radiative efficiency of
  any accretion to ≲ 1.5 × 10<SUP>-5</SUP>. We also combine the
  radio and X-ray source catalogues from the MAVERIC survey with the
  existing MUSE spectroscopic surveys and the HUGS catalogue of NGC
  3201 to provide a catalogue of 42 multiwavelength sources in this
  cluster. We identify a new red straggler source with X-ray emission,
  and investigate the multiwavelength properties of the sub-subgiant
  population in the cluster.

Title: A Transiting, Temperate Mini-Neptune Orbiting the M Dwarf
    TOI-1759 Unveiled by TESS
Authors: Espinoza, Néstor; Pallé, Enric; Kemmer, Jonas; Luque,
   Rafael; Caballero, José A.; Cifuentes, Carlos; Herrero, Enrique;
   Sánchez Béjar, Víctor J.; Stock, Stephan; Molaverdikhani, Karan;
   Morello, Giuseppe; Kossakowski, Diana; Schlecker, Martin; Amado,
   Pedro J.; Bluhm, Paz; Cortés-Contreras, Miriam; Henning, Thomas;
   Kreidberg, Laura; Kürster, Martin; Lafarga, Marina; Lodieu, Nicolas;
   Morales, Juan Carlos; Oshagh, Mahmoudreza; Passegger, Vera M.; Pavlov,
   Alexey; Quirrenbach, Andreas; Reffert, Sabine; Reiners, Ansgar; Ribas,
   Ignasi; Rodríguez, Eloy; López, Cristina Rodríguez; Schweitzer,
   Andreas; Trifonov, Trifon; Chaturvedi, Priyanka; Dreizler, Stefan;
   Jeffers, Sandra V.; Kaminski, Adrian; López-González, María José;
   Lillo-Box, Jorge; Montes, David; Nowak, Grzegorz; Pedraz, Santos;
   Vanaverbeke, Siegfried; Zapatero Osorio, Maria R.; Zechmeister,
   Mathias; Collins, Karen A.; Girardin, Eric; Guerra, Pere; Naves,
   Ramon; Crossfield, Ian J. M.; Matthews, Elisabeth C.; Howell, Steve
   B.; Ciardi, David R.; Gonzales, Erica; Matson, Rachel A.; Beichman,
   Charles A.; Schlieder, Joshua E.; Barclay, Thomas; Vezie, Michael;
   Villaseñor, Jesus Noel; Daylan, Tansu; Mireies, Ismael; Dragomir,
   Diana; Twicken, Joseph D.; Jenkins, Jon; Winn, Joshua N.; Latham,
   David; Ricker, George; Seager, Sara
Bibcode: 2022AJ....163..133E
Altcode: 2022arXiv220201240E
  We report the discovery and characterization of TOI-1759 b, a temperate
  (400 K) sub-Neptune-sized exoplanet orbiting the M dwarf TOI-1759
  (TIC 408636441). TOI-1759 b was observed by TESS to transit in
  Sectors 16, 17, and 24, with only one transit observed per sector,
  creating an ambiguity regarding the orbital period of the planet
  candidate. Ground-based photometric observations, combined with
  radial-velocity measurements obtained with the CARMENES spectrograph,
  confirm an actual period of 18.85019 ± 0.00014 days. A joint
  analysis of all available photometry and radial velocities reveals a
  radius of 3.17 ± 0.10 R <SUB>⊕</SUB> and a mass of 10.8 ± 1.5 M
  <SUB>⊕</SUB>. Combining this with the stellar properties derived
  for TOI-1759 (R <SUB>⋆</SUB> = 0.597 ± 0.015 R <SUB>⊙</SUB>;
  M <SUB>⋆</SUB> = 0.606 ± 0.020 M <SUB>⊙</SUB>; T <SUB>eff</SUB>
  = 4065 ± 51 K), we compute a transmission spectroscopic metric
  (TSM) value of over 80 for the planet, making it a good target for
  transmission spectroscopy studies. TOI-1759 b is among the top five
  temperate, small exoplanets (T <SUB>eq</SUB> &lt; 500 K, R <SUB>
  p </SUB> &lt; 4 R <SUB>⊕</SUB>) with the highest TSM discovered to
  date. Two additional signals with periods of 80 days and &gt;200 days
  seem to be present in our radial velocities. While our data suggest
  both could arise from stellar activity, the later signal's source and
  periodicity are hard to pinpoint given the ~200 days baseline of our
  radial-velocity campaign with CARMENES. Longer baseline radial-velocity
  campaigns should be performed in order to unveil the true nature of
  this long-period signal.

Title: Discovery and mass measurement of the hot, transiting,
    Earth-sized planet, GJ 3929 b
Authors: Kemmer, J.; Dreizler, S.; Kossakowski, D.; Stock,
   S.; Quirrenbach, A.; Caballero, J. A.; Amado, P. J.; Collins,
   K. A.; Espinoza, N.; Herrero, E.; Jenkins, J. M.; Latham, D. W.;
   Lillo-Box, J.; Narita, N.; Pallé, E.; Reiners, A.; Ribas, I.;
   Ricker, G.; Rodríguez, E.; Seager, S.; Vanderspek, R.; Wells, R.;
   Winn, J.; Aceituno, F. J.; Béjar, V. J. S.; Barclay, T.; Bluhm, P.;
   Chaturvedi, P.; Cifuentes, C.; Collins, K. I.; Cortés-Contreras, M.;
   Demory, B. -O.; Fausnaugh, M. M.; Fukui, A.; Gómez Maqueo Chew, Y.;
   Galadí-Enríquez, D.; Gan, T.; Gillon, M.; Golovin, A.; Hatzes, A. P.;
   Henning, Th.; Huang, C.; Jeffers, S. V.; Kaminski, A.; Kunimoto,
   M.; Kürster, M.; López-González, M. J.; Lafarga, M.; Luque,
   R.; McCormac, J.; Molaverdikhani, K.; Montes, D.; Morales, J. C.;
   Passegger, V. M.; Reffert, S.; Sabin, L.; Schöfer, P.; Schanche, N.;
   Schlecker, M.; Schroffenegger, U.; Schwarz, R. P.; Schweitzer, A.;
   Sota, A.; Tenenbaum, P.; Trifonov, T.; Vanaverbeke, S.; Zechmeister, M.
Bibcode: 2022A&A...659A..17K
Altcode: 2022arXiv220200970K
  We report the discovery of GJ 3929 b, a hot Earth-sized planet orbiting
  the nearby M3.5 V dwarf star, GJ 3929 (G 180-18, TOI-2013). Joint
  modelling of photometric observations from TESS sectors 24 and 25
  together with 73 spectroscopic observations from CARMENES and follow-up
  transit observations from SAINT-EX, LCOGT, and OSN yields a planet
  radius of R<SUB>b</SUB> = 1.150 ± 0.040 R<SUB>⊕</SUB>, a mass of
  M<SUB>b</SUB> = 1.21 ± 0.42 M<SUB>⊕</SUB>, and an orbital period
  of P<SUB>b</SUB> = 2.6162745 ± 0.0000030 d. The resulting density
  of ρ<SUB>b</SUB> = 4.4 ± 1.6 g cm<SUP>−3</SUP> is compatible with
  the Earth's mean density of about 5.5 g cm<SUP>−3</SUP>. Due to the
  apparent brightness of the host star (J = 8.7 mag) and its small size,
  GJ 3929 b is a promising target for atmospheric characterisation with
  the JWST. Additionally, the radial velocity data show evidence for
  another planet candidate with P<SUB>[c]</SUB> = 14.303 ± 0.035 d, which
  is likely unrelated to the stellar rotation period, P<SUB>rot</SUB>
  = 122 ± 13 d, which we determined from archival HATNet and ASAS-SN
  photometry combined with newly obtained TJO data. <P />RV data and
  stellar activity indices are only available at the CDS via anonymous ftp
  to <A href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/659/A17">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/659/A17</A>

Title: VizieR Online Data Catalog: GJ 3929 b RVs and activity
    indicators (Kemmer+, 2022)
Authors: Kemmer, J.; Dreizler, S.; Kossakowski, D.; Stock, S.;
   Quirrenbach, A.; Caballero, J. A.; Amado, P. J.; Collins, K. A.;
   Espinoza, N.; Herrero, E.; Jenkins, J. M.; Latham, D. W.; Lillo-Box,
   J.; Narita, N.; Palle, E.; Reiners, A.; Ribas, I.; Ricker, G.;
   Rodriguez, E.; Seager, S.; Vanderspek, R.; Wells, R.; Winn, J.;
   Aceituno, F. J.; Bejar, V. J. S.; Barclay, T.; Bluhm, P.; Chaturvedi,
   P.; Cifuentes, C.; Collins, K. I.; Cortes-Contreras, M.; Demory, B. O.;
   Fausnaugh, M. M.; Fukui, A.; Gomez Maqueo Chew, Y.; Galadi-Enriquez,
   D.; Gan, T.; Gillon, M.; Golovin, A.; Hatzes, A. P.; Henning, T.;
   Huang, C.; Jeffers, S. V.; Kaminski, A.; Kunimoto, M.; Kurster,
   M.; Lopez-Gonzalez, M. J.; Lafarga, M.; Luque, R.; McCormac, J.;
   Molaverdikhani, K.; Montes, D.; Morales, J. C.; Passegger, V. M.;
   Reffert, S.; Sabin, L.; Schoefer, P.; Schanche, N.; Schlecker,
   M.; Schroffenegger, U.; Schwarz, R. P.; Schweitzer, A.; Sota, A.;
   Tenenbaum, P.; Trifonov, T.; Vanaverbeke, S.; Zechmeister, M.
Bibcode: 2022yCat..36590017K
Altcode:
  Radial velocities and activity indices of GJ 3929 acquired with CARMENES
  (Quirrenbach et al., 2014, in Proc. SPIE, Vol. 9147, Ground-based and
  Airborne Instrumentation for Astronomy V, 91471F), a high-resolution
  precise echelle spectrograph mounted at the 3.5m telescope at the
  Calar Alto Observatory in Spain. <P />(1 data file).

Title: A multi-planetary system orbiting the early-M dwarf TOI-1238
Authors: González-Álvarez, E.; Zapatero Osorio, M. R.; Sanz-Forcada,
   J.; Caballero, J. A.; Reffert, S.; Béjar, V. J. S.; Hatzes, A. P.;
   Herrero, E.; Jeffers, S. V.; Kemmer, J.; López-González, M. J.;
   Luque, R.; Molaverdikhani, K.; Morello, G.; Nagel, E.; Quirrenbach,
   A.; Rodríguez, E.; Rodríguez-López, C.; Schlecker, M.; Schweitzer,
   A.; Stock, S.; Passegger, V. M.; Trifonov, T.; Amado, P. J.; Baker,
   D.; Boyd, P. T.; Cadieux, C.; Charbonneau, D.; Collins, K. A.; Doyon,
   R.; Dreizler, S.; Espinoza, N.; Fűrész, G.; Furlan, E.; Hesse, K.;
   Howell, S. B.; Jenkins, J. M.; Kidwell, R. C.; Latham, D. W.; McLeod,
   K. K.; Montes, D.; Morales, J. C.; O'Dwyer, T.; Pallé, E.; Pedraz,
   S.; Reiners, A.; Ribas, I.; Quinn, S. N.; Schnaible, C.; Seager, S.;
   Skinner, B.; Smith, J. C.; Schwarz, R. P.; Shporer, A.; Vanderspek,
   R.; Winn, J. N.
Bibcode: 2022A&A...658A.138G
Altcode: 2021arXiv211114602G
  Context. The number of super-Earth and Earth-mass planet discoveries has
  increased significantly in the last two decades thanks to the Doppler
  radial velocity and planetary transit observing techniques. Either
  technique can detect planet candidates on its own, but the power
  of a combined photometric and spectroscopic analysis is unique for
  an insightful characterization of the planets, which in turn has
  repercussions for our understanding of the architecture of planetary
  systems and, therefore, their formation and evolution. <BR /> Aims: Two
  transiting planet candidates with super-Earth radii around the nearby
  (d = 70.64 ± 0.06 pc) K7-M0 dwarf star TOI-1238 were announced by
  NASA's Transiting Exoplanet Survey Satellite (TESS), which observed
  the field of TOI-1238 in four different sectors. We aim to validate
  their planetary nature using precise radial velocities taken with
  the CARMENES spectrograph. <BR /> Methods: We obtained 55 CARMENES
  radial velocity measurements that span the 11 months between 9 May
  2020 and 5 April 2021. For a better characterization of the parent
  star's activity, we also collected contemporaneous optical photometric
  observations at the Joan Oró and Sierra Nevada observatories and
  retrieved archival photometry from the literature. We performed a
  combined TESS+CARMENES photometric and spectroscopic analysis by
  including Gaussian processes and Keplerian orbits to account for the
  stellar activity and planetary signals simultaneously. <BR /> Results:
  We estimate that TOI-1238 has a rotation period of 40 ± 5 d based on
  photometric and spectroscopic data. The combined analysis confirms the
  discovery of two transiting planets, TOI-1238 b and c, with orbital
  periods of 0.764597<SUB>−0.000011</SUB><SUP>+0.000013</SUP>
  d and 3.294736<SUB>−0.000036</SUB><SUP>+0.000034</SUP> d,
  masses of 3.76<SUB>−1.07</SUB><SUP>+1.15</SUP> M<SUB>⊕</SUB>
  and 8.32<SUB>−1.88</SUB><SUP>+1.90</SUP> M<SUB>⊕</SUB>, and
  radii of 1.21<SUB>−0.10</SUB><SUP>+0.11</SUP> R<SUB>⊕</SUB> and
  2.11<SUB>−0.14</SUB><SUP>+0.14</SUP> R<SUB>⊕</SUB>. They orbit
  their parent star at semimajor axes of 0.0137 ± 0.0004 au and 0.036 ±
  0.001 au, respectively.The two planets are placed on opposite sides of
  the radius valley for M dwarfs and lie between the star and the inner
  border of TOI-1238's habitable zone. The inner super-Earth TOI-1238
  b is one of the densest ultra-short-period planets ever discovered
  (ρ = 11.7<SUB>−3.4</SUB><SUP>+4.2</SUP> g cm<SUP>−3</SUP>). The
  CARMENES data also reveal the presence of an outer, non-transiting,
  more massive companion with an orbital period and radial velocity
  amplitude of ≥600 d and ≥70 m s<SUP>−1</SUP>, which implies a
  likely mass of M ≥ 2 √(1− e<SUP>2</SUP>) M<SUB>Jup</SUB> and a
  separation ≥1.1 au from its parent star.

Title: MUSE crowded field 3D spectroscopy in NGC 300. II. Quantitative
    spectroscopy of BA-type supergiants
Authors: González-Torà, G.; Urbaneja, M. A.; Przybilla, N.; Dreizler,
   S.; Roth, M. M.; Kamann, S.; Castro, N.
Bibcode: 2022A&A...658A.117G
Altcode: 2022arXiv220101311G
  <BR /> Aims: A quantitative spectral analysis of BA-type supergiants
  and bright giants in an inner spiral arm region of the nearby spiral
  galaxy NGC 300 is presented, based on observations with the Multi Unit
  Spectroscopic Explorer (MUSE) on the European Southern Obsevatory, Very
  Large Telescope. The flux-weighted gravity-luminosity relationship
  (FGLR), a stellar spectroscopic distance determination method for
  galaxies, is extended towards stars at lower luminosities. <BR
  /> Methods: Point spread function fitting 3D spectroscopy was
  performed with PampelMUSE on the datacube. The 16 stars with the
  highest signal-to-noise ratios are classified with regard to their
  spectral type and luminosity class using Galactic templates. They
  were analysed using hybrid non-local thermodynamic equilibrium
  model spectra to fit the strongest observed hydrogen, helium, and
  metal lines in the intermediate-resolution spectra. Supplemented by
  photometric data, this facilitates fundamental stellar parameters
  and interstellar reddening which have yet to be determined. <BR />
  Results: Effective temperatures, surface gravities, reddening E(B−V),
  bolometric magnitudes and luminosities, as well as radii and masses
  are presented for the sample stars. The majority of the objects follow
  the FGLR as established from more luminous BA-type supergiants in NGC
  300. An increase in the scatter in the flux-weighted gravity-luminosity
  plane is observed at these lower luminosities, which is in line with
  predictions from population synthesis models.

Title: TOI-1201 b: A mini-Neptune transiting a bright and moderately
    young M dwarf
Authors: Kossakowski, D.; Kemmer, J.; Bluhm, P.; Stock, S.; Caballero,
   J. A.; Béjar, V. J. S.; Guillén, C. Cardona; Lodieu, N.; Collins,
   K. A.; Oshagh, M.; Schlecker, M.; Espinoza, N.; Pallé, E.; Henning,
   Th.; Kreidberg, L.; Kürster, M.; Amado, P. J.; Anderson, D. R.;
   Morales, J. C.; Cartwright, S.; Charbonneau, D.; Chaturvedi, P.;
   Cifuentes, C.; Conti, D. M.; Cortés-Contreras, M.; Dreizler, S.;
   Galadí-Enríquez, D.; Guerra, P.; Hart, R.; Hellier, C.; Henze,
   C.; Herrero, E.; Jeffers, S. V.; Jenkins, J. M.; Jensen, E. L. N.;
   Kaminski, A.; Kielkopf, J. F.; Kunimoto, M.; Lafarga, M.; Latham,
   D. W.; Lillo-Box, J.; Luque, R.; Molaverdikhani, K.; Montes, D.;
   Morello, G.; Morgan, E. H.; Nowak, G.; Pavlov, A.; Perger, M.;
   Quintana, E. V.; Quirrenbach, A.; Reffert, S.; Reiners, A.; Ricker,
   G.; Ribas, I.; López, C. Rodríguez; Osorio, M. R. Zapatero; Seager,
   S.; Schöfer, P.; Schweitzer, A.; Trifonov, T.; Vanaverbeke, S.;
   Vanderspek, R.; West, R.; Winn, J.; Zechmeister, M.
Bibcode: 2021A&A...656A.124K
Altcode: 2021arXiv210909346K
  We present the discovery of a transiting mini-Neptune around TOI-1201,
  a relatively bright and moderately young early M dwarf (J ≈ 9.5
  mag, ~600-800 Myr) in an equal-mass ~8 arcsecond-wide binary system,
  using data from the Transiting Exoplanet Survey Satellite, along with
  follow-up transit observations. With an orbital period of 2.49 d,
  TOI-1201 b is a warm mini-Neptune with a radius of R<SUB>b</SUB> =
  2.415 ± 0.090 R<SUB>⊕</SUB>. This signal is also present in the
  precise radial velocity measurements from CARMENES, confirming the
  existence of the planet and providing a planetary mass of M<SUB>b</SUB>
  = 6.28 ± 0.88 M<SUB>⊕</SUB> and, thus, an estimated bulk density
  of 2.45<SUB>−0.42</SUB><SUP>+0.48</SUP> g cm<SUP>−3</SUP>. The
  spectroscopic observations additionally show evidence of a signal
  with a period of 19 d and a long periodic variation of undetermined
  origin. In combination with ground-based photometric monitoring
  from WASP-South and ASAS-SN, we attribute the 19 d signal to the
  stellar rotation period (P<SUB>rot</SUB> = 19-23 d), although we
  cannot rule out that the variation seen in photometry belongs to
  the visually close binary companion. We calculate precise stellar
  parameters for both TOI-1201 and its companion. The transiting
  planet is anexcellent target for atmosphere characterization (the
  transmission spectroscopy metric is 97<SUB>−16</SUB><SUP>+21</SUP>)
  with the upcoming James Webb Space Telescope. It is also feasible to
  measure its spin-orbit alignment via the Rossiter-McLaughlin effect
  using current state-of-the-art spectrographs with submeter per second
  radial velocity precision. <P />Additional data (i.e., stellar activity
  indicators) are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/656/A124">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/656/A124</A>

Title: The CARMENES search for exoplanets around M dwarfs. Stellar
    atmospheric parameters of target stars with SteParSyn
Authors: Marfil, E.; Tabernero, H. M.; Montes, D.; Caballero, J. A.;
   Lázaro, F. J.; González Hernández, J. I.; Nagel, E.; Passegger,
   V. M.; Schweitzer, A.; Ribas, I.; Reiners, A.; Quirrenbach, A.;
   Amado, P. J.; Cifuentes, C.; Cortés-Contreras, M.; Dreizler, S.;
   Duque-Arribas, C.; Galadí-Enríquez, D.; Henning, Th.; Jeffers,
   S. V.; Kaminski, A.; Kürster, M.; Lafarga, M.; López-Gallifa, Á.;
   Morales, J. C.; Shan, Y.; Zechmeister, M.
Bibcode: 2021A&A...656A.162M
Altcode: 2021arXiv211007329M
  We determined effective temperatures, surface gravities, and
  metallicities for a sample of 343 M dwarfs observed with CARMENES,
  the double-channel, high-resolution spectrograph installed at the
  3.5 m telescope at Calar Alto Observatory. We employed SteParSyn,
  a Bayesian spectral synthesis implementation particularly designed to
  infer the stellar atmospheric parameters of late-type stars following
  a Markov chain Monte Carlo approach. We made use of the BT-Settl model
  atmospheres and the radiative transfer code turbospectrum to compute a
  grid of synthetic spectra around 75 magnetically insensitive Fe I and Ti
  I lines plus the TiO γ and ϵ bands. To avoid any potential degeneracy
  in the parameter space, we imposed Bayesian priors on T<SUB>eff</SUB>
  and logg based on the comprehensive, multi-band photometric data
  available for the sample. We find that this methodology is suitable down
  to M7.0 V, where refractory metals such as Ti are expected to condense
  in the stellar photospheres. The derived T<SUB>eff</SUB>, logg, and
  [Fe/H] range from 3000 to 4200 K, 4.5 to 5.3 dex, and −0.7 to 0.2
  dex, respectively. Although our T<SUB>eff</SUB> scale is in good
  agreement with the literature, we report large discrepancies in the
  [Fe/H] scales, which might arise from the different methodologies and
  sets of lines considered. However, our [Fe/H] is in agreement with the
  metallicity distribution of FGK-type stars in the solar neighbourhood
  and correlates well with the kinematic membership of the targets in the
  Galactic populations. Lastly, excellent agreement in T<SUB>eff</SUB> is
  found for M dwarfs with interferometric angular diameter measurements,
  as well as in the [Fe/H] between the components in the wide physical
  FGK+M and M+M systems included in our sample. <P />Full Tables
  B.1-B.3 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/656/A162">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/656/A162</A>

Title: Diving Beneath the Sea of Stellar Activity: Chromatic Radial
    Velocities of the Young AU Mic Planetary System
Authors: Cale, Bryson L.; Reefe, Michael; Plavchan, Peter; Tanner,
   Angelle; Gaidos, Eric; Gagné, Jonathan; Gao, Peter; Kane, Stephen
   R.; Béjar, Víctor J. S.; Lodieu, Nicolas; Anglada-Escudé, Guillem;
   Ribas, Ignasi; Pallé, Enric; Quirrenbach, Andreas; Amado, Pedro J.;
   Reiners, Ansgar; Caballero, José A.; Rosa Zapatero Osorio, María;
   Dreizler, Stefan; Howard, Andrew W.; Fulton, Benjamin J.; Xuesong
   Wang, Sharon; Collins, Kevin I.; El Mufti, Mohammed; Wittrock, Justin;
   Gilbert, Emily A.; Barclay, Thomas; Klein, Baptiste; Martioli, Eder;
   Wittenmyer, Robert; Wright, Duncan; Addison, Brett; Hirano, Teruyuki;
   Tamura, Motohide; Kotani, Takayuki; Narita, Norio; Vermilion, David;
   Lee, Rena A.; Geneser, Claire; Teske, Johanna; Quinn, Samuel N.;
   Latham, David W.; Esquerdo, Gilbert A.; Calkins, Michael L.; Berlind,
   Perry; Zohrabi, Farzaneh; Stibbards, Caitlin; Kotnana, Srihan; Jenkins,
   Jon; Twicken, Joseph D.; Henze, Christopher; Kidwell, Richard; Burke,
   Christopher; Villaseñor, Joel; Boyd, Patricia
Bibcode: 2021AJ....162..295C
Altcode: 2021arXiv210913996C
  We present updated radial-velocity (RV) analyses of the AU
  Mic system. AU Mic is a young (22 Myr) early-M dwarf known
  to host two transiting planets-P <SUB> b </SUB> ~ 8.46 days,
  ${R}_{b}={4.38}_{-0.18}^{+0.18}\ {R}_{\oplus }$ , P <SUB> c </SUB>
  ~ 18.86 days, ${R}_{c}={3.51}_{-0.16}^{+0.16}\ {R}_{\oplus }$ . With
  visible RVs from Calar Alto high-Resolution search for M dwarfs with
  Exo-earths with Near-infrared and optical echelle Spectrographs
  (CARMENES)-VIS, CHIRON, HARPS, HIRES, MINERVA-Australis, and
  Tillinghast Reflector Echelle Spectrograph, as well as near-infrared
  (NIR) RVs from CARMENES-NIR, CSHELL, IRD, iSHELL, NIRSPEC, and SPIRou,
  we provide a 5σ upper limit to the mass of AU Mic c of M <SUB> c </SUB>
  ≤ 20.13 M <SUB>⊕</SUB> and present a refined mass of AU Mic b of
  ${M}_{b}={20.12}_{-1.57}^{+1.72}\ {M}_{\oplus }$ . Used in our analyses
  is a new RV modeling toolkit to exploit the wavelength dependence of
  stellar activity present in our RVs via wavelength-dependent Gaussian
  processes. By obtaining near-simultaneous visible and near-infrared
  RVs, we also compute the temporal evolution of RV "color" and
  introduce a regressional method to aid in isolating Keplerian from
  stellar activity signals when modeling RVs in future works. Using a
  multiwavelength Gaussian process model, we demonstrate the ability
  to recover injected planets at 5σ significance with semi-amplitudes
  down to ≍10 m s<SUP>-1</SUP> with a known ephemeris, more than an
  order of magnitude below the stellar activity amplitude. However,
  we find that the accuracy of the recovered semi-amplitudes is ~50%
  for such signals with our model.

Title: Central kinematics of the Galactic globular cluster M80
Authors: Göttgens, Fabian; Kamann, Sebastian; Baumgardt, Holger;
   Dreizler, Stefan; Giesers, Benjamin; Husser, Tim-Oliver; den Brok,
   Mark; Fétick, Romain; Krajnovic, Davor; Weilbacher, Peter M.
Bibcode: 2021MNRAS.507.4788G
Altcode: 2021arXiv210811393G; 2021MNRAS.tmp.2212G
  We use spectra observed with the integral-field spectrograph Multi
  Unit Spectroscopic Explorer (MUSE) to reveal the central kinematics
  of the Galactic globular cluster Messier 80 (M80, NGC 6093). Using
  observations obtained with the recently commissioned narrow-field mode
  of MUSE, we are able to analyse 932 stars in the central 7.5 arcsec
  by 7.5 arcsec of the cluster for which no useful spectra previously
  existed. Mean radial velocities of individual stars derived from the
  spectra are compared to predictions from axisymmetric Jeans models,
  resulting in radial profiles of the velocity dispersion, the rotation
  amplitude, and the mass-to-light ratio. The new data allow us to
  search for an intermediate-mass black hole (IMBH) in the centre of
  the cluster. Our Jeans model finds two similarly probable solutions
  around different dynamical cluster centres. The first solution has a
  centre close to the photometric estimates available in the literature
  and does not need an IMBH to fit the observed kinematics. The second
  solution contains a location of the cluster centre that is offset
  by about 2.4 arcsec from the first one and it needs an IMBH mass
  of $4600^{+1700}_{-1400}~\text{M}_\odot {}$. N-body models support
  the existence of an IMBH in this cluster with a mass of up to 6000
  M<SUB>⊙</SUB> in this cluster, although models without an IMBH
  provide a better fit to the observed surface brightness profile. They
  further indicate that the cluster has lost nearly all stellar-mass black
  holes. We further discuss the detection of two potential high-velocity
  stars with radial velocities of 80-90 $\text{km}\, \text{s}^{-1}$
  relative to the cluster mean.

Title: VizieR Online Data Catalog: CARMENES stellar atmospheric
    parameters (Marfil+, 2021)
Authors: Marfil, E.; Tabernero, H. M.; Montes, D.; Caballero, J. A.;
   Lazaro, F. J.; Gonzalez Hernandez, J. I.; Nagel, E.; Passegger, V. M.;
   Schweitzer, A.; Ribas, I.; Reiners, A.; Quirrenbach, A.; Amado, P. J.;
   Cifuentes, C.; Cortes-Contreras, M.; Dreizler, S.; Duque-Arribas,
   C.; Galadi-Enriquez, D.; Henning, T.; Jeffers, S. V.; Kaminski, A.;
   Kurster, M.; Lafarga, M.; Lopez-Gallifa, A.; Morales, J. C.; Shan,
   Y.; Zechmeister, M.
Bibcode: 2021yCat..36560162M
Altcode:
  We present basic information of investigated M dwarfs, atomic data of
  the selected TiI and FeI lines, wavelength ranges synthesised, and
  the stellar atmospheric parameters (effective temperatures, surface
  gravities, and metallicities) derived for the sample with SteParSyn. <P
  />(3 data files).

Title: Mapping magnetic activity indicators across the M dwarf domain
Authors: Lafarga, Marina; Ribas, Ignasi; Reiners, Ansgar; Quirrenbach,
   Andreas; Amado, Pedro J.; Caballero, Jose A.; Azzaro, Marco;
   Béjar, Víctor J. S.; Cortés-Contreras, Miriam; Dreizler, Stefan;
   Hatzes, Artie P.; Henning, Thomas; Jeffers, Sandra V.; Kaminski,
   A.; Kürster, Martin; Montes, David; Morales, Juan Carlos; Oshagh,
   Mahmoud; Rodríguez-López, Cristina; Schöfer, Patrick; Schweitzer,
   Andreas; Zechmeister, Mathias
Bibcode: 2021spc..confE...7L
Altcode:
  Stellar activity poses one of the main obstacles for the detection and
  characterisation of exoplanets around cool stars, as it can induce
  radial velocity (RV) signals that can hide or mimic the presence of
  companions. Several activity indicators are routinely used to identify
  activity-related signals in RV measurements, but not all indicators
  trace exactly the same effects, nor are any of them always effective
  in all stars. In this work, we evaluate the performance of a set of
  common spectroscopic activity indicators for 98 M dwarfs observed
  with CARMENES. We find that different indicators behave differently
  depending on the mass and activity level of the target star. In
  addition, we also observe that stars at the low-mass end of the
  sample show the lowest RV scatter, which could potentially hint at
  different manifestations of activity compared to higher-mass stars,
  as well as being better candidates for planet searches. Overall, our
  results show that when assessing the origin of an RV signal, it is
  critical to take into account a large set of indicators, or at least
  the most effective ones considering the characteristics of the star,
  as failing to do so may lead to false planet claims.

Title: The CARMENES search for exoplanets around M dwarfs. Not-so-fine
    hyperfine-split vanadium lines in cool star spectra
Authors: Shan, Y.; Reiners, A.; Fabbian, D.; Marfil, E.; Montes,
   D.; Tabernero, H. M.; Ribas, I.; Caballero, J. A.; Quirrenbach, A.;
   Amado, P. J.; Aceituno, J.; Béjar, V. J. S.; Cortés-Contreras, M.;
   Dreizler, S.; Hatzes, A. P.; Henning, Th.; Jeffers, S. V.; Kaminski,
   A.; Kürster, M.; Lafarga, M.; Morales, J. C.; Nagel, E.; Pallé, E.;
   Passegger, V. M.; Rodriguez-López, C.; Schweitzer, A.; Zechmeister, M.
Bibcode: 2021A&A...654A.118S
Altcode: 2021arXiv210812442S
  Context. M-dwarf spectra are complex and notoriously difficult to model,
  posing challenges to understanding their photospheric properties and
  compositions in depth. Vanadium (V) is an iron-group element whose
  abundance supposedly closely tracks that of iron, but has origins that
  are not completely understood. <BR /> Aims: Our aim is to characterize
  a series of neutral vanadium atomic absorption lines in the 800-910
  nm wavelength region of high signal-to-noise, high-resolution,
  telluric-corrected M-dwarf spectra from the CARMENES survey. Many
  of these lines are prominent and exhibit a distinctive broad and
  flat-bottom shape, which is a result of hyperfine structure (HFS). We
  investigate the potential and implications of these HFS split lines
  for abundance analysis of cool stars. <BR /> Methods: With standard
  spectral synthesis routines, as provided by the spectroscopy software
  iSpec and the latest atomic data (including HFS) available from the
  VALD3 database, we modeled these striking line profiles. We used them
  to measure V abundances of cool dwarfs. <BR /> Results: We determined
  V abundances for 135 early M dwarfs (M0.0 V to M3.5 V) in the CARMENES
  guaranteed time observations sample. They exhibit a [V/Fe]-[Fe/H]
  trend consistent with that derived from nearby FG dwarfs. The tight
  (±0.1 dex) correlation between [V/H] and [Fe/H] suggests the potential
  application of V as an alternative metallicity indicator in M dwarfs. We
  also show hints that neglecting to model HFS could partially explain
  the temperature correlation in V abundance measurements observed in
  previous studies of samples involving dwarf stars with T<SUB>eff</SUB>
  ≲ 5300 K. <BR /> Conclusions: Our work suggests that HFS can impact
  certain absorption lines in cool photospheres more severely than in
  Sun-like ones. Therefore, we advocate that HFS should be carefully
  treated in abundance studies in stars cooler than ~5000 K. On the other
  hand, strong HFS split lines in high-resolution spectra present an
  opportunity for precision chemical analyses of large samples of cool
  stars. The V-to-Fe trends exhibited by the local M dwarfs continue
  to challenge theoretical models of V production in the Galaxy. <P
  />Full Table A.1 is only available at the CDS via anonymous ftp to
  <A href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/654/A118">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/654/A118</A>

Title: VizieR Online Data Catalog: Metallicities on multiple MSs of
    Omega Centauri (Latour+, 2021)
Authors: Latour, M.; Calamida, A.; Husser, T. -O.; Kamann, S.;
   Dreizler, S.; Brinchmann, J.
Bibcode: 2021yCat..36539008L
Altcode:
  We analyzed the MUSE spectra of selected stars on the MS of Omega
  Centauri. We include the stars selected by us on the red- and blue-MS
  as well as additional stars included in the 15 MSs identified by
  Bellini et al., (2017, Cat. J/ApJ/844/164). We include only the stars
  that have a spectrum with S/N&gt;15. The effective temperatures and
  metallicities are derived from a full spectral fit against grids
  of model atmospheres computed with the PHEONIX code (Husser et al.,
  2011A&amp;A...533A...6B). We note that the model atmospheres used for
  the fits are alpha-enhanced ([alpha/Fe]=0.3). Uncertainties on Teff and
  M/H are calibrated as explained in the paper. Surface gravities are
  derived from isochrones. Uncertainties on the log g are the standard
  deviations of the log g values obtained from different isochrones
  (see text in the paper for more details). <P />IDs and coordinates are
  from Bellini (2017, Cat. J/ApJ/844/164) and the populations tags can
  be retrieved from Bellini et al. (2017, Cat. J/ApJ/844/164). <P />(1
  data file).

Title: VizieR Online Data Catalog: TOI-1201 RV and activity index
    (Kossakowski+, 2021)
Authors: Kossakowski, D.; Kemmer, J.; Bluhm, P.; Stock, S.; Caballero,
   J. A.; Bejar, V. J. S.; Cardona Guillen, C.; Lodieu, N.; Collins,
   K. A.; Oshagh, M.; Schlecker, M.; Espinoza, N.; Palle, E.; Henning,
   Th.; Kreidberg, L.; Kuerster, M.; Amado, P. J.; Anderson, D. R.;
   Morales, J. C.; Cartwright, S.; Charbonneau, D.; Chaturvedi, P.;
   Cifuentes, C.; Conti, D. M.; Cortes-Contreras, M.; Dreizler, S.;
   Galadi-Enriquez, D.; Guerra, P.; Hart, R.; Hellier, C.; Henze,
   C.; Herrero, E.; Jeffers, S. V.; Jenkins, J. M.; Jensen, E. L. N.;
   Kaminski, A.; Kielkopf, J. F.; Kunimoto, M.; Lafarga, M.; Latham,
   D. W.; Lillo-Box, J.; Luque, R.; Molvaerdikhani, K.; Montes, D.;
   Morello, G.; Morgan, E. H.; Nowak, G.; Pavlov, A.; Perger, M.;
   Quintana, E. V.; Quirrenbach, A.; Reffert, S.; Reiners, A.; Ricker,
   G.; Ribas, I.; Rodriguez Lopez, C.; Zapatero Osorio, M. R.; Seager,
   S.; Schoefer, P.; Schweitzer, A.; Trifonov, T.; Vanaverbeke, S.;
   Vanderspek, R.; West, R.; Winn, J.; Zechmeister, M.
Bibcode: 2021yCat..36560124K
Altcode:
  High-resolution spectroscopy taken with the CARMENES VIS instrument
  for the two M dwarfs in a binary system, TOI-1201 and its companion
  (PM J02489-1432E). Likewise, the stellar activity indicators are output
  from the SERVAL pipeline (Zechmeister et al. 2018A&amp;A...609A..12Z),
  namely, this entails the chromatic index (CRX), the differential line
  width (dLW), the Halpha index, the Calcium triplet lines (CAIRT). The
  photospheric TiO absorption band indices (at 7050Å, 8430Å, and 8860Å)
  following Schoefer et al. (2019A&amp;A...623A..44S, Cat. J/A+A/623/A44)
  are included. Also, the cross-correlation function parameters,
  as provided following Lafarga et al. (2020A&amp;A...636A..36L,
  Cat. J/A+A/636/A36), are included and these are: bisector velocity span
  (BVS), contrast (CTR), and full width at half maximum (FWHM). <P />Most
  observations are simultaneously, however there are 33 data points for
  TOI-1201 (Nov. 2019 - Feb. 2020) and 23 for PM J02489-1432E (Nov. 2019 -
  Jan. 2020). <P />(2 data files).

Title: The CARMENES search for exoplanets around M
    dwarfs. Spectroscopic orbits of nine M-dwarf multiple systems,
    including two triples, two brown dwarf candidates, and one close
    M-dwarf-white dwarf binary
Authors: Baroch, D.; Morales, J. C.; Ribas, I.; Béjar, V. J. S.;
   Reffert, S.; Cardona Guillén, C.; Reiners, A.; Caballero, J. A.;
   Quirrenbach, A.; Amado, P. J.; Anglada-Escudé, G.; Colomé, J.;
   Cortés-Contreras, M.; Dreizler, S.; Galadí-Enríquez, D.; Hatzes,
   A. P.; Jeffers, S. V.; Henning, Th.; Herrero, E.; Kaminski, A.;
   Kürster, M.; Lafarga, M.; Lodieu, N.; López-González, M. J.;
   Montes, D.; Pallé, E.; Perger, M.; Pollacco, D.; Rodríguez-López,
   C.; Rodríguez, E.; Rosich, A.; Schöfer, P.; Schweitzer, A.; Shan,
   Y.; Tal-Or, L.; Zechmeister, M.
Bibcode: 2021A&A...653A..49B
Altcode: 2021arXiv210514770B
  Context. M dwarfs are ideal targets for the search of Earth-size
  planets in the habitable zone using the radial velocity method,
  and are attracting the attention of many ongoing surveys. One of the
  expected results of these surveys is that new multiple-star systems
  have also been found. This is the case also for the CARMENES survey,
  thanks to which nine new double-line spectroscopic binary systems have
  already been announced. <BR /> Aims: Throughout the five years of
  the survey the accumulation of new observations has resulted in the
  detection of several new multiple-stellar systems with long periods
  and low radial-velocity amplitudes. Here we newly characterise the
  spectroscopic orbits and constrain the masses of eight systems and
  update the properties of a system that we had reported earlier. <BR
  /> Methods: We derived the radial velocities of the stars using
  two-dimensional cross-correlation techniques and template matching. The
  measurements were modelled to determine the orbital parameters of the
  systems. We combined CARMENES spectroscopic observations with archival
  high-resolution spectra from other instruments to increase the time
  span of the observations and improve our analysis. When available,
  we also added archival photometric, astrometric, and adaptive optics
  imaging data to constrain the rotation periods and absolute masses
  of the components. <BR /> Results: We determined the spectroscopic
  orbits of nine multiple systems, eight of which are presented for
  the first time. The sample is composed of five single-line binaries,
  two double-line binaries, and two triple-line spectroscopic triple
  systems. The companions of two of the single-line binaries, GJ 3626 and
  GJ 912, have minimum masses below the stellar boundary, and thus could
  be brown dwarfs. We found a new white dwarf in a close binary orbit
  around the M star GJ 207.1, located at a distance of 15.79 pc. From a
  global fit to radial velocities and astrometric measurements, we were
  able to determine the absolute masses of the components of GJ 282 C,
  which is one of the youngest systems with measured dynamical masses.

Title: A stellar census in globular clusters with MUSE. A new
    perspective on the multiple main sequences of ω Centauri
Authors: Latour, M.; Calamida, A.; Husser, T. -O.; Kamann, S.;
   Dreizler, S.; Brinchmann, J.
Bibcode: 2021A&A...653L...8L
Altcode: 2021arXiv210901540L
  Context. ω Cen is a rare example of a globular cluster where the iron
  abundance of the stars spans more than one order of magnitude. Many
  spectroscopic investigations of its red-giant and sub-giant branches
  have revealed multiple peaks in the iron abundance distribution. The
  metallicity distribution of main sequence (MS) stars is not well
  characterized yet due to the faintness of the stars and lack of
  data. So far, almost all studies of MS stars have been based on
  photometric measurements. <BR /> Aims: Our goal is to investigate
  the metallicity distribution of a statistically significant sample of
  MS stars in ω Cen. In particular, we aim to revisit the metallicity
  difference between the red and blue MS of the cluster. <BR /> Methods:
  We used MUSE spectra obtained for the central region of ω Cen to
  derive metallicities for ≈4200 MS stars. <BR /> Results: We find
  that blue MS stars are, on average, ≈0.1 dex more metal-rich than
  their red counterparts. On the basis of this new estimate, we find
  that the two sequences can be fit on the Hubble Space Telescope
  color-magnitude diagram with two isochrones having the same global
  metallicity and age, but a higher helium abundance for the blue MS,
  that is ΔY ≲ 0.1. Furthermore, we determined the average metallicity
  of the five main populations along ω Cen MS and these estimates are
  consistent with expectations from previous photometric studies. <P
  />Table B.1 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/653/L8">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/653/L8</A>
  <P />Based on observations collected at the European Organisation
  for Astronomical Research in the Southern Hemisphere, Chile (Program
  IDs 094.D-0142(B), 095.D-0629(A), 096.D-0175(A), 097.D-0295(A),
  098.D-0148(A), 099.D-0019(A), 0100.D-0161(A), 0101.D-0268(A),
  0102.D-0270(A), 0103.D-0204(A), and 0104.D-0257(B)).

Title: The CARMENES search for exoplanets around M dwarfs. Planet
    occurrence rates from a subsample of 71 stars
Authors: Sabotta, S.; Schlecker, M.; Chaturvedi, P.; Guenther,
   E. W.; Muñoz Rodríguez, I.; Muñoz Sánchez, J. C.; Caballero,
   J. A.; Shan, Y.; Reffert, S.; Ribas, I.; Reiners, A.; Hatzes, A. P.;
   Amado, P. J.; Klahr, H.; Morales, J. C.; Quirrenbach, A.; Henning,
   Th.; Dreizler, S.; Pallé, E.; Perger, M.; Azzaro, M.; Jeffers, S. V.;
   Kaminski, A.; Kürster, M.; Lafarga, M.; Montes, D.; Passegger, V. M.;
   Zechmeister, M.
Bibcode: 2021A&A...653A.114S
Altcode: 2021arXiv210703802S
  Context. The CARMENES exoplanet survey of M dwarfs has obtained more
  than 18 000 spectra of 329 nearby M dwarfs over the past five years as
  part of its guaranteed time observations (GTO) program. <BR /> Aims:
  We determine planet occurrence rates with the 71 stars from the GTO
  program for which we have more than 50 observations. <BR /> Methods:
  We use injection-and-retrieval experiments on the radial-velocity
  time series to measure detection probabilities. We include 27
  planets in 21 planetary systems in our analysis. <BR /> Results:
  We find 0.06<SUB>−0.03</SUB><SUP>+0.04</SUP> giant planets (100
  M<SUB>⊕</SUB> &lt; M<SUB>pl</SUB> sin i &lt; 1000 M<SUB>⊕</SUB>)
  per star in periods of up to 1000 d, but due to a selection bias this
  number could be up to a factor of five lower in the whole 329-star
  sample. The upper limit for hot Jupiters (orbital period of less than
  10 d) is 0.03 planets per star, while the occurrence rate of planets
  with intermediate masses (10 M<SUB>⊕</SUB> &lt; M<SUB>pl</SUB> sin
  i &lt; 100 M<SUB>⊕</SUB>) is 0.18<SUB>−0.05</SUB><SUP>+0.07</SUP>
  planets per star. Less massive planets with 1 M<SUB>⊕</SUB> &lt;
  M<SUB>pl</SUB> sin i &lt; 10 M<SUB>⊕</SUB> are very abundant,
  with an estimated rate of 1.32<SUB>−0.31</SUB><SUP>+0.33</SUP>
  planets per star for periods of up to 100 d. When considering only
  late M dwarfs with masses M<SUB>⋆</SUB> &lt; 0.34 M<SUB>⊙</SUB>,
  planets more massive than 10 M<SUB>⊕</SUB> become rare. Instead,
  low-mass planets with periods shorter than 10 d are significantly
  overabundant. <BR /> Conclusions: For orbital periods shorter than
  100 d, our results confirm the known stellar mass dependences from
  the Kepler survey: M dwarfs host fewer giant planets and at least two
  times more planets with M<SUB>pl</SUB> sin i &lt; 10 M<SUB>⊕</SUB>
  than G-type stars. In contrast to previous results, planets around
  our sample of very low-mass stars have a higher occurrence rate in
  short-period orbits of less than 10 d. Our results demonstrate the
  need to take into account host star masses in planet formation models.

Title: VizieR Online Data Catalog: Vanadium measurements for 135 M
    dwarfs (Shan+, 2021)
Authors: Shan, Y.; Reiners, A.; Fabbian, D.; Marfil, E.; Montes,
   D.; Tabernero, H. M.; Ribas, I.; Caballero, J. A.; Quirrenbach, A.;
   Amado, P. J.; Aceituno, J.; Bejar, V. J. S.; Cortes-Contreras, M.;
   Dreizler, S.; Hatzes, A. P.; Henning, T.; Jeffers, S. V.; Kaminski,
   A.; Kuerster, M.; Lafarga, M.; Morales, J. C.; Nagel, E.; Palle, E.;
   Passegger, V. M.; Rodriguez-Lopez, C.; Schweitzer, A.; Zechmeister, M.
Bibcode: 2021yCat..36540118S
Altcode:
  Table A1 presents the measured V abundances ([V/H]) for 135
  nearby early-M dwarfs from the CARMENES GTO sample. Two sets
  of measurements are given, which are based on two independently
  measured sets of fundamental stellar parameters for this sample
  (Schweitzer et al., 2019A&amp;A...625A..68S, Cat. J/A+A/625/A68 and
  Marfil et al., submitted). Rotational velocities from Reiners et
  al. (2018A&amp;A...612A..49R, Cat. J/A+A/612/A49) and disk kinematic
  membership designations (Cortes-Contreras+ in prep) are also
  included. <P />(1 data file).

Title: The CARMENES search for exoplanets around M dwarfs. Mapping
    stellar activity indicators across the M dwarf domain
Authors: Lafarga, M.; Ribas, I.; Reiners, A.; Quirrenbach, A.;
   Amado, P. J.; Caballero, J. A.; Azzaro, M.; Béjar, V. J. S.;
   Cortés-Contreras, M.; Dreizler, S.; Hatzes, A. P.; Henning, Th.;
   Jeffers, S. V.; Kaminski, A.; Kürster, M.; Montes, D.; Morales,
   J. C.; Oshagh, M.; Rodríguez-López, C.; Schöfer, P.; Schweitzer,
   A.; Zechmeister, M.
Bibcode: 2021A&A...652A..28L
Altcode: 2021arXiv210513467L
  Context. Stellar activity poses one of the main obstacles for the
  detection and characterisation of small exoplanets around cool stars,
  as it can induce radial velocity (RV) signals that can hide or mimic
  the presence of planetary companions. Several indicators of stellar
  activity are routinely used to identify activity-related signals in
  RVs, but not all indicators trace exactly the same activity effects,
  nor are any of them always effective in all stars. <BR /> Aims:
  We evaluate the performance of a set of spectroscopic activity
  indicators for M dwarf stars with different masses and activity
  levels with the aim of finding a relation between the indicators
  and stellar properties. <BR /> Methods: In a sample of 98 M dwarfs
  observed with CARMENES, we analyse the temporal behaviour of RVs and
  nine spectroscopic activity indicators: cross-correlation function
  (CCF) full-width-at-half-maximum (FWHM), CCF contrast, CCF bisector
  inverse slope (BIS), RV chromatic index (CRX), differential line width
  (dLW), and indices of the chromospheric lines Hα and calcium infrared
  triplet. <BR /> Results: A total of 56 stars of the initial sample
  show periodic signals related to activity in at least one of these
  ten parameters. RV is the parameter for which most of the targets
  show an activity-related signal. CRX and BIS are effective activity
  tracers for the most active stars in the sample, especially stars with
  a relatively high mass, while for less active stars, chromospheric
  lines perform best. FWHM and dLW show a similar behaviour in all mass
  and activity regimes, with the highest number of activity detections
  in the low-mass, high-activity regime. Most of the targets for which
  we cannot identify any activity-related signals are stars at the
  low-mass end of the sample (i.e. with the latest spectral types). These
  low-mass stars also show the lowest RV scatter, which indicates that
  ultracool M dwarfs could be better candidates for planet searches
  than earlier types, which show larger RV jitter. <BR /> Conclusions:
  Our results show that the spectroscopic activity indicators analysed
  behave differently, depending on the mass and activity level of the
  target star. This underlines the importance of considering different
  indicators of stellar activity when studying the variability of RV
  measurements. Therefore, when assessing the origin of an RV signal,
  it is critical to take into account a large set of indicators, or at
  least the most effective ones considering the characteristics of the
  star, as failing to do so may lead to false planet claims. <P />Full
  Table A.1 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/652/A28">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/652/A28</A>

Title: Transit Timing Variations for AU Microscopii b &amp; c
Authors: Wittrock, Justin M.; Dreizler, Stefan; Reefe, Michael;
   Plavchan, Peter; Gilbert, Emily A.; Barclay, Thomas; Morris, Brett
   M.; Demory, Brice-Olivier; Dragomir, Diana; Crossfield, Ian J. M.;
   Ingalls, James; Lowrance, Patrick; Gao, Peter; Kaye, Laurel; Wang,
   Songhu; Newton, Elisabeth R.; Gaidos, Eric; Cale, Bryson L.; El Mufti,
   Mohammed; Collins, Kevin I.; Kane, Stephen R.; Tanner, Angelle; Gagné,
   Jonathan; Quintana, Elisa V.; Vega, Laura D.; Schlieder, Joshua E.;
   Monsue, Teresa; Hebb, Leslie; Stassun, Keivan G.; Roccatagliata,
   Veronica; Schwarz, Richard P.; Tan, T. G.; Radford, Don J.; Stockdale,
   Christopher
Bibcode: 2021tsc2.confE...7W
Altcode:
  AU Mic is a relatively bright, nearby (9.7 pc), young (22 Myr) M1V
  pre-main sequence star hosting two transiting exoplanets AU Mic b and c
  and a spatially-resolved outer dusty debris disk. This research explores
  the transit timing variations (TTVs) of AU Mic b and c. For AU Mic b,
  we present three Spitzer/IRAC (4.5 μm) transits (two new), five TESS
  Cycle 1 and 3 transits, 11 LCO transits, one PEST-0.30m transit,
  one Brierfield-0.36m transit, and two transit timing measurements
  from Rossiter-McLaughlin observations; for AU Mic c, we present three
  TESS Cycle 1 and 3 transits. We use EXOFASTv2 to jointly model the
  transits and to obtain the midpoint transit times. We then construct
  an O-C diagram to map the TTVs. We model the TTVs for AU Mic b and c
  with Exo-Striker to recover constraints on the mass for AU Mic c. We
  compare the TTV-derived constraints to a recent radial-velocity mass
  determination. The results demonstrate that the AU Mic planetary
  system is dynamically interacting producing detectable TTVs, and the
  implied orbital dynamics may inform future constraints on the formation
  mechanisms for this young planetary system. However, stellar activity
  from flares and rotational spot modulation complicate our analysis
  of this young system. We recommend future TTV observations of AU Mic
  b and c to further constrain the dynamical masses and to search for
  additional planets in the system.

Title: Small and rocky worlds orbiting M dwarfs: GJ 3473 b and GJ
    3929 b
Authors: Kemmer, Jonas; Stock, Stephan; Kossakowski, Diana; Dreizler,
   Stefan; Kaminski, Adrian; Molaverdikhani, Karan; Schlecker, Martin;
   Caballero, Jose A.
Bibcode: 2021tsc2.confE..67K
Altcode:
  We present two small transiting planets with mass measurements orbiting
  bright mid M dwarfs (GJ 3473, GJ 3929). GJ 3473 b (Kemmer et al. 2020)
  is a hot, presumably rocky, planet (P = 1.198 d, M<SUB>b</SUB> = 1.86
  ± 0.30 M<SUB>e</SUB>, and radius, R<SUB>b</SUB> = 1.264 ± 0.050
  R<SUB>e</SUB>), which is due to its high temperature a particularly
  attractive target for thermal emission spectroscopy. Further, it is
  accompanied by another non-transiting planet (Pc = 15.509 ± 0.033
  d) that has a minimum mass of M<SUB>c</SUB> sin i = 7.41 ± 0.91
  M<SUB>e</SUB>. For GJ 3929 b (in prep.) we present a preliminary
  analysis that yields a period of P = 2.616 d, mass M<SUB>b</SUB> =
  2.03 ± 0.59 M<SUB>e</SUB>, and radius, R<SUB>b</SUB> = 1.155 ± 0.043
  R<SUB>e</SUB>. The radial velocity data show evidence for another
  signal, whose origin is, however, not yet clarified. Both systems
  add to the TESS level-one science goal to measure the masses for 50
  transiting planets with radii smaller than 4 R<SUB>e</SUB>.

Title: Simultaneous photometric and CARMENES spectroscopic monitoring
    of fast-rotating M dwarf GJ 3270. Discovery of a post-flare corotating
    feature
Authors: Johnson, E. N.; Czesla, S.; Fuhrmeister, B.; Schöfer, P.;
   Shan, Y.; Cardona Guillén, C.; Reiners, A.; Jeffers, S. V.; Lalitha,
   S.; Luque, R.; Rodríguez, E.; Béjar, V. J. S.; Caballero, J. A.;
   Tal-Or, L.; Zechmeister, M.; Ribas, I.; Amado, P. J.; Quirrenbach,
   A.; Cortés-Contreras, M.; Dreizler, S.; Fukui, A.; López-González,
   M. J.; Hatzes, A. P.; Henning, Th.; Kaminski, A.; Kürster, M.;
   Lafarga, M.; Montes, D.; Morales, J. C.; Murgas, F.; Narita, N.;
   Pallé, E.; Parviainen, H.; Pedraz, S.; Pollacco, D.; Sota, A.
Bibcode: 2021A&A...651A.105J
Altcode: 2021arXiv210407080J
  Context. Active M dwarfs frequently exhibit large flares, which can
  pose an existential threat to the habitability of any planet in orbit
  in addition to making said planets more difficult to detect. M dwarfs
  do not lose angular momentum as easily as earlier-type stars, which
  maintain the high levels of stellar activity for far longer. Studying
  young, fast-rotating M dwarfs is key to understanding their near
  stellar environment and the evolution of activity. <BR /> Aims: We
  study stellar activity on the fast-rotating M dwarf GJ 3270. <BR />
  Methods: We analyzed dedicated high cadence, simultaneous, photometric
  and high-resolution spectroscopic observations obtained with CARMENES of
  GJ 3270 over 7.7 h, covering a total of eight flares of which two are
  strong enough to facilitate a detailed analysis. We consult the TESS
  data, obtained in the month prior to our own observations, to study
  rotational modulation and to compare the TESS flares to those observed
  in our campaign. <BR /> Results: The TESS data exhibit rotational
  modulation with a period of 0.37 d. The strongest flare covered
  by our observing campaign released a total energy of about 3.6 ×
  10<SUP>32</SUP> erg, putting it close to the superflare regime. This
  flare is visible in the B,V, r, i, and z photometric bands, which
  allows us to determine a peak temperature of about 10 000 K. The flare
  also leaves clear marks in the spectral time series. In particular,
  we observe an evolving, mainly blue asymmetry in chromospheric lines,
  which we attribute to a post-flare, corotating feature. To our knowledge
  this is the first time such a feature has been seen on a star other
  than our Sun. <BR /> Conclusions: Our photometric and spectroscopic
  time series covers the eruption of a strong flare followed up by a
  corotating feature analogous to a post-flare arcadal loop on the Sun
  with a possible failed ejection of material.

Title: VizieR Online Data Catalog: Activity indicators across the
    M dwarf domain (Lafarga+, 2021)
Authors: Lafarga, M.; Ribas, I.; Reiners, A.; Quirrenbach, A.; Amado,
   P. J.; Caballero, J. A.; Azzaro, M.; Bejar, V. J. S.; Cortes-Contreras,
   M.; Dreizler, S.; Hatzes, A. P.; Henning, T.; Jeffers, S. V.;
   Kaminski, A.; Kuerster, M.; Montes, D.; Morales, J. C.; Oshagh, M.;
   Rodriguez-Lopez, C.; Schoefer, P.; Schweitzer, A.; Zechmeister, M.
Bibcode: 2021yCat..36520028L
Altcode:
  Properties of the 98 sample stars. Values taken from the latest
  version of the Carmencita database available at the time. We also
  show the number of CARMENES VIS observations (before performing any
  sigma-clipping or discarding any observations due to low S/N), the
  number of different nights covered by the observations, their time span,
  and their RV scatter, measured as the standard deviation (std) of the
  corrected serval RVs (instrumental drift and nightly average corrected,
  averaged same-night observations, and linear trend removed). <P />(1
  data file).

Title: An ultra-short-period transiting super-Earth orbiting the M3
    dwarf TOI-1685
Authors: Bluhm, P.; Pallé, E.; Molaverdikhani, K.; Kemmer, J.; Hatzes,
   A. P.; Kossakowski, D.; Stock, S.; Caballero, J. A.; Lillo-Box, J.;
   Béjar, V. J. S.; Soto, M. G.; Amado, P. J.; Brown, P.; Cadieux, C.;
   Cloutier, R.; Collins, K. A.; Collins, K. I.; Cortés-Contreras, M.;
   Doyon, R.; Dreizler, S.; Espinoza, N.; Fukui, A.; González-Álvarez,
   E.; Henning, Th.; Horne, K.; Jeffers, S. V.; Jenkins, J. M.; Jensen,
   E. L. N.; Kaminski, A.; Kielkopf, J. F.; Kusakabe, N.; Kürster, M.;
   Lafrenière, D.; Luque, R.; Murgas, F.; Montes, D.; Morales, J. C.;
   Narita, N.; Passegger, V. M.; Quirrenbach, A.; Schöfer, P.; Reffert,
   S.; Reiners, A.; Ribas, I.; Ricker, G. R.; Seager, S.; Schweitzer,
   A.; Schwarz, R. P.; Tamura, M.; Trifonov, T.; Vanderspek, R.; Winn,
   J.; Zechmeister, M.; Zapatero Osorio, M. R.
Bibcode: 2021A&A...650A..78B
Altcode: 2021arXiv210301016B
  Dynamical histories of planetary systems, as well as the atmospheric
  evolution of highly irradiated planets, can be studied by characterizing
  the ultra-short-period planet population, which the TESS mission is
  particularly well suited to discover. Here, we report on the follow-up
  of a transit signal detected in the TESS sector 19 photometric time
  series of the M3.0 V star TOI-1685 (2MASS J04342248+4302148). We confirm
  the planetary nature of the transit signal, which has a period of
  P<SUB>b</SUB> = 0.6691403<SUB>−0.0000021</SUB><SUP>+0.0000023</SUP>
  d, using precise radial velocity measurements taken with the CARMENES
  spectrograph. From the joint photometry and radial velocity analysis,
  we estimate the following parameters for TOI-1685 b: a mass of
  M<SUB>b</SUB> = 3.78<SUB>−0.63</SUB><SUP>+0.63</SUP> M<SUB>⊕</SUB>,
  a radius of R<SUB>b</SUB> = 1.70<SUB>−0.07</SUB><SUP>+0.07</SUP>
  R<SUB>⊕</SUB>, which together result in a bulk density
  of ρ<SUB>b</SUB> = 4.21<SUB>−0.82</SUB><SUP>+0.95</SUP> g
  cm<SUP>−3</SUP>, and an equilibrium temperature of T<SUB>eq</SUB>
  = 1069<SUB>−16</SUB><SUP>+16</SUP> K. TOI-1685 b is the least dense
  ultra-short-period planet around an M dwarf known to date. TOI-1685 b
  is also one of the hottest transiting super-Earth planets with accurate
  dynamical mass measurements, which makes it a particularly attractive
  target for thermal emission spectroscopy. Additionally, we report with
  moderate evidence an additional non-transiting planet candidate in the
  system, TOI-1685 [c], which has an orbital period of P<SUB>c</SUB> =
  9.02<SUB>−0.12</SUB><SUP>+0.10</SUP> d.

Title: Deciphering the Formation History of Omega Cen with a
    Comprehensive Stellar Kinematic and Population Dataset
Authors: Seth, Anil C.; Alfaro Cuello, Mayte; Bellini, Andrea; Dotter,
   Aaron L.; Dreizler, S.; Haeberle, Maximilian; Hannah, Christian;
   Husser, Tim-Oliver; Kacharov, Nikolay; Kamann, Sebastian; Milone,
   Antonino Paolo; Neumayer, Nadine; Nitschai, Maria Selina; Pechetti,
   Renuka; Voggel, Karina; Weisz, Daniel R.; van de Ven, Glenn
Bibcode: 2021hst..prop16777S
Altcode:
  Omega Centauri appears to be the stripped nucleus of one of the
  largest satellite galaxies that has fallen into the Milky Way. Yet
  the formation history of Omega Centauri is poorly understood due
  to the complexity of its stellar populations. We propose to obtain
  WFC3/UVIS imaging to measure proper motions and use UV photometry to
  constrain stellar abundances and ages for hundreds of thousands of
  stars within Omega Centauri's effective radius. In combination with a
  MUSE spectral mosaic that will provide star-by-star metallicity and
  radial velocity measurements, we will create and publicly release
  an unprecedented catalog of 3-D stellar velocities, age estimates,
  and abundance information. This combination of kinematic and stellar
  population information will enable us to study the details of both how
  and when Omega Centauri formed. These results will provide insight on
  the galaxy in which Omega Centauri formed and its interaction with
  the Milky Way, and will serve as a template for understanding the
  formation and tidal stripping of nuclear star clusters.

Title: The CARMENES search for exoplanets around M dwarfs. Two
    terrestrial planets orbiting G 264-012 and one terrestrial planet
    orbiting Gl 393
Authors: Amado, P. J.; Bauer, F. F.; Rodríguez López, C.;
   Rodríguez, E.; Cardona Guillén, C.; Perger, M.; Caballero, J. A.;
   López-González, M. J.; Muñoz Rodríguez, I.; Pozuelos, F. J.;
   Sánchez-Rivero, A.; Schlecker, M.; Quirrenbach, A.; Ribas, I.;
   Reiners, A.; Almenara, J.; Astudillo-Defru, N.; Azzaro, M.; Béjar,
   V. J. S.; Bohemann, R.; Bonfils, X.; Bouchy, F.; Cifuentes, C.;
   Cortés-Contreras, M.; Delfosse, X.; Dreizler, S.; Forveille, T.;
   Hatzes, A. P.; Henning, Th.; Jeffers, S. V.; Kaminski, A.; Kürster,
   M.; Lafarga, M.; Lodieu, N.; Lovis, C.; Mayor, M.; Montes, D.;
   Morales, J. C.; Morales, N.; Murgas, F.; Ortiz, J. L.; Pallé, E.;
   Pepe, F.; Perdelwitz, V.; Pollaco, D.; Santos, N. C.; Schöfer, P.;
   Schweitzer, A.; Ségransan, N. C.; Shan, Y.; Stock, S.; Tal-Or, L.;
   Udry, S.; Zapatero Osorio, M. R.; Zechmeister, M.
Bibcode: 2021A&A...650A.188A
Altcode: 2021arXiv210513785A
  We report the discovery of two planetary systems, namely G 264-012,
  an M 4.0 dwarf with two terrestrial planets (M<SUB>b</SUB>
  sin i=2.50<SUB>−0.30</SUB><SUP>+0.29</SUP> M<SUB>⊕</SUB>
  and M<SUB>c</SUB> sin i=3.75<SUB>−0.47</SUB><SUP>+0.48</SUP>
  M<SUB>⊕</SUB>), and Gl 393, a bright M 2.0 dwarf with one terrestrial
  planet (M<SUB>b</SUB> sini = 1.71 ± 0.24M<SUB>⊕</SUB>). Although both
  stars were proposed to belong to young stellar kinematic groups, we
  estimate their ages to be older than about 700 Ma. The two planets
  around G 264-012 were discovered using only radial-velocity (RV)
  data from the CARMENES exoplanet survey, with estimated orbital
  periods of 2.30 d and 8.05 d, respectively.Photometric monitoring and
  analysis of activity indicators reveal a third signal present in the RV
  measurements, at about 100 d,caused by stellar rotation. The planet
  Gl 393 b was discovered in the RV data from the HARPS, CARMENES,
  and HIRES instruments. Its identification was only possible after
  modelling, with a Gaussian process (GP), the variability produced by
  the magnetic activity of the star. For the earliest observations,
  this variability produced a forest of peaks in the periodogram of
  the RVs at around the 34 d rotation period determined from Kepler
  data, which disappeared in the latestepochs. After correcting for
  them with this GP model, a significant signal showed at a period
  of 7.03 d. No significant signals in any of our spectral activity
  indicators or contemporaneous photometry were found at any of the
  planetary periods. Given the orbital and stellar properties, the
  equilibrium temperatures of the three planets are all higher than that
  for Earth. Current planet formation theories suggest that these two
  systems represent a common type of architecture. This is consistent
  with formation following the core accretion paradigm. <P />Full Tables
  B.1 and B.2 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/650/A188">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/650/A188</A>

Title: VizieR Online Data Catalog: G 264-012 and Gl 393 radial
    velocity curves (Amado+, 2021)
Authors: Amado, P. J.; Bauer, F. F.; Rodriguez Lopez, C.; Rodriguez,
   E.; Cardona Guillen, C.; Perger, M.; Caballero, J. A.; Lopez-Gonzalez,
   M. J.; Munoz-Rodriguez, I.; Pozuelos, F. J.; Sanchez-Rivero, A.;
   Schlecker, M.; Quirrenbach, A.; Ribas, I.; Reiners, A.; Almenara,
   J.; Astudillo-Defru, N.; Azzaro, M.; Bejar, V. J. S.; Bohemann, R.;
   Bonfils, X.; Bouchy, F.; Cifuentes, C.; Cortes-Contreras, M.; Delfosse,
   X.; Dreizler, S.; Forveille, T.; Hatzes, A. P.; Henning, T.; Jeffers,
   S. V.; Kaminski, A.; Kuerster, M.; Lafarga, M.; Lodieu, N.; Lovis, C.;
   Mayor, M.; Montes, D.; Morales, J. C.; Morales, N.; Murgas, F.; Ortiz,
   J. L.; Palle, E.; Pepe, F.; Perdelwitz, V.; Pollaco, D.; Santos, N. C.;
   Schoefer, P.; Schweitzer, A.; Segransan, N. C.; Shan, Y.; Stock, S.;
   Tal-Or, L.; Udry, S.; Zapatero Osorio, M. R.; Zechmeister, M.
Bibcode: 2021yCat..36500188A
Altcode:
  We tabulate the radial velocity (RV) time series (BJD) of the stars G
  264-012 and Gl 393, the error of each RV measurement and the instrument
  with which it was acquired. <P />(2 data files).

Title: VizieR Online Data Catalog: GJ 1151 radial velocity curve
    (Perger+, 2021)
Authors: Perger, M.; Ribas, I.; Anglada-Escude, G.; Morales, J. C.;
   Amado, P. J.; Caballero, J. A.; Quirrenbach, A.; Reiners, A.; Bejar,
   V. J. S.; Dreizler, S.; Galadi-Enriquez, D.; Hatzes, A. P.; Henning,
   T.; Jeffers, S. V.; Kaminski, A.; Kuerster, M.; Lafarga, M.; Montes,
   D.; Palle, E.; Rodriguez-Lopez, C.; Schweitzer, A.; Zapatero Osorio,
   M. R.; Zechmeister, M.
Bibcode: 2021yCat..36499012P
Altcode:
  CARMENES serval (CAR) and HARPS-N terra (HAN) radial velocities of GJ
  1151. <P />(1 data file).

Title: Mass and density of the transiting hot and rocky super-Earth
    LHS 1478 b (TOI-1640 b)
Authors: Soto, M. G.; Anglada-Escudé, G.; Dreizler, S.;
   Molaverdikhani, K.; Kemmer, J.; Rodríguez-López, C.; Lillo-Box, J.;
   Pallé, E.; Espinoza, N.; Caballero, J. A.; Quirrenbach, A.; Ribas, I.;
   Reiners, A.; Narita, N.; Hirano, T.; Amado, P. J.; Béjar, V. J. S.;
   Bluhm, P.; Burke, C. J.; Caldwell, D. A.; Charbonneau, D.; Cloutier,
   R.; Collins, K. A.; Cortés-Contreras, M.; Girardin, E.; Guerra, P.;
   Harakawa, H.; Hatzes, A. P.; Irwin, J.; Jenkins, J. M.; Jensen, E.;
   Kawauchi, K.; Kotani, T.; Kudo, T.; Kunimoto, M.; Kuzuhara, M.; Latham,
   D. W.; Montes, D.; Morales, J. C.; Mori, M.; Nelson, R. P.; Omiya, M.;
   Pedraz, S.; Passegger, V. M.; Rackham, B. V.; Rudat, A.; Schlieder,
   J. E.; Schöfer, P.; Schweitzer, A.; Selezneva, A.; Stockdale, C.;
   Tamura, M.; Trifonov, T.; Vanderspek, R.; Watanabe, D.
Bibcode: 2021A&A...649A.144S
Altcode: 2021arXiv210211640S
  One of the main objectives of the Transiting Exoplanet Survey
  Satellite (TESS) mission is the discovery of small rocky planets
  around relatively bright nearby stars. Here, we report the discovery
  and characterization of the transiting super-Earth planet orbiting
  LHS 1478 (TOI-1640). The star is an inactive red dwarf (J ~ 9.6 mag
  and spectral type m3 V) with mass and radius estimates of 0.20 ±
  0.01M<SUB>⊙</SUB> and 0.25 ± 0.01R<SUB>⊙</SUB>, respectively, and
  an effective temperature of 3381 ± 54 K. It was observed by TESS in
  four sectors. These data revealed a transit-like feature with a period
  of 1.949 days. We combined the TESS data with three ground-based transit
  measurements, 57 radial velocity (RV) measurements from CARMENES, and
  13 RV measurements from IRD, determining that the signal is produced
  by a planet with a mass of 2.33<SUB>−0.20</SUB><SUP>+0.20</SUP>
  M<SUB>⊕</SUB> and a radius of 1.24<SUB>−0.05</SUB><SUP>+0.05</SUP>
  R<SUB>⊕</SUB>. The resulting bulk density of this planet is 6.67 g
  cm<SUP>−3</SUP>, which is consistent with a rocky planet with an Fe-
  and MgSiO<SUB>3</SUB>-dominated composition. Although the planet would
  be too hot to sustain liquid water on its surface (its equilibrium
  temperature is about ~595 K, suggesting aVenus-like atmosphere),
  spectroscopic metrics based on the capabilities of the forthcoming
  James Webb Space Telescope and the fact that the host star is rather
  inactive indicate that this is one of the most favorable known rocky
  exoplanets for atmospheric characterization.

Title: The CARMENES search for exoplanets around M dwarfs. No evidence
    for a super-Earth in a 2-day orbit around GJ 1151
Authors: Perger, M.; Ribas, I.; Anglada-Escudé, G.; Morales, J. C.;
   Amado, P. J.; Caballero, J. A.; Quirrenbach, A.; Reiners, A.; Béjar,
   V. J. S.; Dreizler, S.; Galadí-Enríquez, D.; Hatzes, A. P.; Henning,
   Th.; Jeffers, S. V.; Kaminski, A.; Kürster, M.; Lafarga, M.; Montes,
   D.; Pallé, E.; Rodríguez-López, C.; Schweitzer, A.; Zapatero Osorio,
   M. R.; Zechmeister, M.
Bibcode: 2021A&A...649L..12P
Altcode: 2021arXiv210310216P
  Context. The interaction between Earth-like exoplanets and the magnetic
  field of low-mass host stars are considered to produce weak emission
  signals at radio frequencies. A study using LOFAR data announced the
  detection of radio emission from the mid M-type dwarf GJ 1151 that
  could potentially arise from a close-in terrestrial planet. Recently,
  the presence of a 2.5-M<SUB>⊕</SUB> planet orbiting GJ 1151 with a
  2-day period has been claimed using 69 radial velocities (RVs) from
  the HARPS-N and HPF instruments. <BR /> Aims: We have obtained 70 new
  high-precision RV measurements in the framework of the CARMENES M-dwarf
  survey and use these data to confirm the presence of the claimed planet
  and to place limits on possible planetary companions in the GJ 1151
  system. <BR /> Methods: We analysed the periodicities present in the
  combined RV data sets from all three instruments and calculated the
  detection limits for potential planets in short-period orbits. <BR
  /> Results: We cannot confirm the recently announced candidate
  planet and conclude that the 2-day signal in the HARPS-N and HPF
  data sets is most probably produced by a long-term RV variability,
  possibly arising from an outer planetary companion that has yet to
  be constrained. We calculate a 99.9% significance detection limit of
  1.50 m s<SUP>−1</SUP> in the RV semi-amplitude, which places upper
  limits of 0.7 M<SUB>⊕</SUB> and 1.2 M<SUB>⊕</SUB> on the minimum
  masses of potential exoplanets with orbital periods of 1 and 5 days,
  respectively. <P />Table A.1 is only available at the CDS via anonymous
  ftp to <A href="http://cdsarc.u-strasbg.fr/">cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/649/L12">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/649/L12</A>

Title: Stellar atmospheric parameters of CARMENES GTO M dwarfs with
    spectral synthesis and SteParSyn
Authors: Marfil, Emilio; Tabernero, Hugo M.; Montes, David; Caballero,
   Jose Antonio; Lazaro-Barrasa, Francisco Javier; González Hernández,
   Jonay I.; Nagel, Evangelos; Passegger, Vera M.; Schweitzer, Andreas;
   Ribas, Ignasi; Reiners, Ansgar; Quirrenbach, Andreas; Amado, Pedro
   J.; Cifuentes, Carlos; Cortés-Contreras, Miriam; Dreizler, Stefan;
   Duque-Arribas, Christian; Galadí-Enríquez, David; Henning, Thomas;
   Jeffers, Sandra V.; Kaminski, Adrian; Kürster, Martin; Lafarga,
   Marina; López-Gallifa, Álvaro; Morales, Juan Carlos; Shan, Yutong;
   Zechmeister, Matthias
Bibcode: 2021csss.confE..19M
Altcode: 2021csss.confE.298M
  We aim to review the spectral synthesis technique to derive the stellar
  atmospheric parameters (T<SUB>eff</SUB>, log g, and [Fe/H]) of 348 M
  dwarfs in light of the optical and near-infrared spectra obtained with
  CARMENES, the high-resolution, double-channel spectrograph installed at
  the 3.5 m telescope at the Calar Alto observatory (Spain). The analysis
  relies on the SteParSyn code as the preferred MCMC implementation of
  the spectral synthesis technique, along with 75 carefully selected,
  magnetically insensitive, Fe I and Ti I lines plus the γ- and ϵ-TiO
  bands synthesised with a grid of BT-Settl model atmospheres and the
  turbospectrum code. To avoid potential degeneracies in the parameter
  space, we impose a Bayesian prior on T<SUB>eff</SUB> and log g based
  on comprehensive, multi-band photometric data available for the
  sample. As a benchmark test in T<SUB>eff</SUB>, log g, and [Fe/H]
  we place special emphasis on three special subsets in our sample,
  namely 14 M dwarfs with interferometric angular diameter measurements,
  15 M+M systems, and 7 wide physical binaries harbouring an FGK-type
  primary with known metallicity.

Title: The Lines are Not Fine: Measuring Vanadium Abundances in M
    dwarfs from Hyperfine-Split Lines
Authors: Shan, Yutong; Reiners, Ansgar; Fabbian, Damian; Marfil,
   Emilio; Montes, David; Tabernero, Hugo M.; Ribas, Ignasi; Caballero,
   Jose A.; Quirrenbach, Andreas; Amado, Pedro J.; Aceituno, J.; Bejar,
   Victor J. S.; Cortes-Contreras, Miriam; Dreizler, Stefan; Hatzes,
   Artie P.; Henning, Thomas; Jeffers, Sandra V.; Kaminski, Adrian;
   Kürster, Martin; Lafarga, Marina; Morales, Juan Carlos; Nagel,
   Evangelos; Rodriguez-Lopez, Cristina; Passegger, Vera M.; Schweitzer,
   Andreas; Zechmeister, Mathias
Bibcode: 2021csss.confE.160S
Altcode:
  Cool star atmospheres present challenges to chemical abundance
  studies. To date, only a handful of elements have been quantified for
  a handful of M dwarfs. In high-resolution spectra from the CARMENES
  survey, we identify a series of dramatically hyperfine-split vanadium
  features between 800 and 910 nm, which have strong and clean profiles
  throughout the early M-dwarf range. These 'bucket-shaped' line regions
  can be well-modeled with standard model atmospheres combined with
  the latest atomic data from VALD. From these line regions, we measure
  vanadium abundances for 140 nearby early M dwarfs in the CARMENES GTO
  sample and confirm that they follow the same trend with metallicity
  as the FG-type stars in the solar neighborhood, i.e., significantly
  above predictions from galactic chemical evolution models. Exhibiting
  a tight correlation with iron, vanadium abundances show promise
  as a potential metallicity indicator for M dwarfs. We also present
  evidence that several well-known chemical studies of K dwarfs have
  systematically overestimated their vanadium abundances largely as a
  result of neglecting to model hyperfine structure, a bias that worsens
  with decreasing temperature. Our work highlights opportunities for
  robust chemical analysis of cool stars afforded by high-quality spectra
  redward of visible.

Title: Mapping stellar activity indicators across the M dwarf domain
Authors: Lafarga, Marina; Ribas, Ignasi; Reiners, Ansgar; Quirrenbach,
   Andreas; Amado, Pedro J.; Caballero, Jose A.; Azzaro, Marco;
   Béjar, Víctor J. S.; Cortés-Contreras, Miriam; Dreizler, Stefan;
   Hatzes, Artie P.; Henning, Thomas; Jeffers, Sandra V.; Kaminski,
   A.; Kürster, Martin; Montes, David; Morales, Juan Carlos; Oshagh,
   Mahmoud; Rodríguez-López, Cristina; Schöfer, Patrick; Schweitzer,
   Andreas; Zechmeister, Mathias
Bibcode: 2021csss.confE.184L
Altcode:
  Despite stellar magnetic activity being present in most cool
  stars, its effects on spectroscopic observations are still not
  well understood. Several activity indicators are routinely used to
  identify activity-related signals in radial velocity (RV) measurements,
  but not all indicators trace exactly the same effects, nor are any
  of them always effective in all stars. This poses one of the main
  obstacles for the detection and characterisation of small exoplanets,
  as magnetic activity biases RV signals. In this work, we analyse
  the temporal behaviour of RVs and a set of spectroscopic indicators
  for 98 M dwarfs observed with CARMENES, with the aim of finding a
  relation between indicator performance and stellar properties. We find
  periodic signals related to activity for 56 sample stars. The activity
  indicators behave differently depending on the mass and activity level
  of the target star, e.g., cross-correlation function bisector inverse
  slope and chromatic index are effective activity tracers for the most
  active stars in the sample, especially stars with relatively high mass,
  while for less active stars, chromospheric lines perform best. Most of
  the targets for which we cannot identify any activity-related signal
  are stars at the low-mass end of the sample, where stars are fully
  convective, and also show the lowest RV scatter. This could potentially
  hint at different manifestations of activity compared to higher-mass
  stars. Moreover, ultracool M dwarfs could be better candidates for
  planet searches than earlier types, which display higher levels of RV
  variability. Our results show that none of the indicators are effective
  activity tracers for all stars. Therefore, an analysis of a large set
  of indicators seems necessary to obtain a complete picture of stellar
  activity variability. This becomes critical when assessing the origin
  of RV signals, as not using the most effective indicators considering
  the characteristics of the star may lead to false planet claims.

Title: A Deep Learning Approach to photospheric Parameters of CARMENES
    Target Stars
Authors: Passegger, Vera Maria; Ordieres-Meré, Joaquin; Bello-García,
   Antonio; Caballero, José Antonio; Schweitzer, Andreas; Amado, Pedro
   J.; González-Marcos, Ana; Ribas, Ignasi; Reiners, Ansgar; Quirrenbach,
   Andreas; Sarro, Luis M.; Solano, Enrique; Azzaro, Marco; Bauer, Florian
   F.; Béjar, Victor J. S.; Cortés-Contreras, Miriam; Dreizler, Stefan;
   Hatzes, Artie P.; Henning, Thomas; Jeffers, Sandra V.; Kaminski,
   Adrian; Kürster, Martin; Lafarga, Marina; Marfil, Emilio; Montes,
   David; Morales, Juan Carlos; Nagel, Evangelos; Tabernero, Hugo M.;
   Zechmeister, Mathias
Bibcode: 2021csss.confE..71P
Altcode:
  We construct an individual convolutional neural network architecture
  for each of the four stellar parameters effective temperature (Teff),
  surface gravity (log g), metallicity [M/H], and rotational velocity
  (v sin i). The networks are trained on synthetic PHOENIX-ACES spectra,
  showing small training and validation errors. We apply the trained
  networks to the observed spectra of 283 M dwarfs observed with
  CARMENES. Although the network models do very well on synthetic
  spectra, we find large deviations from literature values especially
  for metallicity, due to the synthetic gap.

Title: A nearby transiting rocky exoplanet that is suitable for
    atmospheric investigation
Authors: Trifonov, T.; Caballero, J. A.; Morales, J. C.; Seifahrt, A.;
   Ribas, I.; Reiners, A.; Bean, J. L.; Luque, R.; Parviainen, H.; Pallé,
   E.; Stock, S.; Zechmeister, M.; Amado, P. J.; Anglada-Escudé, G.;
   Azzaro, M.; Barclay, T.; Béjar, V. J. S.; Bluhm, P.; Casasayas-Barris,
   N.; Cifuentes, C.; Collins, K. A.; Collins, K. I.; Cortés-Contreras,
   M.; de Leon, J.; Dreizler, S.; Dressing, C. D.; Esparza-Borges, E.;
   Espinoza, N.; Fausnaugh, M.; Fukui, A.; Hatzes, A. P.; Hellier, C.;
   Henning, Th.; Henze, C. E.; Herrero, E.; Jeffers, S. V.; Jenkins,
   J. M.; Jensen, E. L. N.; Kaminski, A.; Kasper, D.; Kossakowski, D.;
   Kürster, M.; Lafarga, M.; Latham, D. W.; Mann, A. W.; Molaverdikhani,
   K.; Montes, D.; Montet, B. T.; Murgas, F.; Narita, N.; Oshagh,
   M.; Passegger, V. M.; Pollacco, D.; Quinn, S. N.; Quirrenbach, A.;
   Ricker, G. R.; Rodríguez López, C.; Sanz-Forcada, J.; Schwarz, R. P.;
   Schweitzer, A.; Seager, S.; Shporer, A.; Stangret, M.; Stürmer, J.;
   Tan, T. G.; Tenenbaum, P.; Twicken, J. D.; Vanderspek, R.; Winn, J. N.
Bibcode: 2021Sci...371.1038T
Altcode: 2021arXiv210304950T
  Spectroscopy of transiting exoplanets can be used to investigate their
  atmospheric properties and habitability. Combining radial velocity
  (RV) and transit data provides additional information on exoplanet
  physical properties. We detect a transiting rocky planet with an
  orbital period of 1.467 days around the nearby red dwarf star Gliese
  486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii,
  with uncertainties of 5%, as determined from RV data and photometric
  light curves. The host star is at a distance of ~8.1 parsecs, has
  a J-band magnitude of ~7.2, and is observable from both hemispheres
  of Earth. On the basis of these properties and the planet’s short
  orbital period and high equilibrium temperature, we show that this
  terrestrial planet is suitable for emission and transit spectroscopy.

Title: A deep learning approach to photospheric parameters of CARMENES
    target stars
Authors: Passegger, Vera Maria; Bello-García, Antonio; Ordieres-Meré,
   Joaquin; Caballero, José Antonio; Schweitzer, Andreas; Amado, Pedro
   J.; González-Marcos, Ana; Ribas, Ignasi; Reiners, Ansgar; Quirrenbach,
   Andreas; Sarro, Luis M.; Solano, Enrique; Azzaro, Marco; Bauer, Florian
   F.; Béjar, Victor J. S.; Cortés-Contreras, Miriam; Dreizler, Stefan;
   Hatzes, Artie P.; Henning, Thomas; Jeffers, Sandra V.; Kaminski,
   Adrian; Kürster, Martin; Lafarga, Marina; Marfil, Emilio; Montes,
   David; Morales, Juan Carlos; Nagel, Evangelos; Tabernero, Hugo M.;
   Zechmeister, Mathias
Bibcode: 2021csss.confE.312P
Altcode:
  In the light of more and more new instrumentation to get a deeper
  insight into the universe, tons of data are collected. While traditional
  machine-learning methods have been used in processing stellar spectral
  data, such large new datasets are better handled with Deep Learning (DL)
  techniques. In this work, we present a Deep Convolutional Neural Network
  (CNN) approach to derive fundamental stellar parameters (effective
  temperature, surface gravity, metallicity and rotational velocity)
  from high-resolution high signal-to-noise ratio spectra. We construct
  an individual CNN architecture for each of the four parameters and
  train them on synthetic PHOENIX-ACES spectra. After that, we apply
  the trained networks to the observed spectra of 50 M dwarfs observed
  with CARMENES. The CARMENES spectrograph, installed on the 3.5 m
  telescope at the Calar Alto Observatory (Spain) has two channels,
  covering the visible (0.52 to 0.96 µm, R = 96,400) and near-infrared
  (0.96 to 1.71 µm, R = 80,600) spectral ranges. We compare our results
  to literature values, and demonstrate that our method can be used
  for stellar parameter determination without the need of having a huge
  sample of stellar spectra with known parameters, because our networks
  can be trained on synthetic spectra. Introducing Deep Transfer Learning
  (DTL) in our approach allows us to transfer external knowledge about
  the stellar parameters (e.g., from interferometry) to our training
  set and therefore improve our results compared to literature.

Title: Identification and Mitigation of a Vibrational Telescope
    Systematic with Application to Spitzer
Authors: Challener, Ryan C.; Harrington, Joseph; Jenkins, James;
   Kurtovic, Nicolás T.; Ramirez, Ricardo; McIntyre, Kathleen J.;
   Himes, Michael D.; Rodríguez, Eloy; Anglada-Escudé, Guillem;
   Dreizler, Stefan; Ofir, Aviv; Peña Rojas, Pablo A.; Ribas, Ignasi;
   Rojo, Patricio; Kipping, David; Butler, R. Paul; Amado, Pedro J.;
   Rodríguez-López, Cristina; Palle, Enric; Murgas, Felipe
Bibcode: 2021PSJ.....2....9C
Altcode: 2020arXiv201105270C
  We observed Proxima Centauri with the Spitzer Space Telescope Infrared
  Array Camera five times in 2016 and 2017 to search for transits of
  Proxima Centauri b. Following standard analysis procedures, we found
  three asymmetric, transit-like events that are now understood to be
  vibrational systematics. This systematic is correlated with the width
  of the point-response function (PRF), which we measure with rotated
  and nonrotated-Gaussian fits with respect to the detector array. We
  show that the systematic can be removed with a novel application of
  an adaptive elliptical-aperture photometry technique, and compare the
  performance of this technique with fixed and variable circular-aperture
  photometry, using both BiLinearly Interpolated Subpixel Sensitivity
  (BLISS) maps and nonbinned Pixel-Level Decorrelation (PLD). With BLISS
  maps, elliptical photometry results in a lower standard deviation
  of normalized residuals, and reduced or similar correlated noise
  when compared to circular apertures. PLD prefers variable, circular
  apertures, but generally results in more correlated noise than
  BLISS. This vibrational effect is likely present in other telescopes
  and Spitzer observations, where correction could improve results. Our
  elliptical apertures can be applied to any photometry observations,
  and may be even more effective when applied to more circular PRFs
  than Spitzer's.

Title: The CARMENES search for exoplanets around M dwarfs. LP 714-47 b
(TOI 442.01): populating the Neptune desert
Authors: Dreizler, S.; Crossfield, I. J. M.; Kossakowski, D.; Plavchan,
   P.; Jeffers, S. V.; Kemmer, J.; Luque, R.; Espinoza, N.; Pallé, E.;
   Stassun, K.; Matthews, E.; Cale, B.; Caballero, J. A.; Schlecker, M.;
   Lillo-Box, J.; Zechmeister, M.; Lalitha, S.; Reiners, A.; Soubkiou,
   A.; Bitsch, B.; Zapatero Osorio, M. R.; Chaturvedi, P.; Hatzes, A. P.;
   Ricker, G.; Vanderspek, R.; Latham, D. W.; Seager, S.; Winn, J.;
   Jenkins, J. M.; Aceituno, J.; Amado, P. J.; Barkaoui, K.; Barbieri, M.;
   Batalha, N. M.; Bauer, F. F.; Benneke, B.; Benkhaldoun, Z.; Beichman,
   C.; Berberian, J.; Burt, J.; Butler, R. P.; Caldwell, D. A.; Chintada,
   A.; Chontos, A.; Christiansen, J. L.; Ciardi, D. R.; Cifuentes, C.;
   Collins, K. A.; Collins, K. I.; Combs, D.; Cortés-Contreras, M.;
   Crane, J. D.; Daylan, T.; Dragomir, D.; Esparza-Borges, E.; Evans, P.;
   Feng, F.; Flowers, E. E.; Fukui, A.; Fulton, B.; Furlan, E.; Gaidos,
   E.; Geneser, C.; Giacalone, S.; Gillon, M.; Gonzales, E.; Gorjian,
   V.; Hellier, C.; Hidalgo, D.; Howard, A. W.; Howell, S.; Huber, D.;
   Isaacson, H.; Jehin, E.; Jensen, E. L. N.; Kaminski, A.; Kane, S. R.;
   Kawauchi, K.; Kielkopf, J. F.; Klahr, H.; Kosiarek, M. R.; Kreidberg,
   L.; Kürster, M.; Lafarga, M.; Livingston, J.; Louie, D.; Mann, A.;
   Madrigal-Aguado, A.; Matson, R. A.; Mocnik, T.; Morales, J. C.;
   Muirhead, P. S.; Murgas, F.; Nandakumar, S.; Narita, N.; Nowak,
   G.; Oshagh, M.; Parviainen, H.; Passegger, V. M.; Pollacco, D.;
   Pozuelos, F. J.; Quirrenbach, A.; Reefe, M.; Ribas, I.; Robertson,
   P.; Rodríguez-López, C.; Rose, M. E.; Roy, A.; Schweitzer, A.;
   Schlieder, J.; Shectman, S.; Tanner, A.; Şenavcı, H. V.; Teske, J.;
   Twicken, J. D.; Villasenor, J.; Wang, S. X.; Weiss, L. M.; Wittrock,
   J.; Yılmaz, M.; Zohrabi, F.
Bibcode: 2020A&A...644A.127D
Altcode: 2020arXiv201101716D
  We report the discovery of a Neptune-like planet (LP 714-47 b, P =
  4.05204 d, m<SUB>b</SUB> = 30.8 ± 1.5M<SUB>⊕</SUB>, R<SUB>b</SUB>
  = 4.7 ± 0.3 R<SUB>⊕</SUB>) located in the "hot Neptune
  desert". Confirmation of the TESS Object of Interest (TOI 442.01)
  was achieved with radial-velocity follow-up using CARMENES, ESPRESSO,
  HIRES, iSHELL, and PFS, as well as from photometric data using TESS,
  Spitzer, and ground-based photometry from MuSCAT2, TRAPPIST-South,
  MONET-South, the George Mason University telescope, the Las Cumbres
  Observatory Global Telescope network, the El Sauce telescope, the
  TÜBİTAK National Observatory, the University of Louisville Manner
  Telescope, and WASP-South. We also present high-spatial resolution
  adaptive optics imaging with the Gemini Near-Infrared Imager. The low
  uncertainties in the mass and radius determination place LP 714-47 b
  among physically well-characterised planets, allowing for a meaningful
  comparison with planet structure models. The host star LP 714-47 is
  a slowly rotating early M dwarf (T<SUB>eff</SUB> = 3950 ± 51 K)
  with a mass of 0.59 ± 0.02M<SUB>⊙</SUB> and a radius of 0.58
  ± 0.02R<SUB>⊙</SUB>. From long-term photometric monitoring and
  spectroscopic activity indicators, we determine a stellar rotation
  period of about 33 d. The stellar activity is also manifested as
  correlated noise in the radial-velocity data. In the power spectrum
  of the radial-velocity data, we detect a second signal with a period
  of 16 days in addition to the four-day signal of the planet. This
  could be shown to be a harmonic of the stellar rotation period or the
  signal of a second planet. It may be possible to tell the difference
  once more TESS data and radial-velocity data are obtained. <P
  />RV data are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/644/A127">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/644/A127</A>
  <P />Based on observations carried out at the Centro Astronómico
  Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Junta
  de Andalucía and the Instituto de Astrofísica de Andalucía (CSIC),
  on observations carried out at the European Southern Observatory
  under ESO programme 0103.C-0152(A), and data collected with the 6.5
  m Magellan Telescopes located at Las Campanas Observatory, Chile.

Title: The CARMENES M-dwarf planet survey
Authors: Quirrenbach, Andreas; CARMENES Consortium; Amado, P. J.;
   Ribas, I.; Reiners, A.; Caballero, J. A.; Aceituno, J.; Alacid, J. M.;
   Alonso-Floriano, F. J.; Anglada-Escudé, G.; Azzaro, M.; Baroch,
   D.; Bauer, F. F.; Becerril, S.; Béjar, V. J. S.; Bluhm, P.; Calvo
   Ortega, R.; Cardona Guillén, C.; Casasayas-Barris, N.; Chaturvedi, P.;
   Cifuentes, C.; Colomé, J.; Conte, D.; Cortés-Contreras, M.; Czesla,
   S.; Díez-Alonso, E.; Domínguez Fernández, A. J.; Dreizler, S.;
   Duque-Arribas, C.; Espinoza, N.; Fuhrmeister, B.; Galadí-Enríquez,
   D.; Gar´a Quintana, E.; González-Alvare, E.; González Cuesta,
   z. L.; González Hernández, J. I.; Guenther, E. W.; de Guindos,
   E.; Hatzes, A. P.; Henning, T.; Herbort, O.; Herrero, E.; Hintz,
   D.; Iglesias-Pára, J.; Jeffers, S. V.; Johnson, E. N.; de Juan, E.;
   Kaminski, A.; Kemmer, J.; Khaimova, J.; Khalafinejad, S.; Klahr, H.;
   Kossakowski, D.; Kreidberg, L.; Kürster, M.; Labarga, F.; Lafarga, M.;
   Lampón, M.; Lara, L. M.; Lillo-Box, J.; Lodieu, N.; López Gallifa,
   A.; López González, M. J.; López-Puertas, M.; Luque, R.; Marfil,
   E.; Martín-Ruiz, S.; Matthé, C.; Molaverdikhani, K.; Montes, D.;
   Morales, J. C.; Morales-Calderóon, M.; Nagel, E.; Nortmann, L.; Nowak,
   G.; Ofir, A.; Oshaghi, M.; Pallé, E.; Passegger, V. M.; Pavlov,
   A.; Pedraz, S.; Perdelwitz, V.; Perger, M.; Reffert, S.; Revilla,
   D.; Rodríguez, E.; Rodríguez López, C.; Sabotta, S.; Sadegi, S.;
   Sairam, L.; Salz, M.; Sánchez-López, A.; Sanz-Forcada, J.; Sarkis,
   P.; Schäfer, S.; Schiller, J.; Schlecker, M.; Schmitt, J. H. M. M.;
   Schöfer, P.; Schweitzer, A.; Seiferta, W.; Shan, Y.; Shulyak, D.;
   Skrzypinski, S. L.; Solano, E.; Soto, M. G.; Stahl, O.; Stangret, M.;
   Stock, S. A.; Strachan, J. B. P.; Stuber, T.; Stürmer, J.; Tabernero,
   H. M.; Tal-Or, L.; Tala-Pinto, M.; Trifonov, T.; Vanaverbeke, S.;
   Yan, F.; Zapatero Osorio, M. R.; Zechmeister, M.
Bibcode: 2020SPIE11447E..3CQ
Altcode:
  The CARMENES instrument consists of two cross-dispersed Échelle
  spectrographs, which together cover the wavelength range from 5,200
  to 17,100 Å. During its first five years of operation at the 3.5 m
  telescope on Calar Alto, Spain, it has been used for a radial-velocity
  survey of 365 M dwarfs, for follow-up radial-velocity observations
  of transiting exoplanets, and for spectroscopic studies of exoplanet
  atmospheres during transits. The CARMENES data have also yielded a
  wealth of information on the fundamental parameters and activity of
  M dwarfs. We provide an overview of the scientific results from the
  main CARMENES survey in the years 2016 to 2020.

Title: The CARMENES search for exoplanets around M dwarfs. Three
    temperate-to-warm super-Earths
Authors: Stock, S.; Nagel, E.; Kemmer, J.; Passegger, V. M.; Reffert,
   S.; Quirrenbach, A.; Caballero, J. A.; Czesla, S.; Béjar, V. J. S.;
   Cardona, C.; Díez-Alonso, E.; Herrero, E.; Lalitha, S.; Schlecker,
   M.; Tal-Or, L.; Rodríguez, E.; Rodríguez-López, C.; Ribas, I.;
   Reiners, A.; Amado, P. J.; Bauer, F. F.; Bluhm, P.; Cortés-Contreras,
   M.; González-Cuesta, L.; Dreizler, S.; Hatzes, A. P.; Henning,
   Th.; Jeffers, S. V.; Kaminski, A.; Kürster, M.; Lafarga, M.;
   López-González, M. J.; Montes, D.; Morales, J. C.; Pedraz, S.;
   Schöfer, P.; Schweitzer, A.; Trifonov, T.; Zapatero Osorio, M. R.;
   Zechmeister, M.
Bibcode: 2020A&A...643A.112S
Altcode: 2020arXiv201000474S
  We announce the discovery of two planets orbiting the M dwarfs
  GJ 251 (0.360 ± 0.015M<SUB>⊙</SUB>) and HD 238090 (0.578 ±
  0.021M<SUB>⊙</SUB>) based on CARMENES radial velocity (RV) data. In
  addition, we independently confirm with CARMENES data the existence
  of Lalande 21185 b, a planet that has recently been discovered with
  the SOPHIE spectrograph. All three planets belong to the class of
  warm or temperate super-Earths and share similar properties. The
  orbital periods are 14.24 d, 13.67 d, and 12.95 d and the minimum
  masses are 4.0 ± 0.4 M<SUB>⊕</SUB>, 6.9 ± 0.9 M<SUB>⊕</SUB>,
  and 2.7 ± 0.3 M<SUB>⊕</SUB> for GJ 251 b, HD 238090 b, and Lalande
  21185 b, respectively. Based on the orbital and stellar properties,
  we estimate equilibrium temperatures of 351.0 ± 1.4 K for GJ 251 b,
  469.6 ± 2.6 K for HD 238090 b, and 370.1 ± 6.8 K for Lalande 21185
  b. For the latter we resolve the daily aliases that were present in
  the SOPHIE data and that hindered an unambiguous determination of the
  orbital period. We find no significant signals in any of our spectral
  activity indicators at the planetary periods. The RV observations
  were accompanied by contemporaneous photometric observations. We
  derive stellar rotation periods of 122.1 ± 2.2 d and 96.7 ± 3.7
  d for GJ 251 and HD 238090, respectively. The RV data of all three
  stars exhibit significant signals at the rotational period or its
  first harmonic. For GJ 251 and Lalande 21185, we also find long-period
  signals around 600 d, and 2900 d, respectively, which we tentatively
  attribute to long-term magnetic cycles. We apply a Bayesian approach to
  carefully model the Keplerian signals simultaneously with the stellar
  activity using Gaussian process regression models and extensively
  search for additional significant planetary signals hidden behind
  the stellar activity. Current planet formation theories suggest
  that the three systems represent a common architecture, consistent
  with formation following the core accretion paradigm. <P />Tables
  D.1-D.3 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/643/A112">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/643/A112</A>

Title: Leveraging HST with MUSE - I. Sodium abundance variations
    within the 2-Gyr-old cluster NGC 1978
Authors: Saracino, S.; Kamann, S.; Usher, C.; Bastian, N.; Martocchia,
   S.; Lardo, C.; Latour, M.; Cabrera-Ziri, I.; Dreizler, S.; Giesers,
   B.; Husser, T. -O.; Kacharov, N.; Salaris, M.
Bibcode: 2020MNRAS.498.4472S
Altcode: 2020arXiv200903320S
  Nearly all of the well-studied ancient globular clusters (GCs), in
  the Milky Way and in nearby galaxies, show star-to-star variations in
  specific elements (e.g. He, C, N, O, Na, and Al), known as 'multiple
  populations' (MPs). However, MPs are not restricted to ancient clusters,
  with massive clusters down to ~2 Gyr showing signs of chemical
  variations. This suggests that young and old clusters share the same
  formation mechanism but most of the work to date on younger clusters has
  focused on N variations. Initial studies even suggested that younger
  clusters may not host spreads in other elements beyond N (e.g. Na),
  calling into question whether these abundance variations share the
  same origin as in the older GCs. In this work, we combine Hubble Space
  Telescope (HST) photometry with Very Large Telescope (VLT)/Multi-Unit
  Spectroscopic Explorer (MUSE) spectroscopy of a large sample of red
  giant branch (RGB) stars (338) in the Large Magellanic Cloud cluster
  NGC 1978, the youngest globular to date with reported MPs in the form
  of N spreads. By combining the spectra of individual RGB stars into
  N-normal and N-enhanced samples, based on the 'chromosome map' derived
  from HST, we search for mean abundance variations. Based on the NaD
  line, we find a Na difference of Δ[Na/Fe] = 0.07 ± 0.01 between the
  populations. While this difference is smaller than typically found in
  ancient GCs (which may suggest a correlation with age), this result
  further confirms that the MP phenomenon is the same, regardless of
  cluster age and host galaxy. As such, these young clusters offer some
  of the strictest tests for theories on the origin of MPs.

Title: Leveraging HST with MUSE: II. Na-abundance variations in
    intermediate age star clusters
Authors: Martocchia, S.; Kamann, S.; Saracino, S.; Usher, C.; Bastian,
   N.; Rejkuba, M.; Latour, M.; Lardo, C.; Cabrera-Ziri, I.; Dreizler,
   S.; Kacharov, N.; Kozhurina-Platais, V.; Larsen, S.; Mancino, S.;
   Platais, I.; Salaris, M.
Bibcode: 2020MNRAS.499.1200M
Altcode: 2020arXiv200910023M; 2020MNRAS.tmp.2740M
  Ancient (&gt;10 Gyr) globular clusters (GCs) show chemical abundance
  variations in the form of patterns among certain elements, e.g. N
  correlates with Na and anticorrelates with O. Recently, N abundance
  spreads have also been observed in massive star clusters that are
  significantly younger than old GCs, down to an age of ~2 Gyr. However,
  so far N has been the only element found to vary in such young
  objects. We report here the presence of Na abundance variations in
  the intermediate age massive star clusters NGC 416 (~6.5 Gyr old) and
  Lindsay 1 (~7.5 Gyr old) in the Small Magellanic Cloud, by combining
  Hubble Space Telescope (HST) and European Southern Observatory Very
  Large Telescope MUSE observations. Using HST photometry, we were able to
  construct 'chromosome maps' and separate subpopulations with different
  N content, in the red giant branch of each cluster. MUSE spectra of
  individual stars belonging to each population were combined, resulting
  in high signal-to-noise spectra representative of each population,
  which were compared to search for mean differences in Na. We find a mean
  abundance variation of Δ[Na/Fe] = 0.18 ± 0.04 dex for NGC 416 and
  Δ[Na/Fe] = 0.24 ± 0.05 dex for Lindsay 1. In both clusters, we find
  that the population that is enhanced in N is also enhanced in Na, which
  is the same pattern to the one observed in ancient GCs. Furthermore,
  we detect a bimodal distribution of core-helium-burning red clump (RC)
  giants in the UV colour-magnitude diagram of NGC 416. A comparison of
  the stacked MUSE spectra of the two RCs shows the same mean Na abundance
  difference between the two populations. The results reported in this
  work are a crucial hint that star clusters of a large age range share
  the same origin: they are the same types of objects, but only separated
  in age.

Title: VizieR Online Data Catalog: LP714-47 (TOI 442) radial velocity
    curve (Dreizler+, 2020)
Authors: Dreizler, S.; Crossfield, I. J. M.; Kossakowski, D.; Plavchan,
   P.; Jeffers, S. V.; Kemmer, J.; Luque, R.; Espinoza, N.; Palle, E.;
   Stassun, K.; Matthews, E.; Cale, B.; Caballero, J. A.; Schlecker, M.;
   Lillo-Box, J.; Zechmeister, M.; Lalitha, S.; Reiners, A.; Soubkiou,
   A.; Bitsch, B.; Zapatero Osorio, M. R.; Chaturvedi, P.; Hatzes, A. P.;
   Ricker, G.; Vanderspek, R.; Latham, D. W.; Seager, S.; Winn, J.;
   Jenkins, J. M.; Aceituno, J.; Amado, P. J.; Barkaoui, K.; Barbieri, M.;
   Batalha, N. M.; Bauer, F. F.; Benneke, B.; Benkhaldoun, Z.; Beichman,
   C.; Berberian, J.; Burt, J.; Butler, R. P.; Caldwell, D. A.; Chintada,
   A.; Chontos, A.; Christiansen, J. L.; Ciardi, D. R.; Cifuentes, C.;
   Collins, K. A.; Collins, K. I.; Combs, D.; Cortes-Contreras, M.;
   Crane, J. D.; Daylan, T.; Dragomir, D.; Esparza-Borges, E.; Evans,
   P.; Feng, F.; Flowers, E. E.; Fukui, A.; Fulton, B.; Furlan, E.;
   Gaidos, E.; Geneser, C.; Giacalone, S.; Gillon, M.; Gonzales, E.;
   Gorjian, V.; Hellier, C.; Hidalgo, D.; Howard, A. W.; Howell, S.;
   Huber, D.; Isaacson, H.; Jehin, E.; Jensen, E. L. N.; Kaminski, A.;
   Kane, S. R.; Kawauchi, K.; Kielkopf, J. F.; Klahr, H.; Kosiarek,
   M. R.; Kreidberg, L.; Kuerster, M.; Lafarga, M.; Livingston, J.;
   Louie, D.; Mann, A.; Madrigal-Aguado, A.; Matson, R. A.; Mocnik,
   T.; Morales, J. C.; Muirhead, P. S.; Murgas, F.; Nandakumar, S.;
   Narita, N.; Nowak, G.; Oshagh, M.; Parviainen, H.; Passegger, V. M.;
   Pollacco, D.; Pozuelos, F. J.; Quirrenbach, A.; Reefe, M.; Ribas, I.;
   Robertson, P.; Rodriguez-Lopez, C.; Rose, M. E.; Roy, A.; Schweitzer,
   A.; Schlieder, J.; Shectman, S.; Tanner, A.; Senavci, H. V.; Teske, J.;
   Twicken, J. D.; Villasenor, J.; Wang, S. X.; Weiss, L. M.; Wittrock,
   J.; Yilmaz, M.; Zohrabi, F.
Bibcode: 2020yCat..36440127D
Altcode:
  High-resolution follow-up spectroscopy of the TESS planet candidates
  is arranged by the TESS follow-up programme (TFOP), "Precise Radial
  Velocities" SG4 subgroup. <P />We obtained High-resolution follow-up
  spectroscopy for LP714-47 with CARMENES-VIS, CARMENES-NIR, ESPRESSO,
  HIRES, iSHELL, and PFS. The observations began at mid February 2019,
  just after the announcement of the transiting planet candidate, and
  ended in January 2020. In this period, we collected 102 spectra. The
  spectral resolution and the number of spectra obtained by the individual
  instruments are listed in Table 1 of the paper. <P />The table contains
  the time of observation as Barycentric Julian Date in units of days,
  the measure radial velocities in unites of m/s, the measurement
  uncertainties measured in m/s, and the instrument name. <P />(1
  data file).

Title: Discovery of a hot, transiting, Earth-sized planet and a second
    temperate, non-transiting planet around the M4 dwarf GJ 3473 (TOI-488)
Authors: Kemmer, J.; Stock, S.; Kossakowski, D.; Kaminski, A.;
   Molaverdikhani, K.; Schlecker, M.; Caballero, J. A.; Amado, P. J.;
   Astudillo-Defru, N.; Bonfils, X.; Ciardi, D.; Collins, K. A.; Espinoza,
   N.; Fukui, A.; Hirano, T.; Jenkins, J. M.; Latham, D. W.; Matthews,
   E. C.; Narita, N.; Pallé, E.; Parviainen, H.; Quirrenbach, A.;
   Reiners, A.; Ribas, I.; Ricker, G.; Schlieder, J. E.; Seager, S.;
   Vanderspek, R.; Winn, J. N.; Almenara, J. M.; Béjar, V. J. S.;
   Bluhm, P.; Bouchy, F.; Boyd, P.; Christiansen, J. L.; Cifuentes,
   C.; Cloutier, R.; Collins, K. I.; Cortés-Contreras, M.; Crossfield,
   I. J. M.; Crouzet, N.; de Leon, J. P.; Della-Rose, D. D.; Delfosse,
   X.; Dreizler, S.; Esparza-Borges, E.; Essack, Z.; Forveille, Th.;
   Figueira, P.; Galadí-Enríquez, D.; Gan, T.; Glidden, A.; Gonzales,
   E. J.; Guerra, P.; Harakawa, H.; Hatzes, A. P.; Henning, Th.; Herrero,
   E.; Hodapp, K.; Hori, Y.; Howell, S. B.; Ikoma, M.; Isogai, K.;
   Jeffers, S. V.; Kürster, M.; Kawauchi, K.; Kimura, T.; Klagyivik,
   P.; Kotani, T.; Kurokawa, T.; Kusakabe, N.; Kuzuhara, M.; Lafarga,
   M.; Livingston, J. H.; Luque, R.; Matson, R.; Morales, J. C.; Mori,
   M.; Muirhead, P. S.; Murgas, F.; Nishikawa, J.; Nishiumi, T.; Omiya,
   M.; Reffert, S.; Rodríguez López, C.; Santos, N. C.; Schöfer, P.;
   Schwarz, R. P.; Shiao, B.; Tamura, M.; Terada, Y.; Twicken, J. D.;
   Ueda, A.; Vievard, S.; Watanabe, N.; Zechmeister, M.
Bibcode: 2020A&A...642A.236K
Altcode: 2020arXiv200910432K
  We present the confirmation and characterisation of GJ 3473 b (G 50-16,
  TOI-488.01), a hot Earth-sized planet orbiting an M4 dwarf star, whose
  transiting signal (P = 1.1980035 ± 0.0000018 d) was first detected
  by the Transiting Exoplanet Survey Satellite (TESS). Through a joint
  modelling of follow-up radial velocity observations with CARMENES, IRD,
  and HARPS together with extensive ground-based photometric follow-up
  observations with LCOGT, MuSCAT, and MuSCAT2, we determined a precise
  planetary mass, M<SUB>b</SUB> = 1.86 ± 0.30 M<SUB>⊕</SUB>, and
  radius, R<SUB>b</SUB> = 1.264 ± 0.050 R<SUB>⊕</SUB>. Additionally,
  we report the discovery of a second, temperate, non-transiting planet
  in the system, GJ 3473 c, which has a minimum mass, M<SUB>c</SUB> sin
  i = 7.41 ± 0.91 M<SUB>⊕</SUB>, and orbital period, P<SUB>c</SUB>
  = 15.509 ± 0.033 d. The inner planet of the system, GJ 3473 b,
  is one of the hottest transiting Earth-sized planets known thus
  far, accompanied by a dynamical mass measurement, which makes it a
  particularly attractive target for thermal emission spectroscopy. <P
  />RV data are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/642/A236">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/642/A236</A>

Title: The CARMENES search for exoplanets around M dwarfs. Two
    planets on opposite sides of the radius gap transiting the nearby
    M dwarf LTT 3780
Authors: Nowak, G.; Luque, R.; Parviainen, H.; Pallé, E.;
   Molaverdikhani, K.; Béjar, V. J. S.; Lillo-Box, J.; Rodríguez-López,
   C.; Caballero, J. A.; Zechmeister, M.; Passegger, V. M.; Cifuentes,
   C.; Schweitzer, A.; Narita, N.; Cale, B.; Espinoza, N.; Murgas, F.;
   Hidalgo, D.; Zapatero Osorio, M. R.; Pozuelos, F. J.; Aceituno, F. J.;
   Amado, P. J.; Barkaoui, K.; Barrado, D.; Bauer, F. F.; Benkhaldoun,
   Z.; Caldwell, D. A.; Casasayas Barris, N.; Chaturvedi, P.; Chen, G.;
   Collins, K. A.; Collins, K. I.; Cortés-Contreras, M.; Crossfield,
   I. J. M.; de León, J. P.; Díez Alonso, E.; Dreizler, S.; El Mufti,
   M.; Esparza-Borges, E.; Essack, Z.; Fukui, A.; Gaidos, E.; Gillon,
   M.; Gonzales, E. J.; Guerra, P.; Hatzes, A.; Henning, Th.; Herrero,
   E.; Hesse, K.; Hirano, T.; Howell, S. B.; Jeffers, S. V.; Jehin, E.;
   Jenkins, J. M.; Kaminski, A.; Kemmer, J.; Kielkopf, J. F.; Kossakowski,
   D.; Kotani, T.; Kürster, M.; Lafarga, M.; Latham, D. W.; Law, N.;
   Lissauer, J. J.; Lodieu, N.; Madrigal-Aguado, A.; Mann, A. W.; Massey,
   B.; Matson, R. A.; Matthews, E.; Montañés-Rodríguez, P.; Montes,
   D.; Morales, J. C.; Mori, M.; Nagel, E.; Oshagh, M.; Pedraz, S.;
   Plavchan, P.; Pollacco, D.; Quirrenbach, A.; Reffert, S.; Reiners,
   A.; Ribas, I.; Ricker, G. R.; Rose, M. E.; Schlecker, M.; Schlieder,
   J. E.; Seager, S.; Stangret, M.; Stock, S.; Tamura, M.; Tanner, A.;
   Teske, J.; Trifonov, T.; Twicken, J. D.; Vanderspek, R.; Watanabe,
   D.; Wittrock, J.; Ziegler, C.; Zohrabi, F.
Bibcode: 2020A&A...642A.173N
Altcode: 2020arXiv200301140N
  We present the discovery and characterisation of two transiting
  planets observed by the Transiting Exoplanet Survey Satellite
  (TESS) orbiting the nearby (d<SUB>⋆</SUB> ≈ 22 pc), bright (J
  ≈ 9 mag) M3.5 dwarf LTT 3780 (TOI-732). We confirm both planets
  and their association with LTT 3780 via ground-based photometry and
  determine their masses using precise radial velocities measured with
  the CARMENES spectrograph. Precise stellar parameters determined
  from CARMENES high-resolution spectra confirm that LTT 3780 is a
  mid-M dwarf with an effective temperature of T<SUB>eff</SUB> = 3360
  ± 51 K, a surface gravity of log g<SUB>⋆</SUB> = 4.81 ± 0.04
  (cgs), and an iron abundance of [Fe/H] = 0.09 ± 0.16 dex, with an
  inferred mass of M<SUB>⋆</SUB> = 0.379 ± 0.016M<SUB>⊙</SUB>
  and a radius of R<SUB>⋆</SUB> = 0.382 ± 0.012R<SUB>⊙</SUB>. The
  ultra-short-period planet LTT 3780 b (P<SUB>b</SUB> = 0.77 d) with
  a radius of 1.35<SUB>-0.06</SUB><SUP>+0.06</SUP> R<SUB>⊕</SUB>,
  a mass of 2.34<SUP>-0.23</SUP><SUB>+0.24</SUB> M<SUB>⊕</SUB>, and a
  bulk density of 5.24<SUB>-0.81</SUB><SUP>+0.94</SUP> g cm<SUP>-3</SUP>
  joins the population of Earth-size planets with rocky, terrestrial
  composition. The outer planet, LTT 3780 c, with an orbital period of
  12.25 d, radius of 2.42<SUB>-0.10</SUB><SUP>+0.10</SUP> R<SUB>⊕</SUB>,
  mass of 6.29<SUB>-0.61</SUB><SUP>+0.63</SUP> M<SUB>⊕</SUB>, and
  mean density of 2.45<SUB>-0.37</SUB><SUP>+0.44</SUP> g cm<SUP>-3</SUP>
  belongs to the population of dense sub-Neptunes. With the two planets
  located on opposite sides of the radius gap, this planetary system
  is anexcellent target for testing planetary formation, evolution,
  and atmospheric models. In particular, LTT 3780 c is an ideal object
  for atmospheric studies with the James Webb Space Telescope (JWST).

Title: The CARMENES search for exoplanets around M dwarfs. Rubidium
    abundances in nearby cool stars
Authors: Abia, C.; Tabernero, H. M.; Korotin, S. A.; Montes, D.;
   Marfil, E.; Caballero, J. A.; Straniero, O.; Prantzos, N.; Ribas,
   I.; Reiners, A.; Quirrenbach, A.; Amado, P. J.; Béjar, V. J. S.;
   Cortés-Contreras, M.; Dreizler, S.; Henning, Th.; Jeffers, S. V.;
   Kaminski, A.; Kürster, M.; Lafarga, M.; López-Gallifa, Á.; Morales,
   J. C.; Nagel, E.; Passegger, V. M.; Pedraz, S.; Rodríguez López,
   C.; Schweitzer, A.; Zechmeister, M.
Bibcode: 2020A&A...642A.227A
Altcode: 2020arXiv200900876A
  Due to their ubiquity and very long main-sequence lifetimes, abundance
  determinations in M dwarfs provide a powerful and alternative tool to
  GK dwarfs to study the formation and chemical enrichment history of our
  Galaxy. In this study, abundances of the neutron-capture elements Rb,
  Sr, and Zr are derived, for the first time, in a sample of nearby M
  dwarfs. We focus on stars in the metallicity range - 0.5 ≲ [Fe/H]
  ≲ +0.3, an interval poorly explored for Rb abundances in previous
  analyses. To do this we use high-resolution, high-signal-to-noise-ratio,
  optical and near-infrared spectra of 57 M dwarfs observed with
  CARMENES. The resulting [Sr/Fe] and [Zr/Fe] ratios for most M dwarfs
  are almost constant at about the solar value, and are identical to
  those found in GK dwarfs of the same metallicity. However, for Rb we
  find systematic underabundances ([Rb/Fe] &lt; 0.0) by a factor two on
  average. Furthermore, a tendency is found for Rb - but not for other
  heavy elements (Sr, Zr) - to increase with increasing metallicity
  such that [Rb/Fe] ≳ 0.0 is attained at metallicities higher than
  solar. These are surprising results, never seen for any other heavy
  element, and are difficult to understand within the formulation of
  the s- and r-processes, both contributing sources to the Galactic
  Rb abundance. We discuss the reliability of these findings for
  Rb in terms of non-LTE (local thermodynamic equilibrium) effects,
  stellar activity, or an anomalous Rb abundance in the Solar System,
  but no explanation is found. We then interpret the full observed [Rb/Fe]
  versus [Fe/H] trend within the framework of theoretical predictions from
  state-of-the-art chemical evolution models for heavy elements, but a
  simple interpretation is not found either. In particular, the possible
  secondary behaviour of the [Rb/Fe] ratio at super-solar metallicities
  would require a much larger production of Rb than currently predicted
  in AGB stars through the s-process without overproducing Sr and Zr.

Title: The CARMENES search for exoplanets around M dwarfs. A deep
    learning approach to determine fundamental parameters of target stars
Authors: Passegger, V. M.; Bello-García, A.; Ordieres-Meré, J.;
   Caballero, J. A.; Schweitzer, A.; González-Marcos, A.; Ribas, I.;
   Reiners, A.; Quirrenbach, A.; Amado, P. J.; Azzaro, M.; Bauer, F. F.;
   Béjar, V. J. S.; Cortés-Contreras, M.; Dreizler, S.; Hatzes, A. P.;
   Henning, Th.; Jeffers, S. V.; Kaminski, A.; Kürster, M.; Lafarga,
   M.; Marfil, E.; Montes, D.; Morales, J. C.; Nagel, E.; Sarro, L. M.;
   Solano, E.; Tabernero, H. M.; Zechmeister, M.
Bibcode: 2020A&A...642A..22P
Altcode: 2020arXiv200801186P
  Existing and upcoming instrumentation is collecting large amounts
  of astrophysical data, which require efficient and fast analysis
  techniques. We present a deep neural network architecture to analyze
  high-resolution stellar spectra and predict stellar parameters such as
  effective temperature, surface gravity, metallicity, and rotational
  velocity. With this study, we firstly demonstrate the capability of
  deep neural networks to precisely recover stellar parameters from
  a synthetic training set. Secondly, we analyze the application of
  this method to observed spectra and the impact of the synthetic gap
  (i.e., the difference between observed and synthetic spectra) on the
  estimation of stellar parameters, their errors, and their precision. Our
  convolutional network is trained on synthetic PHOENIX-ACES spectra
  in different optical and near-infrared wavelength regions. For
  each of the four stellar parameters, T<SUB>eff</SUB>, log g, [M/H],
  and v sin i, we constructed a neural network model to estimate each
  parameter independently. We then applied this method to 50 M dwarfs with
  high-resolution spectra taken with CARMENES (Calar Alto high-Resolution
  search for M dwarfs with Exo-earths with Near-infrared and optical
  Échelle Spectrographs), which operates in the visible (520-960 nm)
  and near-infrared wavelength range (960-1710 nm) simultaneously. Our
  results are compared with literature values for these stars. They
  show mostly good agreement within the errors, but also exhibit large
  deviations in some cases, especially for [M/H], pointing out the
  importance of a better understanding of the synthetic gap.

Title: VizieR Online Data Catalog: CARMENES VIS RVs of 3 M dwarfs
    (Stock+, 2020)
Authors: Stock, S.; Nagel, E.; Kemmer, J.; Passegger, V. M.; Reffert,
   S.; Quirrenbach, A.; Caballero, J. A.; Czesla, S.; Bejar, V. J. S.;
   Cardona, C.; Diez-Alonso, E.; Herrero, E.; Lalitha, S.; Schlecker, M.;
   Tal-Or, L.; Rodriguez, E.; Rodriguez-Lopez, C.; Ribas, I.; Reiners,
   A.; Amado, P. J.; Bauer, F. F.; Bluhm, P.; Cortes-Contreras, M.;
   Gonzalez-Cuesta, L.; Dreizler, S.; Hatzes, A. P.; Henning, T.; Jeffers,
   S. V.; Kaminski, A.; Kuerster, M.; Lafarga, M.; Lopez-Gonzalez, M. J.;
   Montes, D.; Morales, J. C.; Pedraz, S.; Schoefer, P.; Schweitzer,
   A.; Trifonov, T.; Zapatero Osorio, M. R.; Zechmeister, M.
Bibcode: 2020yCat..36430112S
Altcode:
  We acquired spectra with CARMENES (Quirrenbach et al., 2014, in
  Proc. SPIE, Vol. 9147, Ground-based and Airborne Instrumentation for
  Astronomy V, 91471F), a high-resolution precise echelle spectrograph
  mounted at the 3.5m telescope at the Calar Alto Observatory in Spain. <P
  />(3 data files).

Title: VizieR Online Data Catalog: GJ 3473 (TOI-488) radial velocity
    curve (Kemmer+, 2020)
Authors: Kemmer, J.; Stock, S.; Kossakowski, D.; Kaminski, A.;
   Molaverdikhani, K.; Schlecker, M.; Caballero, J. A.; Amado, P. J.;
   Astudillo-Defru, N.; Bonfils, X.; Ciardi, D.; Collins, K. A.; Espinoza,
   N.; Fukui, A.; Hirano, T.; Jenkins, J. M.; Latham, D. W.; Matthews,
   E. C.; Narita, N.; Palle, E.; Parviainen, H.; Quirrenbach, A.; Reiners,
   A.; Ribas, I.; Ricker, G.; Schlieder, J. E.; Seager, S.; Vanderspek,
   R.; Winn, J. N.; Almenara, J. M.; Bejar, V. J. S.; Bluhm, P.; Bouchy,
   F.; Boyd, P.; Christiansen, J. L.; Cifuentes, C.; Cloutier, R.;
   Collins, K. I.; Cortes-Contreras, M.; I. J. M., Crossfield; Crouzet,
   N.; de, Leon J. P.; Della-Rose, D. D.; Delfosse, X.; Dreizler,
   S.; Esparza-Borges, E.; Essack, Z.; Forveille, T.; Figueira, P.;
   Galadi-Enriquez, D.; Gan, T.; Glidden, A.; Gonzales, E. J.; Guerra,
   P.; Harakawa, H.; Hatzes, A. P.; Henning, T.; Herrero, E.; Hodapp,
   K.; Hori, Y.; Howell, S. B.; Ikoma, M.; Isogai, K.; Jeffers, S. V.;
   Kuerster, M.; Kawauchi, K.; Kimura, T.; Klagyivik, P.; Kotani, T.;
   Kurokawa, T.; Kusakabe, N.; Kuzuhara, M.; Lafarga, M.; Livingston,
   J. H.; Luqu!, E. R.; Mat Son, R.; Morales, J. C.; Mori, M.; Muirhead,
   P. S.; Murgas, F.; Nishikawa, J.; Nishiumi, T.; Omiya, M.; Reffert,
   S.; Rodriguez Lopez, C.; Santos, N. C.; Schoefer, P.; Schwarz, R. P.;
   Shiao, B.; Tamura, M.; Terada, Y.; Twicken, J. D.; Ueda, A.; Vievard,
   S.; Watanabe, N.; Zechmeister, M.
Bibcode: 2020yCat..36420236K
Altcode:
  High-resolution follow-up spectroscopy of the TESS planet candidates
  is arranged by the TESS follow-up programme (TFOP), "Precise Radial
  Velocities" SG4 subgroup. <P />We observed GJ 3473 with CARMENES. The
  observations began at the end of March 2019, just after the announcement
  of the transiting planet candidate, and ended in January 2020. In this
  period, we collected 67 pairs of VIS and NIR spectra with exposure
  times of about 30 min each. <P />In the course of the Subaru IRD TESS
  Intensive Follow-up Project (proposal S19A-069I), we observed GJ 3473
  with the InfraRed Doppler spectrograph (IRD). A total of 56 frames were
  acquired for GJ 3473 by IRD on 12 different nights between April 2019
  and December 2019. <P />GJ 3473 was also observed by the High Accuracy
  Radial velocity Planet Searcher (HARPS). The 32 observations presented
  here were taken between May 2019 and March 2020. <P />(1 data file).

Title: The CARMENES search for exoplanets around M dwarfs. Convective
    shift and starspot constraints from chromatic radial velocities
Authors: Baroch, D.; Morales, J. C.; Ribas, I.; Herrero, E.;
   Rosich, A.; Perger, M.; Anglada-Escudé, G.; Reiners, A.; Caballero,
   J. A.; Quirrenbach, A.; Amado, P. J.; Jeffers, S. V.; Cifuentes,
   C.; Passegger, V. M.; Schweitzer, A.; Lafarga, M.; Bauer, F. F.;
   Béjar, V. J. S.; Colomé, J.; Cortés-Contreras, M.; Dreizler, S.;
   Galadí-Enríquez, D.; Hatzes, A. P.; Henning, Th.; Kaminski, A.;
   Kürster, M.; Montes, D.; Rodríguez-López, C.; Zechmeister, M.
Bibcode: 2020A&A...641A..69B
Altcode: 2020arXiv200616608B
  Context. Variability caused by stellar activity represents a challenge
  to the discovery and characterization of terrestrial exoplanets and
  complicates the interpretation of atmospheric planetary signals. <BR
  /> Aims: We aim to use a detailed modeling tool to reproduce the
  effect of active regions on radial velocity measurements, which aids
  the identification of the key parameters that have an impact on the
  induced variability. <BR /> Methods: We analyzed the effect of stellar
  activity on radial velocities as a function of wavelength by simulating
  the impact of the properties of spots, shifts induced by convective
  motions, and rotation. We focused our modeling effort on the active
  star <ASTROBJ>YZ CMi</ASTROBJ> (GJ 285), which was photometrically
  and spectroscopically monitored with CARMENES and the Telescopi Joan
  Oró. <BR /> Results: We demonstrate that radial velocity curves
  at different wavelengths yield determinations of key properties of
  active regions, including spot-filling factor, temperature contrast,
  and location, thus solving the degeneracy between them. Most notably,
  our model is also sensitive to convective motions. Results indicate a
  reduced convective shift for M dwarfs when compared to solar-type stars
  (in agreement with theoretical extrapolations) and points to a small
  global convective redshift instead of blueshift. <BR /> Conclusions:
  Using a novel approach based on simultaneous chromatic radial velocities
  and light curves, we can set strong constraints on stellar activity,
  including an elusive parameter such as the net convective motion effect.

Title: The CARMENES search for exoplanets around M dwarfs. Variability
    of the He I line at 10 830 Å
Authors: Fuhrmeister, B.; Czesla, S.; Hildebrandt, L.; Nagel, E.;
   Schmitt, J. H. M. M.; Jeffers, S. V.; Caballero, J. A.; Hintz, D.;
   Johnson, E. N.; Schöfer, P.; Zechmeister, M.; Reiners, A.; Ribas, I.;
   Amado, P. J.; Quirrenbach, A.; Nortmann, L.; Bauer, F. F.; Béjar,
   V. J. S.; Cortés-Contreras, M.; Dreizler, S.; Galadí-Enríquez,
   D.; Hatzes, A. P.; Kaminski, A.; Kürster, M.; Lafarga, M.; Montes, D.
Bibcode: 2020A&A...640A..52F
Altcode: 2020arXiv200609372F
  The He I infrared (IR) triplet at 10 830 Å is known as an activity
  indicator in solar-type stars and has become a primary diagnostic in
  exoplanetary transmission spectroscopy. He I IR lines are a tracer
  of the stellar extreme-ultraviolet irradiation from the transition
  region and corona. We study the variability of the He I triplet lines
  in a spectral time series of 319 M dwarf stars that was obtained with
  the CARMENES high-resolution optical and near-infrared spectrograph
  at Calar Alto. We detect He I IR line variability in 18% of our
  sample stars, all of which show Hα in emission. Therefore, we find
  detectable He I variability in 78% of the sub-sample of stars with
  Hα emission. Detectable variability is strongly concentrated in the
  latest spectral sub-types, where the He I lines during quiescence
  are typically weak. The fraction of stars with detectable He I
  variation remains lower than 10% for stars earlier than M3.0 V,
  while it exceeds 30% for the later spectral sub-types. Flares are
  accompanied by particularly pronounced line variations, including
  strongly broadened lines with red and blue asymmetries. However,
  we also find evidence for enhanced He I absorption, which is
  potentially associated with increased high-energy irradiation levels
  at flare onset. Generally, He I and Hα line variations tend to be
  correlated, with Hα being the most sensitive indicator in terms
  of pseudo-equivalent width variation. This makes the He I triplet
  a favourable target for planetary transmission spectroscopy. <P
  />Full Table 2 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/640/A52">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/640/A52</A>

Title: The CARMENES search for exoplanets around M dwarfs. Measuring
precise radial velocities in the near infrared: The example of the
    super-Earth CD Cet b
Authors: Bauer, F. F.; Zechmeister, M.; Kaminski, A.; Rodríguez
   López, C.; Caballero, J. A.; Azzaro, M.; Stahl, O.; Kossakowski,
   D.; Quirrenbach, A.; Becerril Jarque, S.; Rodríguez, E.; Amado,
   P. J.; Seifert, W.; Reiners, A.; Schäfer, S.; Ribas, I.; Béjar,
   V. J. S.; Cortés-Contreras, M.; Dreizler, S.; Hatzes, A.; Henning,
   T.; Jeffers, S. V.; Kürster, M.; Lafarga, M.; Montes, D.; Morales,
   J. C.; Schmitt, J. H. M. M.; Schweitzer, A.; Solano, E.
Bibcode: 2020A&A...640A..50B
Altcode: 2020arXiv200601684B
  The high-resolution, dual channel, visible and near-infrared
  spectrograph CARMENES offers exciting opportunities for stellar
  and exoplanetary research on M dwarfs. In this work we address the
  challenge of reaching the highest radial velocity precision possible
  with a complex, actively cooled, cryogenic instrument, such as the
  near-infrared channel. We describe the performance of the instrument
  and the work flow used to derive precise Doppler measurements from
  the spectra. The capability of both CARMENES channels to detect
  small exoplanets is demonstrated with the example of the nearby
  M5.0 V star CD Cet (GJ 1057), around which we announce a super-Earth
  (4.0 ± 0.4 M<SUB>⊕</SUB>) companion on a 2.29 d orbit. <P />Based
  on observations collected at the Centro Astronómico Hispano Alemán
  (CAHA) at Calar Alto, Almería, Spain, operated jointly by the Junta de
  Andalucía and the Instituto de Astrofísica de Andalucía (CSIC). <P
  />Based on observations collected at the European Southern Observatory,
  Paranal, Chile, under program 0103.C-0152(A), and La Silla, Chile,
  under programs 072.C-0488(E) and 183.C-0437(A).

Title: Stellar atmospheric parameters of FGK-type stars (EW method)
    and M-type stars (spectral synthesis) from high-resolution optical
    and near-infrared CARMENES spectra
Authors: Marfil, E.; Tabernero, H. M.; Montes, D.; Caballero, J. A.;
   Lázaro-Barrasa, F. J.; González Hernández, J. I.; Soto, M. G.;
   Nagel, E.; Kaminski, A.; Reiners, A.; Ribas, I.; Quirrenbach, A.;
   Amado, P. J.; Bauer, F. F.; Cortés-Contreras, M.; Dreizler, S.;
   Jeffers, S. V.; Kürster, M.; Lafarga, M.; Morales, J. C.; Passegger,
   V. M.; Schweitzer, A.; Zechmeister, M.
Bibcode: 2020sea..confE.156M
Altcode:
  We aim to review the equivalent width (EW) method and the spectral
  synthesis technique to derive stellar atmospheric parameters of
  FGKM-type stars in light of the optical and near-infrared spectra
  obtained with CARMENES, the high-resolution, double-channel
  spectrograph installed at the 3.5 m telescope at the Calar Alto
  Observatory (Almería, Spain). On the one hand, we show the results
  for 65 FGK-type stars observed with CARMENES and analysed with the
  S TE P AR code, a Python implementation of the EW method, placing
  special emphasis on the impact of the near-infrared wavelength region
  on the parameter computations. On the other hand, we also highlight
  the stellar atmospheric parameters obtained for the target M dwarfs in
  the CARMENES Guaranteed Time Observations (GTO) programme by means of
  the spectral synthesis technique as implemented in the SteParSyn code.

Title: Precise mass and radius of a transiting super-Earth planet
orbiting the M dwarf TOI-1235: a planet in the radius gap?
Authors: Bluhm, P.; Luque, R.; Espinoza, N.; Pallé, E.; Caballero,
   J. A.; Dreizler, S.; Livingston, J. H.; Mathur, S.; Quirrenbach,
   A.; Stock, S.; Van Eylen, V.; Nowak, G.; López, E. D.; Csizmadia,
   Sz.; Zapatero Osorio, M. R.; Schöfer, P.; Lillo-Box, J.; Oshagh, M.;
   González-Álvarez, E.; Amado, P. J.; Barrado, D.; Béjar, V. J. S.;
   Cale, B.; Chaturvedi, P.; Cifuentes, C.; Cochran, W. D.; Collins,
   K. A.; Collins, K. I.; Cortés-Contreras, M.; Díez Alonso, E.; El
   Mufti, M.; Ercolino, A.; Fridlund, M.; Gaidos, E.; García, R. A.;
   Georgieva, I.; González-Cuesta, L.; Guerra, P.; Hatzes, A. P.;
   Henning, Th.; Herrero, E.; Hidalgo, D.; Isopi, G.; Jeffers, S. V.;
   Jenkins, J. M.; Jensen, E. L. N.; Kábath, P.; Kaminski, A.; Kemmer,
   J.; Korth, J.; Kossakowski, D.; Kürster, M.; Lafarga, M.; Mallia,
   F.; Montes, D.; Morales, J. C.; Morales-Calderón, M.; Murgas, F.;
   Narita, N.; Passegger, V. M.; Pedraz, S.; Persson, C. M.; Plavchan,
   P.; Rauer, H.; Redfield, S.; Reffert, S.; Reiners, A.; Ribas, I.;
   Ricker, G. R.; Rodríguez-López, C.; Santos, A. R. G.; Seager, S.;
   Schlecker, M.; Schweitzer, A.; Shan, Y.; Soto, M. G.; Subjak, J.;
   Tal-Or, L.; Trifonov, T.; Vanaverbeke, S.; Vanderspek, R.; Wittrock,
   J.; Zechmeister, M.; Zohrabi, F.
Bibcode: 2020A&A...639A.132B
Altcode: 2020arXiv200406218B
  We report the confirmation of a transiting planet around the bright
  weakly active M0.5 V star TOI-1235 (TYC 4384-1735-1, V ≈ 11.5 mag),
  whose transit signal was detected in the photometric time series
  of sectors 14, 20, and 21 of the TESS space mission. We confirm the
  planetary nature of the transit signal, which has a period of 3.44
  d, by using precise RV measurements with the CARMENES, HARPS-N,
  and iSHELL spectrographs, supplemented by high-resolution imaging
  and ground-based photometry. A comparison of the properties derived
  for TOI-1235 b with theoretical models reveals that the planet has
  a rocky composition, with a bulk density slightly higher than that
  of Earth. In particular, we measure a mass of M<SUB>p</SUB> = 5.9
  ± 0.6 M<SUB>⊕</SUB> and a radius of R<SUB>p</SUB> = 1.69 ± 0.08
  R<SUB>⊕</SUB>, which together result in a density of ρ<SUB>p</SUB>
  = 6.7<SUB>- 1.1</SUB><SUP>+ 1.3</SUP> g cm<SUP>-3</SUP>. When compared
  with other well-characterized exoplanetary systems, the particular
  combination of planetary radius and mass places our discovery in the
  radius gap, which is a transition region between rocky planets and
  planets with significant atmospheric envelopes. A few examples of
  planets occupying the radius gap are known to date. While the exact
  location of the radius gap for M dwarfs is still a matter of debate,
  our results constrain it to be located at around 1.7 R<SUB>⊕</SUB>
  or larger at the insolation levels received by TOI-1235 b (~60
  S<SUB>⊕</SUB>). This makes it an extremely interesting object for
  further studies of planet formation and atmospheric evolution.

Title: The CARMENES search for exoplanets around M dwarfs. Dynamical
    characterization of the multiple planet system GJ 1148 and prospects
    of habitable exomoons around GJ 1148 b
Authors: Trifonov, T.; Lee, M. H.; Kürster, M.; Henning, Th.; Grishin,
   E.; Stock, S.; Tjoa, J.; Caballero, J. A.; Wong, K. H.; Bauer, F. F.;
   Quirrenbach, A.; Zechmeister, M.; Ribas, I.; Reffert, S.; Reiners,
   A.; Amado, P. J.; Kossakowski, D.; Azzaro, M.; Béjar, V. J. S.;
   Cortés-Contreras, M.; Dreizler, S.; Hatzes, A. P.; Jeffers, S. V.;
   Kaminski, A.; Lafarga, M.; Montes, D.; Morales, J. C.; Pavlov, A.;
   Rodríguez-López, C.; Schmitt, J. H. M. M.; Solano, E.; Barnes, R.
Bibcode: 2020A&A...638A..16T
Altcode: 2020arXiv200200906T
  Context. GJ 1148 is an M-dwarf star hosting a planetary system composed
  of two Saturn-mass planets in eccentric orbits with periods of 41.38
  and 532.02 days. <BR /> Aims: We reanalyze the orbital configuration
  and dynamics of the GJ 1148 multi-planetary system based on new precise
  radial velocity measurements taken with CARMENES. <BR /> Methods: We
  combined new and archival precise Doppler measurements from CARMENES
  with those available from HIRES for GJ 1148 and modeled these data
  with a self-consistent dynamical model. We studied the orbital
  dynamics of the system using the secular theory and direct N-body
  integrations. The prospects of potentially habitable moons around GJ
  1148 b were examined. <BR /> Results: The refined dynamical analyses
  show that the GJ 1148 system is long-term stable in a large phase-space
  of orbital parameters with an orbital configuration suggesting apsidal
  alignment, but not in any particular high-order mean-motion resonant
  commensurability. GJ 1148 b orbits inside the optimistic habitable zone
  (HZ). We find only a narrow stability region around the planet where
  exomoons can exist. However, in this stable region exomoons exhibit
  quick orbital decay due to tidal interaction with the planet. <BR />
  Conclusions: The GJ 1148 planetary system is a very rare M-dwarf
  planetary system consisting of a pair of gas giants, the inner of
  which resides in the HZ. We conclude that habitable exomoons around
  GJ 1148 b are very unlikely to exist.

Title: VizieR Online Data Catalog: M dwarfs HeI infrared triplet
    variability (Fuhrmeister+, 2020)
Authors: Fuhrmeister, B.; Czesla, S.; Hildebrandt, L.; Nagel, E.;
   Schmitt, J. H. M. M.; Jeffers, S. V.; Caballero, J. A.; Hintz, D.;
   Johnson, E. N.; Schoefer, P.; Zechmeister, M.; Reiners, A.; Ribas,
   I.; Amado, P. J.; Quirrenbach, A.; Nortmann, L.; Bauer, F. F.; Bejar,
   V. J. S.; Cortes-Contreras, M.; Dreizler, S.; Galadi-Enriquez, D.;
   Hatzes, A. P.; Kaminski, A.; Kuerster, M.; Lafarga, M.; Montes, D.
Bibcode: 2020yCat..36400052F
Altcode:
  The HeI infrared (IR) triplet at 10830Å is known as an activity
  indicator and has become a primary diagnostic in exoplanetary
  transmission spectroscopy. The HeI IR lines are a tracer of the
  stellar extreme-ultraviolet irradiation from the transition region
  and corona. We study the variability of the HeI IR triplet lines in
  spectral time series of 319 M dwarf stars, obtained with the CARMENES
  spectrograph. <P />We measure the pseudo-equivalent width (pEW) in each
  stellar spectrum. The integration ranges for the line and the reference
  bands are found in Table 1 of the paper. For comparison purposes
  we also measure pEW values of Hα, the bluest CaII IR triplet line,
  and the HeI D<SUB>3</SUB> line. From these measurements we compute the
  mean pEW, the median absolute deviation (MAD) and Pearson's correlation
  coefficients for the lines. <P />(1 data file).

Title: A multiplanet system of super-Earths orbiting the brightest
    red dwarf star GJ 887
Authors: Jeffers, S. V.; Dreizler, S.; Barnes, J. R.; Haswell, C. A.;
   Nelson, R. P.; Rodríguez, E.; López-Gonz‧lez, M. J.; Morales, N.;
   Luque, R.; Zechmeister, M.; Vogt, S. S.; Jenkins, J. S.; Palle, E.;
   Berdi ñas, Z. M.; Coleman, G. A. L.; Díaz, M. R.; Ribas, I.; Jones,
   H. R. A.; Butler, R. P.; Tinney, C. G.; Bailey, J.; Carter, B. D.;
   O'Toole, S.; Wittenmyer, R. A.; Crane, J. D.; Feng, F.; Shectman,
   S. A.; Teske, J.; Reiners, A.; Amado, P. J.; Anglada-Escudé, G.
Bibcode: 2020Sci...368.1477J
Altcode: 2020arXiv200616372J
  The closet exoplanets to the Sun provide opportunities for detailed
  characterization of planets outside the Solar System. We report
  the discovery, using radial velocity measurements, of a compact
  multiplanet system of super-Earth exoplanets orbiting the nearby red
  dwarf star GJ 887. The two planets have orbital periods of 9.3 and
  21.8 days. Assuming an Earth-like albedo, the equilibrium temperature
  of the 21.8-day planet is ~350 kelvin. The planets are interior to,
  but close to the inner edge of, the liquid-water habitable zone. We
  also detect an unconfirmed signal with a period of ~50 days, which
  could correspond to a third super-Earth in a more temperate orbit. Our
  observations show that GJ 887 has photometric variability below 500
  parts per million, which is unusually quiet for a red dwarf.

Title: The CARMENES search for exoplanets around M dwarfs. The He
    I infrared triplet lines in PHOENIX models of M 2-3 V stars
Authors: Hintz, D.; Fuhrmeister, B.; Czesla, S.; Schmitt,
   J. H. M. M.; Schweitzer, A.; Nagel, E.; Johnson, E. N.; Caballero,
   J. A.; Zechmeister, M.; Jeffers, S. V.; Reiners, A.; Ribas, I.; Amado,
   P. J.; Quirrenbach, A.; Anglada-Escudé, G.; Bauer, F. F.; Béjar,
   V. J. S.; Cortés-Contreras, M.; Dreizler, S.; Galadí-Enríquez,
   D.; Guenther, E. W.; Hauschildt, P. H.; Kaminski, A.; Kürster, M.;
   Lafarga, M.; López del Fresno, M.; Montes, D.; Morales, J. C.
Bibcode: 2020A&A...638A.115H
Altcode: 2020arXiv200506246H
  The He I infrared (IR) line at a vacuum wavelength of 10 833 Å is a
  diagnostic for the investigation of atmospheres of stars and planets
  orbiting them. For the first time, we study the behavior of the He I
  IR line in a set of chromospheric models for M-dwarf stars, whose much
  denser chromospheres may favor collisions for the level population over
  photoionization and recombination, which are believed to be dominant
  in solar-type stars. For this purpose, we use published PHOENIX
  models for stars of spectral types M2 V and M3 V and also compute new
  series of models with different levels of activity following an ansatz
  developed for the case of the Sun. We perform a detailed analysis of
  the behavior of the He I IR line within these models. We evaluate the
  line in relation to other chromospheric lines and also the influence
  of the extreme ultraviolet (EUV) radiation field. The analysis of the
  He I IR line strengths as a function of the respective EUV radiation
  field strengths suggests that the mechanism of photoionization and
  recombination is necessary to form the line for inactive models, while
  collisions start to play a role in our most active models. Moreover,
  the published model set, which is optimized in the ranges of the Na
  I D<SUB>2</SUB>, Hα, and the bluest Ca II IR triplet line, gives an
  adequate prediction of the He I IR line for most stars of the stellar
  sample. Because especially the most inactive stars with weak He I IR
  lines are fit worst by our models, it seems that our assumption of
  a 100% filling factor of a single inactive component no longer holds
  for these stars.

Title: The CARMENES search for exoplanets around M dwarfs. A
    super-Earth planet orbiting HD 79211 (GJ 338 B)
Authors: González-Álvarez, E.; Zapatero Osorio, M. R.; Caballero,
   J. A.; Sanz-Forcada, J.; Béjar, V. J. S.; González-Cuesta, L.;
   Dreizler, S.; Bauer, F. F.; Rodríguez, E.; Tal-Or, L.; Zechmeister,
   M.; Montes, D.; López-González, M. J.; Ribas, I.; Reiners, A.;
   Quirrenbach, A.; Amado, P. J.; Anglada-Escudé, G.; Azzaro, M.;
   Cortés-Contreras, M.; Hatzes, A. P.; Henning, T.; Jeffers, S. V.;
   Kaminski, A.; Kürster, M.; Lafarga, M.; Morales, J. C.; Pallé, E.;
   Perger, M.; Schmitt, J. H. M. M.
Bibcode: 2020A&A...637A..93G
Altcode: 2020arXiv200313052G
  <BR /> Aims: We report on radial velocity time series for two M0.0
  V stars, GJ 338 B and GJ 338 A, using the CARMENES spectrograph,
  complemented by ground-telescope photometry from Las Cumbres and
  Sierra Nevada observatories. We aim to explore the presence of small
  planets in tight orbits using the spectroscopic radial velocity
  technique. <BR /> Methods: We obtained 159 and 70 radial velocity
  measurements of GJ 338 B and A, respectively, with the CARMENES
  visible channel between 2016 January and 2018 October. We also
  compiled additional relative radial velocity measurements from the
  literature and a collection of astrometric data that cover 200 a of
  observations to solve for the binary orbit. <BR /> Results: We found
  dynamical masses of 0.64 ± 0.07 M<SUB>⊙</SUB> for GJ 338 B and 0.69
  ± 0.07 M<SUB>⊙</SUB> for GJ 338 A. The CARMENES radial velocity
  periodograms show significant peaks at 16.61 ± 0.04 d (GJ 338 B) and
  16.3<SUB>-1.3</SUB><SUP>+3.5</SUP> d (GJ 338 A), which have counterparts
  at the same frequencies in CARMENES activity indicators and photometric
  light curves. We attribute these to stellar rotation. GJ 338 B shows
  two additional, significant signals at 8.27 ± 0.01 and 24.45 ± 0.02
  d, with no obvious counterparts in the stellar activity indices. The
  former is likely the first harmonic of the star's rotation, while we
  ascribe the latter to the existence of a super-Earth planet with a
  minimum mass of 10.27<SUB>-1.38</SUB><SUP>+1.47</SUP> M<SUB>⊕</SUB>
  orbiting GJ 338 B. We have not detected signals of likely planetary
  origin around GJ 338 A. <BR /> Conclusions: GJ 338 Bb lies inside
  the inner boundary of the habitable zone around its parent star. It
  is one of the least massive planets ever found around any member
  of stellar binaries. The masses, spectral types, brightnesses,
  and even the rotational periods are very similar for both stars,
  which are likely coeval and formed from the same molecular cloud, yet
  they differ in the architecture of their planetary systems. <P />Full
  Tables B.1-B.6 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/637/A93">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/637/A93</A>

Title: The CARMENES search for exoplanets around M
    dwarfs. Characterization of the nearby ultra-compact multiplanetary
    system YZ Ceti
Authors: Stock, S.; Kemmer, J.; Reffert, S.; Trifonov, T.; Kaminski,
   A.; Dreizler, S.; Quirrenbach, A.; Caballero, J. A.; Reiners,
   A.; Jeffers, S. V.; Anglada-Escudé, G.; Ribas, I.; Amado, P. J.;
   Barrado, D.; Barnes, J. R.; Bauer, F. F.; Berdiñas, Z. M.; Béjar,
   V. J. S.; Coleman, G. A. L.; Cortés-Contreras, M.; Díez-Alonso, E.;
   Domínguez-Fernández, A. J.; Espinoza, N.; Haswell, C. A.; Hatzes,
   A.; Henning, T.; Jenkins, J. S.; Jones, H. R. A.; Kossakowski, D.;
   Kürster, M.; Lafarga, M.; Lee, M. H.; López González, M. J.; Montes,
   D.; Morales, J. C.; Morales, N.; Pallé, E.; Pedraz, S.; Rodríguez,
   E.; Rodríguez-López, C.; Zechmeister, M.
Bibcode: 2020A&A...636A.119S
Altcode: 2020arXiv200201772S
  Context. The nearby ultra-compact multiplanetary system YZ Ceti consists
  of at least three planets, and a fourth tentative signal. The orbital
  period of each planet is the subject of discussion in the literature
  due to strong aliasing in the radial velocity data. The stellar
  activity of this M dwarf also hampers significantly the derivation
  of the planetary parameters. <BR /> Aims: With an additional 229
  radial velocity measurements obtained since the discovery publication,
  we reanalyze the YZ Ceti system and resolve the alias issues. <BR />
  Methods: We use model comparison in the framework of Bayesian statistics
  and periodogram simulations based on a method by Dawson and Fabrycky
  to resolve the aliases. We discuss additional signals in the RV data,
  and derive the planetary parameters by simultaneously modeling the
  stellar activity with a Gaussian process regression model. To constrain
  the planetary parameters further we apply a stability analysis on our
  ensemble of Keplerian fits. <BR /> Results: We find no evidence for a
  fourth possible companion. We resolve the aliases: the three planets
  orbit the star with periods of 2.02 d, 3.06 d, and 4.66 d. We also
  investigate an effect of the stellar rotational signal on the derivation
  of the planetary parameters, in particular the eccentricity of the
  innermost planet. Using photometry we determine the stellar rotational
  period to be close to 68 d and we also detect this signal in the
  residuals of a three-planet fit to the RV data and the spectral activity
  indicators. From our stability analysis we derive a lower limit on the
  inclination of the system with the assumption of coplanar orbits which
  is i<SUB>min</SUB> = 0.9 deg. From the absence of a transit event with
  TESS, we derive an upper limit of the inclination of i<SUB>max</SUB> =
  87.43 deg. <BR /> Conclusions: YZ Ceti is a prime example of a system
  where strong aliasing hindered the determination of the orbital
  periods of exoplanets. Additionally, stellar activity influences
  the derivation of planetary parameters and modeling them correctly
  is important for the reliable estimation of the orbital parameters
  in this specific compact system. Stability considerations then allow
  additional constraints to be placed on the planetary parameters. <P
  />Table B.1 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/636/A119">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/636/A119</A>.

Title: The CARMENES search for exoplanets around M dwarfs. Radial
    velocities and activity indicators from cross-correlation functions
    with weighted binary masks
Authors: Lafarga, M.; Ribas, I.; Lovis, C.; Perger, M.; Zechmeister,
   M.; Bauer, F. F.; Kürster, M.; Cortés-Contreras, M.; Morales,
   J. C.; Herrero, E.; Rosich, A.; Baroch, D.; Reiners, A.; Caballero,
   J. A.; Quirrenbach, A.; Amado, P. J.; Alacid, J. M.; Béjar, V. J. S.;
   Dreizler, S.; Hatzes, A. P.; Henning, T.; Jeffers, S. V.; Kaminski,
   A.; Montes, D.; Pedraz, S.; Rodríguez-López, C.; Schmitt, J. H. M. M.
Bibcode: 2020A&A...636A..36L
Altcode: 2020arXiv200307471L
  Context. For years, the standard procedure to measure radial velocities
  (RVs) of spectral observations consisted in cross-correlating the
  spectra with a binary mask, that is, a simple stellar template that
  contains information on the position and strength of stellar absorption
  lines. The cross-correlation function (CCF) profiles also provide
  several indicators of stellar activity. <BR /> Aims: We present a
  methodology to first build weighted binary masks and, second, to
  compute the CCF of spectral observations with these masks from which
  we derive radial velocities and activity indicators. These methods
  are implemented in a python code that is publicly available. <BR />
  Methods: To build the masks, we selected a large number of sharp
  absorption lines based on the profile of the minima present in high
  signal-to-noise ratio (S/N) spectrum templates built from observations
  of reference stars. We computed the CCFs of observed spectra and
  derived RVs and the following three standard activity indicators:
  full-width-at-half-maximum as well as contrast and bisector inverse
  slope. <BR /> Results: We applied our methodology to CARMENES
  high-resolution spectra and obtain RV and activity indicator time
  series of more than 300 M dwarf stars observed for the main CARMENES
  survey. Compared with the standard CARMENES template matching pipeline,
  in general we obtain more precise RVs in the cases where the template
  used in the standard pipeline did not have enough S/N. We also show
  the behaviour of the three activity indicators for the active star YZ
  CMi and estimate the absolute RV of the M dwarfs analysed using the CCF
  RVs. <P />Table A.1 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/636/A36">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/636/A36</A>

Title: Power spectra of solar brightness variations at various
    inclinations
Authors: Nèmec, N. -E.; Shapiro, A. I.; Krivova, N. A.; Solanki,
   S. K.; Tagirov, R. V.; Cameron, R. H.; Dreizler, S.
Bibcode: 2020A&A...636A..43N
Altcode: 2020arXiv200210895N
  Context. Magnetic features on the surfaces of cool stars lead to
  variations in their brightness. Such variations on the surface of
  the Sun have been studied extensively. Recent planet-hunting space
  telescopes have made it possible to measure brightness variations
  in hundred thousands of other stars. The new data may undermine
  the validity of setting the sun as a typical example of a variable
  star. Putting solar variability into the stellar context suffers,
  however, from a bias resulting from solar observations being carried
  out from its near-equatorial plane, whereas stars are generally
  observed at all possible inclinations. <BR /> Aims: We model solar
  brightness variations at timescales from days to years as they would
  be observed at different inclinations. In particular, we consider the
  effect of the inclination on the power spectrum of solar brightness
  variations. The variations are calculated in several passbands that are
  routinely used for stellar measurements. <BR /> Methods: We employ the
  surface flux transport model to simulate the time-dependent spatial
  distribution of magnetic features on both the near and far sides of
  the Sun. This distribution is then used to calculate solar brightness
  variations following the Spectral And Total Irradiance REconstruction
  approach. <BR /> Results: We have quantified the effect of the
  inclination on solar brightness variability at timescales down to a
  single day. Thus, our results allow for solar brightness records to
  be made directly comparable to those obtained by planet-hunting space
  telescopes. Furthermore, we decompose solar brightness variations into
  components originating from the solar rotation and from the evolution
  of magnetic features.

Title: VizieR Online Data Catalog: Absolute radial velocities of
    CARMENES M dwarfs (Lafarga+, 2020)
Authors: Lafarga, M.; Ribas, I.; Lovis, C.; Perger, M.; Zechmeister,
   M.; Bauer, F. F.; Kuerster, M.; Cortes-Contreras, M.; Morales,
   J. C.; Herrero, E.; Rosich, A.; Baroch, D.; Reiners, A.; Caballero,
   J. A.; Quirrenbach, A.; Amado, P. J.; Alacid, J. M.; Bejar, V. J. S.;
   Dreizler, S.; Hatzes, A. P.; Henning, T.; Jeffers, S. V.; Kaminski,
   A.; Montes, D.; Pedraz, S.; Rodriguez-Lopez, C.; Schmitt, J. H. M. M.
Bibcode: 2020yCat..36360036L
Altcode:
  Absolute radial velocities (RVs) of 323 M dwarf stars observed with
  CARMENES. The RVs were computed using the cross-correlation function
  (CCF) method with binary masks on CARMENES visual observations. The
  RV values and uncertainties also take into account the gravitational
  redshift and the convective blueshift of the stars. The gravitational
  redshift is computed using mass and radius values from Schweitzer
  et al., 2019A&amp;A...625A..68S, Cat. J/A+A/625/A68. We consider the
  convective blueshift to be 0+/-100m/s for all stars. <P />(1 data file).

Title: VizieR Online Data Catalog: HD 79211 CARMENES radial velocities
    (Gonzalez-Alvarez+, 2020)
Authors: Gonzalez-Alvarez, E.; Zapatero Osorio, M. R.; Caballero,
   J. A.; Sanz-Forcada, J.; Bejar, V. J. S.; Gonzalez-Cuesta, L.;
   Dreizler, S.; Bauer, F. F.; Rodriguez, E.; Tal-Or, L.; Zechmeister, M.;
   Montes, D.; Lopez-Gonzalez, M. J.; Ribas, I.; Reiners, A.; Quirrenbach,
   A.; Amado, P. J.; Anglada-Escude, G.; Azzaro, M.; Cortes-Contreras, M.;
   Hatzes, A. P.; Henning, T.; Jeffers, S. V.; Kaminski, A.; Kuerster,
   M.; Lafarga, M.; Morales, J. C.; Palle, E.; Perger, M.; Schmitt,
   J. H. M. M.
Bibcode: 2020yCat..36370093G
Altcode:
  Detailed CARMENES RV analysis of the M0.0 V stars GJ 338 A (HD 79210)
  and GJ 338 B (HD 79211), a wide binary system with similar mass stellar
  components. <P />New RVs were obtained for each member of the stellar
  binary using the CARMENES fibre-fed, echelle spectrograph. CARMENES
  is installed at the 3.5m telescope of the Calar Alto Observatory in
  Almeria (Spain). <P />(6 data files).

Title: Stellar activity consequence on the retrieved transmission
    spectra through chromatic Rossiter-McLaughlin observations
Authors: Boldt, S.; Oshagh, M.; Dreizler, S.; Mallonn, M.; Santos,
   N. C.; Claret, A.; Reiners, A.; Sedaghati, E.
Bibcode: 2020A&A...635A.123B
Altcode: 2020arXiv200206373B
  Mostly multiband photometric transit observations have been used so far
  to retrieve broadband transmission spectra of transiting exoplanets
  in order to study their atmosphere. An alternative method has been
  proposed and has only been used once to recover transmission spectra
  using chromatic Rossiter-McLaughlin observations. Stellar activity has
  been shown to potentially imitate narrow and broadband features in the
  transmission spectra retrieved from multiband photometric observations;
  however, there has been no study regarding the influence of stellar
  activity on the retrieved transmission spectra through chromatic
  Rossiter-McLaughlin. In this study with the modified SOAP3.0 tool,
  we consider different types of stellar activity features (spots and
  plages), and we generated a large number of realistic chromatic
  Rossiter-McLaughlin curves for different types of planets and
  stars. We were then able to retrieve their transmission spectra
  to evaluate the impact of stellar activity on them. We find that
  chromatic Rossiter-McLaughlin observations are also not immune to
  stellar activity, which can mimic broadband features, such as Rayleigh
  scattering slope, in their retrieved transmission spectra. We also
  find that the influence is independent of the planet radius, orbital
  orientations, orbital period, and stellar rotation rate. However,
  more general simulations demonstrate that the probability of mimicking
  strong broadband features is lower than 25% and that can be mitigated
  by combining several Rossiter-McLaughlin observations obtained during
  several transits.

Title: The binary content of multiple populations in NGC 3201
Authors: Kamann, S.; Giesers, B.; Bastian, N.; Brinchmann, J.;
   Dreizler, S.; Göttgens, F.; Husser, T. -O.; Latour, M.; Weilbacher,
   P. M.; Wisotzki, L.
Bibcode: 2020A&A...635A..65K
Altcode: 2019arXiv191201627K
  We investigate the binary content of the two stellar populations that
  coexist in the globular cluster NGC 3201. Previous studies of binary
  stars in globular clusters have reported higher binary fractions in
  their first populations (P1, having field-like abundances) compared
  to their second populations (P2, having anomalous abundances). This
  is interpreted as evidence for the latter forming more centrally
  concentrated. In contrast to previous studies, our analysis focusses
  on the cluster centre, where comparable binary fractions between the
  populations are predicted because of short relaxation times. However,
  we find that even in the centre of NGC 3201, the observed binary
  fraction of P1 is higher (23.1 ± 6.2)% compared to (8.2 ± 3.5)%
  in P2. Our results are difficult to reconcile with a scenario in
  which the populations only differ in their initial concentrations,
  but instead suggests that the populations also formed with different
  fractions of binary stars.

Title: The MUSE-Faint survey. I. Spectroscopic evidence for a star
    cluster in Eridanus 2 and constraints on MACHOs as a constituent of
    dark matter
Authors: Zoutendijk, Sebastiaan L.; Brinchmann, Jarle; Boogaard,
   Leindert A.; Gunawardhana, Madusha L. P.; Husser, Tim-Oliver; Kamann,
   Sebastian; Ramos Padilla, Andrés Felipe; Roth, Martin M.; Bacon,
   Roland; den Brok, Mark; Dreizler, Stefan; Krajnović, Davor
Bibcode: 2020A&A...635A.107Z
Altcode: 2020arXiv200108790Z
  <BR /> Aims: It has been shown that the ultra-faint dwarf galaxy
  Eridanus 2 may host a stellar cluster in its centre. If this cluster
  is shown to exist, it can be used to set constraints on the mass and
  abundance of massive astrophysical compact halo objects (MACHOs) as a
  form of dark matter. Previous research has shown promising expectations
  in the mass range of 10-100 M<SUB>⊙</SUB>, but lacked spectroscopic
  measurements of the cluster. We aim to provide spectroscopic evidence
  regarding the nature of the putative star cluster in Eridanus 2 and to
  place constraints on MACHOs as a constituent of dark matter. <BR />
  Methods: We present spectroscopic observations of the central square
  arcminute of Eridanus 2 from MUSE-Faint, a survey of ultra-faint dwarf
  galaxies with the Multi Unit Spectroscopic Explorer on the Very Large
  Telescope. We derived line-of-sight velocities for possible member stars
  of the putative cluster and for stars in the centre of Eridanus 2. We
  discuss the existence of the cluster and determine new constraints for
  MACHOs using the Fokker-Planck diffusion approximation. <BR /> Results:
  Out of 182 extracted spectra, we identify 26 member stars of Eridanus
  2, seven of which are possible cluster members. We find intrinsic
  mean line-of-sight velocities of 79.7<SUP>+3.1</SUP><SUB>-3.8</SUB> km
  s<SUP>-1</SUP> and 76.0<SUP>+3.2</SUP><SUB>-3.7</SUB> km s<SUP>-1</SUP>
  for the cluster and the bulk of Eridanus 2, respectively, as well
  as intrinsic velocity dispersions of &lt; 7.6 km s<SUP>-1</SUP>
  (68% upper limit) and 10.3<SUP>+3.9</SUP><SUB>-3.2</SUB> km
  s<SUP>-1</SUP>, respectively. This indicates that the cluster most
  likely exists as a distinct dynamical population hosted by Eridanus 2
  and that it does not have a surplus of dark matter over the background
  distribution. Among the member stars in the bulk of Eridanus 2, we find
  possible carbon stars, alluding to the existence of an intermediate-age
  population. We derived constraints on the fraction of dark matter that
  can consist of MACHOs with a given mass between 1 and 10<SUP>5</SUP>
  M<SUB>⊙</SUB>. For dark matter consisting purely of MACHOs, the
  mass of the MACHOs must be less than ∼7.6 M<SUB>⊙</SUB> and ∼44
  M<SUB>⊙</SUB> at a 68- and 95% confidence level, respectively. <P
  />Table 2 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/635/A107">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/635/A107</A>
  <P />Based on observations made with ESO Telescopes at the La Silla
  Paranal Observatory under programme ID 0100.D-0807.

Title: A stellar census in globular clusters with MUSE. Extending
    the CaT-metallicity relation below the horizontal branch and applying
    it to multiple populations
Authors: Husser, Tim-Oliver; Latour, Marilyn; Brinchmann, Jarle;
   Dreizler, Stefan; Giesers, Benjamin; Göttgens, Fabian; Kamann,
   Sebastian; Roth, Martin M.; Weilbacher, Peter M.; Wendt, Martin
Bibcode: 2020A&A...635A.114H
Altcode: 2020arXiv200107725H
  <BR /> Aims: We use the spectra of more than 30 000 red giant branch
  (RGB) stars in 25 globular clusters (GC), obtained within the MUSE
  survey of Galactic globular clusters, to calibrate the Ca II triplet
  metallicity relation and derive metallicities for all individual
  stars. We investigate the overall metallicity distributions as well
  as those of the different populations within each cluster. <BR />
  Methods: The Ca II triplet in the near-infrared at 8498, 8542, and 8662
  Å is visible in stars with spectral types between F and M and can
  be used to determine their metallicities. In this work, we calibrate
  the relation using average cluster metallicities from literature and
  MUSE spectra, and extend it below the horizontal branch - a cutoff
  that has traditionally been made to avoid a non-linear relation -
  using a quadratic function. In addition to the classic relation
  based on V - V<SUB>HB</SUB>, we also present calibrations based on
  absolute magnitude and luminosity. The obtained relations were used to
  calculate metallicities for all the stars in the sample and to derive
  metallicity distributions for different populations within a cluster,
  which have been separated using so-called "chromosome maps" based on
  HST photometry. <BR /> Results: We show that despite the relatively
  low spectral resolution of MUSE (R = 1900 - 3700) we can derive single
  star metallicities with a mean statistical intra-cluster uncertainty of
  ∼0.12 dex. We present metallicity distributions for the RGB stars in
  25 GCs and investigate the different metallicities of the populations P3
  (and higher) in so-called metal-complex or Type II clusters, finding
  metallicity variations in all of them. We also detected unexpected
  metallicity variations in the Type I cluster <ASTROBJ>NGC 2808</ASTROBJ>
  and confirm the Type II status of <ASTROBJ>NGC 7078</ASTROBJ>. <P
  />Table 8 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/635/A114">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/635/A114</A>

Title: VizieR Online Data Catalog: GJ 3512 radial velocity and light
    curves (Morales+, 2019)
Authors: Morales, J. C.; Mustill, A. J.; Ribas, I.; Davies, M. B.;
   Reiners, A.; Bauer, F. F.; Kossakowski, D.; Herrero, E.; Rodriguez,
   E.; Lopez-Gonzalez, M. J.; Rodriguez-Lopez, C.; Bejar, V. J. S.;
   Gonzalez-Cuesta, L.; Luque, R.; Palle, E.; Perger, M.; Baroch,
   D.; Johansen, A.; Klahr, H.; Mordasini, C.; Anglada-Escude, G.;
   Caballero, J. A.; Cortes-Contreras, M.; Dreizler, S.; Lafarga, M.;
   Nagel, E.; Passegger, V. M.; Reffert, S.; Rosich, A.; Schweitzer,
   A.; Tal-Or, L.; Trifonov, T.; Zechmeister, M.; Quirrenbach, A.;
   Amado, P. J.; Guenther, E. W.; Hagen, H. -J.; Henning, T.; Jeffers,
   S. V.; Kaminski, A.; Kurster, M.; Montes, D.; Seifert, W.; Abellan,
   F. J.; Abril, M.; Aceituno, J.; Aceituno, F. J.; Alonso-Floriano,
   F. J.; Ammler-von Eiff, M.; Antona, R.; Arroyo-Torres, B.; Azzaro,
   M.; Barrado, D.; Becerril-Jarque, S.; Benitez, D.; Berdinas, Z. M.;
   Bergond, G.; Brinkmoller, M.; Del Burgo, C.; Burn, R.; Calvo-Ortega,
   R.; Cano, J.; Cardenas, M. C.; Cardona Guillen, C.; Carro, J.; Casal,
   E.; Casanova, V.; Casasayas-Barris, N.; Chaturvedi, P.; Cifuentes,
   C.; Claret, A.; Colome, J.; Czesla, S.; Diez-Alonso, E.; Dorda, R.;
   Emsenhuber, A.; Fernandez, M.; Fernandez-Martin, A.; Ferro, I. M.;
   Fuhrmeister, B.; Galadi-Enriquez, D.; Gallardo Cava, I.; Garcia Vargas,
   M. L.; Garcia-Piquer, A.; Gesa, L.; Gonzalez-Alvarez, E.; Gonzalez
   Hernandez, J. I.; Gonzalez-Peinado, R.; Guardia, J.; Guijarro, A.;
   de Guindos, E.; Hatzes, A. P.; Hauschildt, P. H.; Hedrosa, R. P.;
   Hermelo, I.; Hernandez Arabi, R.; Hernandez, Otero F.; Hintz, D.;
   Holgado, G.; Huber, A.; Huke, P.; Johnson, E. N.; de Juan, E.; Kehr,
   M.; Kemmer, J.; Kim, M.; Kluter, J.; Klutsch, A.; Labarga, F.; Labiche,
   N.; Lalitha, S.; Lampon, M.; Lara, L. M.; Launhardt, R.; Lazaro,
   F. J.; Lizon, J. -L.; Llamas, M.; Lodieu, N.; Lopez Del Fresno, M.;
   Lopez Salas, J. F.; Lopez-Santiago, J.; Magan Madinabeitia, H.; Mall,
   U.; Mancini, L.; Mandel, H.; Marfil, E.; Marin Molina, J. A.; Martin,
   E. L.; Martin-Fernandez, P.; Martin-Ruiz, S.; Martinez-Rodriguez,
   H.; Marvin, C. J.; Mirabet, E.; Moya, A.; Naranjo, V.; Nelson, R. P.;
   Nortmann, L.; Nowak, G.; Ofir, A.; Pascual, J.; Pavlov, A.; Pedraz,
   S.; Perez Medialde, A. D.; Perez-Calpena, A.; Perryman, M. A. C.;
   Rabaza, O.; Ramon Ballesta, A.; Rebolo, R.; Redondo, P.; Rix, H. -W.;
   Rodler, F.; Rodriguez Trinidad, A.; Sabotta, S.; Sadegi, S.; Salz,
   M.; Sanchez-Blanco, E.; Sanchez Carrasco, M. A.; Sanchez-Lopez, A.;
   Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schafer, S.; Schlecker,
   M.; Schmitt, J. H. M. M.; Schofer, P.; Solano, E.; Sota, A.; Stahl, O.;
   Stock, S.; Stuber, T.; Sturmer, J.; Suarez, J. C.; Tabernero, H. M.;
   Tulloch, S. M.; Veredas, G.; Vico-Linares, J. I.; Vilardell, F.;
   Wagner, K.; Winkler, J.; Wolthoff, V.; Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2020yCatp021036502M
Altcode:
  These tables list the radial velocities measured with the
  visual (VIS) and near-infrared (NIR) channels of the CARMENES
  spectrograph (Quirrenbach et al. 2018SPIE10702E..0WQ), and the
  stellar activity indices computed with SERVAL (Zechmeister et
  al. 2018A&amp;A...609A..12Z). Photometry obtained from the Montsec,
  Sierra Nevada, and las Cumbres observatories is also listed here as
  used in the paper. <P />(4 data files).

Title: RedDots: a temperate 1.5 Earth-mass planet candidate in a
    compact multiterrestrial planet system around GJ 1061
Authors: Dreizler, S.; Jeffers, S. V.; Rodríguez, E.; Zechmeister, M.;
   Barnes, J. R.; Haswell, C. A.; Coleman, G. A. L.; Lalitha, S.; Hidalgo
   Soto, D.; Strachan, J. B. P.; Hambsch, F. -J.; López-González,
   M. J.; Morales, N.; Rodríguez López, C.; Berdiñas, Z. M.; Ribas,
   I.; Pallé, E.; Reiners, A.; Anglada-Escudé, G.
Bibcode: 2020MNRAS.493..536D
Altcode: 2019arXiv190804717D; 2020MNRAS.tmp..235D
  Small low-mass stars are favourable targets for the detection
  of rocky habitable planets. In particular, planetary systems in
  the solar neighbourhood are interesting and suitable for precise
  characterization. The RedDots campaigns seek to discover rocky planets
  orbiting nearby low-mass stars. The 2018 campaign targeted GJ 1061,
  which is the 20th nearest star to the Sun. For three consecutive months
  we obtained nightly, high-precision radial velocity measurements with
  the HARPS spectrograph. We analysed these data together with archival
  HARPS data. We report the detection of three planet candidates with
  periods of 3.204 ± 0.001, 6.689 ± 0.005, and 13.03 ± 0.03 d,
  which are close to 1:2:4 period commensurability. After several
  considerations related to the properties of the noise and sampling,
  we conclude that a fourth signal is most likely explained by stellar
  rotation, although it may be due to a planet. The proposed three-planet
  system (and the potential four-planet solution) is long-term dynamically
  stable. Planet-planet gravitational interactions are below our current
  detection threshold. The minimum masses of the three planets range from
  1.4 ± 0.2 to 1.8 ± 0.3 M<SUB>⊕</SUB>. Planet d, with msin I = 1.64
  ± 0.24 M<SUB>⊕</SUB>, receives a similar amount of energy as Earth
  receives from the Sun. Consequently it lies within the liquid-water
  habitable zone of the star and has a similar equilibrium temperature
  to Earth. GJ 1061 has very similar properties to Proxima Centauri but
  activity indices point to lower levels of stellar activity.

Title: The peculiar kinematics of the multiple populations in the
    globular cluster Messier 80 (NGC 6093)
Authors: Kamann, S.; Dalessandro, E.; Bastian, N.; Brinchmann, J.;
   den Brok, M.; Dreizler, S.; Giesers, B.; Göttgens, F.; Husser,
   T. -O.; Krajnović, D.; van de Ven, G.; Watkins, L. L.; Wisotzki, L.
Bibcode: 2020MNRAS.492..966K
Altcode: 2019arXiv191206158K; 2019MNRAS.tmp.3140K
  We combine MUSE spectroscopy and Hubble Space Telescope ultraviolet
  (UV) photometry to perform a study of the chemistry and dynamics of the
  Galactic globular cluster Messier 80 (M80, NGC 6093). Previous studies
  have revealed three stellar populations that vary not only in their
  light-element abundances, but also in their radial distributions, with
  the concentration decreasing with increasing nitrogen enrichment. This
  remarkable trend, which sets M80 apart from other Galactic globular
  clusters, points towards a complex formation and evolutionary
  history. To better understand how M80 formed and evolved, revealing its
  internal kinematics is key. We find that the most N-enriched population
  rotates faster than the other two populations at a 2σ confidence
  level. While our data further suggest that the intermediate population
  shows the least amount of rotation, this trend is rather marginal
  (1-2σ). Using axisymmetric Jeans models, we show that these findings
  can be explained from the radial distributions of the populations if
  they possess different angular momenta. Our findings suggest that the
  populations formed with primordial kinematical differences.

Title: The CARMENES search for exoplanets around M
    dwarfs. Photospheric parameters of target stars from high-resolution
    spectroscopy. II. Simultaneous multi-wavelength range modeling of
    activity insensitive lines (Corrigendum)
Authors: Passegger, V. M.; Schweitzer, A.; Shulyak, D.; Nagel, E.;
   Hauschildt, P. H.; Reiners, A.; Amado, P. J.; Caballero, J. A.;
   Cortés-Contreras, M.; Domínguez-Fernández, A. J.; Quirrenbach,
   A.; Ribas, I.; Azzaro, M.; Anglada-Escudé, G.; Bauer, F. F.; Béjar,
   V. J. S.; Dreizler, S.; Guenther, E. W.; Henning, T.; Jeffers, S. V.;
   Kaminski, A.; Kürster, M.; Lafarga, M.; Martín, E. L.; Montes, D.;
   Morales, J. C.; Schmitt, J. H. M. M.; Zechmeister, M.
Bibcode: 2020A&A...634C...2P
Altcode:
  No abstract at ADS

Title: VizieR Online Data Catalog: EW and [Fe/H] for 30000 globular
    cluster RGB stars (Husser+ 2020)
Authors: Husser, T. -O.; Latour, M.; Brinchmann, J.; Dreizler, S.;
   Giesers, B.; Goettgens, F.; Kamann, S.; Roth, M. M.; Weilbacher,
   P. M.; Wendt, M.
Bibcode: 2020yCat..36350114H
Altcode:
  We measured equivalent widths of &gt;30000 red giant branch stars in
  25 globular clusters from our large MUSE survey and used mean cluster
  metallicities to calibrate the CaT-metallicity relation, from which
  reduced equivalent widths and metallicities were calculated for all
  stars. Metallicities are given for four different calibrations,
  based on the classical linear relation with only stars brighter
  than the HB (1), all RGB stars and a quadratic relation (2), and
  two calibrations based on absolute magnitude (3) and luminosity
  (4). All metallicities are derived on the scale defined by Dias
  et al. (2016A&amp;A...590A...9D). The star IDs are taken from
  the ACS Survey of Galactic Globular Clusters (Anderson et al.,
  2008AJ....135.2055A), if they exist in that catalog. <P />(1 data file).

Title: VizieR Online Data Catalog: Spectroscopy of the Eri 2 cluster
    (Zoutendijk+, 2020)
Authors: Zoutendijk, S. L.; Brinchmann, J.; Boogaard, L. A.;
   Gunawardhana, M. L. P.; Husser, T. -O.; Kamann, S.; Ramos Padilla,
   A. F.; Roth, M. M.; Bacon, R.; den Brok, M.; Dreizler, S.; Krajnovic,
   K.
Bibcode: 2020yCat..36350107Z
Altcode:
  This table contains sources observed with the Multi Unit Spectroscopic
  Explorer on the Very Large Telescope towards the centre of the
  ultra-faint dwarf galaxy Eridanus 2 and its possible stellar
  cluster. These measurements were used to determine the velocity
  distributions of the putative cluster and the bulk of Eridanus 2,
  to assess the nature of the cluster, and to derive constraints on
  massive astrophysical compact halo objects. The sources in this table
  were limited to those with a spectral signal to noise of at least 5,
  a spectrum not showing galactic emission lines, and a measurement
  of radial velocity; or those that we identified as potential carbon
  stars. The positions have been calibrated against GAIA DR2. <P />(1
  data file).

Title: VizieR Online Data Catalog: YZ Ceti CARMENES and HARPS radial
    velocity curve (Stock+, 2020)
Authors: Stock, S.; Kemmer, J.; Reffert, S.; Trifonov, T.; Kaminski,
   A.; Dreizler, S.; Quirrenbach, A.; Caballero, J. A.; Reiners,
   A.; Jeffers, S. V.; Anglada-Escude, G.; Ribas, I.; Amado, P. J.;
   Barrado, D.; Barnes, J. R.; Bauer, F. F.; Berdinas, Z. M.; Bejar,
   V. J. S.; Coleman, G. A. L.; Cortes-Contreras, M.; Diez-Alonso, E.;
   Dominguez-Fernandez, A. J.; Espinoza, N.; Haswell, C. A.; Hatzes,
   A.; Henning, T.; Jenkins, J. S.; Jones, H. R. A.; Kossakowski, D.;
   Kuerster, M.; Lafarga, M.; Lee, M. H.; Lopez Gonzalez, M. J.; Montes,
   D.; Morales, J. C.; Morales, N.; Palle, E.; Pedraz, S.; Rodriguez,
   E.; Rodriguez-Lopez, C.; Zechmeister, M.
Bibcode: 2020yCat..36360119S
Altcode:
  We acquired spectra with CARMENES (Quirrenbach et al., 2014, in
  Proc. SPIE, Vol. 9147, Ground-based and Airborne Instrumentation for
  Astronomy V, 91471F), a high-resolution precise echelle spectrograph
  mounted at the 3.5m telescope at the Calar Alto Observatory in Spain. We
  combined this data with 334 high-resolution spectra from HARPS, of which
  59 were collected by the Red Dots program (Dreizler et al., 2019, arXiv
  e-prints, arXiv:1908.04717) and the remaining by Astudillo-Defru et
  al. (2017A&amp;A...605L..11A, Cat. J/A+A/605/L11). <P />(1 data file).

Title: A stellar census in globular clusters with MUSE: Binaries in
    NGC 3201
Authors: Giesers, Benjamin; Kamann, Sebastian; Dreizler, Stefan;
   Husser, Tim-Oliver; Askar, Abbas; Göttgens, Fabian; Brinchmann, Jarle;
   Latour, Marilyn; Weilbacher, Peter M.; Wendt, Martin; Roth, Martin M.
Bibcode: 2019A&A...632A...3G
Altcode: 2019arXiv190904050G
  We utilise multi-epoch MUSE spectroscopy to study binary stars in the
  core of the Galactic globular cluster NGC 3201. Our sample consists of
  3553 stars with 54 883 spectra in total comprising 3200 main-sequence
  stars up to 4 magnitudes below the turn-off. Each star in our sample
  has between 3 and 63 (with a median of 14) reliable radial velocity
  measurements within five years of observations. We introduce a
  statistical method to determine the probability of a star showing
  radial velocity variations based on the whole inhomogeneous radial
  velocity sample. Using HST photometry and an advanced dynamical MOCCA
  simulation of this specific cluster we overcome observational biases
  that previous spectroscopic studies had to deal with. This allows
  us to infer a binary frequency in the MUSE field of view and enables
  us to deduce the underlying true binary frequency of (6.75 ± 0.72)%
  in NGC 3201. The comparison of the MUSE observations with the MOCCA
  simulation suggests a large portion of primordial binaries. We can
  also confirm a radial increase in the binary fraction towards the
  cluster centre due to mass segregation. We discovered that in the core
  of NGC 3201 at least (57.5 ± 7.9)% of blue straggler stars are in a
  binary system. For the first time in a study of globular clusters,
  we were able to fit Keplerian orbits to a significant sample of 95
  binaries. We present the binary system properties of eleven blue
  straggler stars and the connection to SX Phoenicis-type stars. We
  show evidence that two blue straggler formation scenarios, the mass
  transfer in binary (or triple) star systems and the coalescence
  due to binary-binary interactions, are present in our data. We also
  describe the binary and spectroscopic properties of four sub-subgiant
  (or red straggler) stars. Furthermore, we discovered two new black
  hole candidates with minimum masses (M sin i) of (7.68 ± 0.50)
  M<SUB>⊙</SUB>, (4.4 ± 2.8) M<SUB>⊙</SUB>, and refine the minimum
  mass estimate on the already published black hole to (4.53 ± 0.21)
  M<SUB>⊙</SUB>. These black holes are consistent with an extensive
  black hole subsystem hosted by NGC 3201. <P />The full radial velocity
  sample (Table A.1) is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/632/A3">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/632/A3</A>

Title: The CARMENES search for exoplanets around M dwarfs. The He
    I triplet at 10830 Å across the M dwarf sequence
Authors: Fuhrmeister, B.; Czesla, S.; Hildebrandt, L.; Nagel, E.;
   Schmitt, J. H. M. M.; Hintz, D.; Johnson, E. N.; Sanz-Forcada, J.;
   Schöfer, P.; Jeffers, S. V.; Caballero, J. A.; Zechmeister, M.;
   Reiners, A.; Ribas, I.; Amado, P. J.; Quirrenbach, A.; Bauer, F. F.;
   Béjar, V. J. S.; Cortés-Contreras, M.; Díez-Alonso, E.; Dreizler,
   S.; Galadí-Enríquez, D.; Guenther, E. W.; Kaminski, A.; Kürster,
   M.; Lafarga, M.; Montes, D.
Bibcode: 2019A&A...632A..24F
Altcode: 2019arXiv191100246F
  The He I infrared (IR) triplet at 10 830 Å is an important activity
  indicator for the Sun and in solar-type stars, however, it has rarely
  been studied in relation to M dwarfs to date. In this study, we use the
  time-averaged spectra of 319 single stars with spectral types ranging
  from M0.0 V to M9.0 V obtained with the CARMENES high resolution
  optical and near-infrared spectrograph at Calar Alto to study the
  properties of the He I IR triplet lines. In quiescence, we find the
  triplet in absorption with a decrease of the measured pseudo equivalent
  width (pEW) towards later sub-types. For stars later than M5.0 V,
  the He I triplet becomes undetectable in our study. This dependence
  on effective temperature may be related to a change in chromospheric
  conditions along the M dwarf sequence. When an emission in the triplet
  is observed, we attribute it to flaring. The absence of emission during
  quiescence is consistent with line formation by photo-ionisation
  and recombination, while flare emission may be caused by collisions
  within dense material. The He I triplet tends to increase in depth
  according to increasing activity levels, ultimately becoming filled in;
  however, we do not find a correlation between the pEW(He IR) and X-ray
  properties. This behaviour may be attributed to the absence of very
  inactive stars (L<SUB>X</SUB>/L<SUB>bol</SUB> &lt; -5.5) in our sample
  or to the complex behaviour with regard to increasing depth and filling
  in. <P />Full Table 2 is only available at the CDS via anonymous ftp to
  <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/632/A24">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/632/A24</A>

Title: VizieR Online Data Catalog: EREBOS project. I. (Schaffenroth+,
    2019)
Authors: Schaffenroth, V.; Barlow, B. N.; Geier, S.; Vuckovic,
   M.; Kilkenny, D.; Wolz, M.; Kupfer, T.; Heber, U.; Drechsel, H.;
   Kimeswenger, S.; Marsh, T.; Wolf, M.; Pelisoli, I.; Freudenthal, J.;
   Dreizler, S.; Kreuzer, S.; Ziegerer, E.
Bibcode: 2019yCat..36300080S
Altcode:
  The EREBOS (Eclipsing Reflection Effect Binaries from Optical Surveys)
  project aims to study a large sample of homogeneously selected HW
  Vir systems (eclipsing binaries with cool stellar or substellar
  companions), and in particular their orbital, atmospheric, and
  fundamental parameters. <P />Two different photometric surveys
  are used to search such systems: OGLE (a long-term, large-scale
  photometric sky survey focused on variability, see Udalski et al.,
  2015AcA....65....1U) and ATLAS (a high-cadence all-sky survey system
  designed to find dangerous near-Earth asteroids, see Tonry et al.,
  2018PASP..130f4505T). The number of known HW Vir systems results
  increased by a factor of almost ten. <P />(6 data files).

Title: A stellar census in globular clusters with MUSE: multiple
    populations chemistry in NGC 2808
Authors: Latour, M.; Husser, T. -O.; Giesers, B.; Kamann, S.;
   Göttgens, F.; Dreizler, S.; Brinchmann, J.; Bastian, N.; Wendt, M.;
   Weilbacher, P. M.; Molinski, N. S.
Bibcode: 2019A&A...631A..14L
Altcode: 2019arXiv190904959L
  Context. Galactic globular clusters (GCs) are now known to host
  multiple populations displaying particular abundance variations. The
  different populations within a GC can be well distinguished following
  their position in the pseudo two-colors diagrams, also referred to as
  "chromosome maps". These maps are constructed using optical and near-UV
  photometry available from the Hubble Space Telescope (HST) UV survey
  of GCs. However, the chemical tagging of the various populations in
  the chromosome maps is hampered by the fact that HST photometry and
  elemental abundances are both only available for a limited number
  of stars. <BR /> Aims: The spectra collected as part of the MUSE
  survey of globular clusters provide a spectroscopic counterpart to
  the HST photometric catalogs covering the central regions of GCs. In
  this paper, we use the MUSE spectra of 1115 red giant branch (RGB)
  stars in NGC 2808 to characterize the abundance variations seen in
  the multiple populations of this cluster. <BR /> Methods: We used
  the chromosome map of NGC 2808 to divide the RGB stars into their
  respective populations. We then combined the spectra of all stars
  belonging to a given population, resulting in one high signal-to-noise
  ratio spectrum representative of each population. <BR /> Results:
  Variations in the spectral lines of O, Na, Mg, and Al are clearly
  detected among four of the populations. In order to quantify these
  variations, we measured equivalent width differences and created
  synthetic populations spectra that were used to determine abundance
  variations with respect to the primordial population of the cluster. Our
  results are in good agreement with the values expected from previous
  studies based on high-resolution spectroscopy. We do not see any
  significant variations in the spectral lines of Ca, K, and Ba. We
  also do not detect abundance variations among the stars belonging
  to the primordial population of NGC 2808. <BR /> Conclusions: We
  demonstrate that in spite of their low resolution, the MUSE spectra can
  be used to investigate abundance variations in the context of multiple
  populations. <P />The populations spectra and the list of stars included
  in these spectra are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/631/A14">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/631/A14</A>Based
  on observations collected at the European Organisation for Astronomical
  Research in the Southern Hemisphere, Chile (proposal IDs 094.D-0142(B),
  096.D-0175(A)).

Title: A stellar census in globular clusters with MUSE: A spectral
    catalogue of emission-line sources
Authors: Göttgens, Fabian; Husser, Tim-Oliver; Kamann, Sebastian;
   Dreizler, Stefan; Giesers, Benjamin; Kollatschny, Wolfram; Weilbacher,
   Peter M.; Roth, Martin M.; Wendt, Martin
Bibcode: 2019A&A...631A.118G
Altcode: 2019arXiv190905872G
  <BR /> Aims: Globular clusters produce many exotic stars due to
  a much higher frequency of dynamical interactions in their dense
  stellar environments. Some of these objects were observed together
  with several hundred thousand other stars in our MUSE survey of 26
  Galactic globular clusters. Assuming that at least a few exotic stars
  have exotic spectra (i.e. spectra that contain emission lines), we
  can use this large spectroscopic data set of over a million stellar
  spectra as a blind survey to detect stellar exotica in globular
  clusters. <BR /> Methods: To detect emission lines in each spectrum,
  we modelled the expected shape of an emission line as a Gaussian
  curve. This template was used for matched filtering on the differences
  between each observed 1D spectrum and its fitted spectral model. The
  spectra with the most significant detections of Hα emission are
  checked visually and cross-matched with published catalogues. <BR
  /> Results: We find 156 stars with Hα emission, including several
  known cataclysmic variables (CV) and two new CVs, pulsating variable
  stars, eclipsing binary stars, the optical counterpart of a known
  black hole, several probable sub-subgiants and red stragglers,
  and 21 background emission-line galaxies. We find possible optical
  counterparts to 39 X-ray sources, as we detected Hα emission in several
  spectra of stars that are close to known positions of Chandra X-ray
  sources. This spectral catalogue can be used to supplement existing
  or future X-ray or radio observations with spectra of potential
  optical counterparts to classify the sources. <P />Table A.2 and
  spectra (FITS) are available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/631/A118">http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/631/A118</A>

Title: VizieR Online Data Catalog: NGC 6397 stars MUSE spectra
    (Husser+, 2016)
Authors: Husser, T. -O.; Kamann, S.; Dreizler, S.; Wendt, M.; Wulff,
   N.; Bacon, R.; Wisotzki, L.; Brinchmann, J.; Weilbacher, P. M.; Roth,
   M. M.; Monreal-Ibero, A.
Bibcode: 2019yCat..35880148H
Altcode:
  We observed the globular cluster NGC 6397 during MUSE commissioning,
  lasting from July 26nd to August 3rd, 2014, to explore the capabilities
  of MUSE in crowded stellar fields. <P />To obtain clean spectra in
  a crowded region such as a globular cluster, sophisticated analysis
  techniques are required. <P />Provided are all the obtained spectra
  with a signal-to-noise ratio of five or larger, i.e. 14271 spectra in
  total. <P />(3 data files).

Title: VizieR Online Data Catalog: NGC 2808 stellar population spectra
    (Latour+, 2019)
Authors: Latour, M.; Husser, T. -O.; Giesers, B.; Kamann, S.;
   Goettgens, F.; Dreizler, S.; Brinchmann, J.; Bastian, N.; Wendt, M.;
   Weilbacher, P. M.; Molinski, N. S.
Bibcode: 2019yCat..36310014L
Altcode:
  We provide the summed spectra of population 1 to 4. The radial
  velocities are corrected so that the spectrum are at rest
  wavelength. The table includes the list of stars whose spectrum are
  included in the combined spectra along with their population number. <P
  />(3 data files).

Title: No evidence for intermediate-mass black holes in the globular
    clusters ω Cen and NGC 6624
Authors: Baumgardt, H.; He, C.; Sweet, S. M.; Drinkwater, M.; Sollima,
   A.; Hurley, J.; Usher, C.; Kamann, S.; Dalgleish, H.; Dreizler, S.;
   Husser, T. -O.
Bibcode: 2019MNRAS.488.5340B
Altcode: 2019arXiv190710845B; 2019MNRAS.tmp.1999B
  We compare the results of a large grid of N-body simulations with the
  surface brightness and velocity dispersion profiles of the globular
  clusters ω Cen and NGC 6624. Our models include clusters with varying
  stellar-mass black hole retention fractions and varying masses of a
  central intermediate-mass black hole (IMBH). We find that an ∼ 45
  000 M<SUB>⊙</SUB> IMBH, whose presence has been suggested based
  on the measured velocity dispersion profile of ω Cen, predicts
  the existence of about 20 fast-moving, m &gt; 0.5 M<SUB>⊙</SUB>,
  main-sequence stars with a (1D) velocity v &gt; 60 km s<SUP>-1</SUP>
  in the central 20 arcsec of ω Cen. However, no such star is present
  in the HST/ACS proper motion catalogue of Bellini et al. (2017),
  strongly ruling out the presence of a massive IMBH in the core of
  ω Cen. Instead, we find that all available data can be fitted by a
  model that contains 4.6 per cent of the mass of ω Cen in a centrally
  concentrated cluster of stellar-mass black holes. We show that this
  mass fraction in stellar-mass BHs is compatible with the predictions of
  stellar evolution models of massive stars. We also compare our grid of
  N-body simulations with NGC 6624, a cluster recently claimed to harbour
  a 20 000 M<SUB>⊙</SUB> black hole based on timing observations of
  millisecond pulsars. However, we find that models with M<SUB>IMBH</SUB>
  &gt; 1000 M<SUB>⊙</SUB> IMBHs are incompatible with the observed
  velocity dispersion and surface brightness profile of NGC 6624, ruling
  out the presence of a massive IMBH in this cluster. Models without an
  IMBH provide again an excellent fit to NGC 6624.

Title: The EREBOS project: Investigating the effect of substellar
    and low-mass stellar companions on late stellar evolution. Survey,
    target selection, and atmospheric parameters
Authors: Schaffenroth, V.; Barlow, B. N.; Geier, S.; Vučković,
   M.; Kilkenny, D.; Wolz, M.; Kupfer, T.; Heber, U.; Drechsel, H.;
   Kimeswenger, S.; Marsh, T.; Wolf, M.; Pelisoli, I.; Freudenthal, J.;
   Dreizler, S.; Kreuzer, S.; Ziegerer, E.
Bibcode: 2019A&A...630A..80S
Altcode: 2019arXiv190709892S
  Eclipsing post-common-envelope binaries are highly important for
  resolving the poorly understood, very short-lived common-envelope
  phase of stellar evolution. Most hot subdwarfs (sdO/Bs) are the bare
  helium-burning cores of red giants that have lost almost all of their
  hydrogen envelope. This mass loss is often triggered by common-envelope
  interactions with close stellar or even substellar companions. Cool
  companions to hot subdwarf stars such as late-type stars and brown
  dwarfs are detectable from characteristic light-curve variations -
  reflection effects and often eclipses. In the recently published
  catalog of eclipsing binaries in the Galactic Bulge and in the Asteroid
  Terrestrial-impact Last Alert System (ATLAS) survey, we discovered
  125 new eclipsing systems showing a reflection effect seen by visual
  inspection of the light curves and using a machine-learning algorithm,
  in addition to the 36 systems previously discovered by the Optical
  Gravitational Lesing Experiment (OGLE) team. The Eclipsing Reflection
  Effect Binaries from Optical Surveys (EREBOS) project aims at analyzing
  all newly discovered eclipsing binaries of the HW Vir type (hot subdwarf
  + close, cool companion) based on a spectroscopic and photometric
  follow up to derive the mass distribution of the companions, constrain
  the fraction of substellar companions, and determine the minimum mass
  needed to strip off the red-giant envelope. To constrain the nature of
  the primary we derived the absolute magnitude and the reduced proper
  motion of all our targets with the help of the parallaxes and proper
  motions measured by the Gaia mission and compared those to the Gaia
  white-dwarf candidate catalog. It was possible to derive the nature
  of a subset of our targets, for which observed spectra are available,
  by measuring the atmospheric parameter of the primary, confirming
  that less than 10% of our systems are not sdO/Bs with cool companions
  but are white dwarfs or central stars of planetary nebula. This large
  sample of eclipsing hot subdwarfs with cool companions allowed us to
  derive a significant period distribution for hot subdwarfs with cool
  companions for the first time showing that the period distribution is
  much broader than previously thought and is ideally suited to finding
  the lowest-mass companions to hot subdwarf stars. The comparison
  with related binary populations shows that the period distribution
  of HW Vir systems is very similar to WD+dM systems and central stars
  of planetary nebula with cool companions. In the future, several new
  photometric surveys will be carried out, which will further increase
  the sample of this project, providing the potential to test many
  aspects of common-envelope theory and binary evolution.

Title: VizieR Online Data Catalog: HeI IR triplet measurements for
    M dwarfs (Fuhrmeister+, 2019)
Authors: Fuhrmeister, B.; Czesla, S.; Hildebrandt, L.; Nagel, E.;
   Schmitt, J. H. M. M.; Hintz, D.; Johnson, E. N.; Sanz-Forcada, J.;
   Schoefer, P.; Jeffers, S. V.; Caballero, J. A.; Zechmeister, M.;
   Reiners, A.; Ribas, I.; Amado, P. J.; Quirrenbach, A.; Bauer, F. F.;
   Bejar, V. J. S.; Cortes-Contreras, M.; Diez-Alonso, E.; Dreizler,
   S.; Galadi-Enriquez, D.; Guenther, E. W.; Kaminski, A.; Kuerster,
   M.; Lafarga, M.; Montes, D.
Bibcode: 2019yCat..36320024F
Altcode:
  We measure the pseudo-equivalent width (pEW) in the averaged stellar
  spectra using a Voigt fit with four Voigt components to account for
  neighbouring lines. The fit does not account for the bluest HeI triplet
  component and treats the two redder components as one component as they
  are totally blended for the used resolution of 80400. For comparison
  purposes we give also pEW values of Hα, the bluest CaII IR triplet
  line, and the HeI D<SUB>3</SUB> line which were obtained by integration
  over the line from the same spectra. As a further comparison for the
  activity level of the star we give LX/Lbol values mostly taken from
  the ROSAT all-sky survey. <P />(1 data file).

Title: A giant exoplanet orbiting a very-low-mass star challenges
    planet formation models
Authors: Morales, J. C.; Mustill, A. J.; Ribas, I.; Davies, M. B.;
   Reiners, A.; Bauer, F. F.; Kossakowski, D.; Herrero, E.; Rodríguez,
   E.; López-González, M. J.; Rodríguez-López, C.; Béjar, V. J. S.;
   González-Cuesta, L.; Luque, R.; Pallé, E.; Perger, M.; Baroch,
   D.; Johansen, A.; Klahr, H.; Mordasini, C.; Anglada-Escudé, G.;
   Caballero, J. A.; Cortés-Contreras, M.; Dreizler, S.; Lafarga, M.;
   Nagel, E.; Passegger, V. M.; Reffert, S.; Rosich, A.; Schweitzer,
   A.; Tal-Or, L.; Trifonov, T.; Zechmeister, M.; Quirrenbach, A.;
   Amado, P. J.; Guenther, E. W.; Hagen, H. -J.; Henning, T.; Jeffers,
   S. V.; Kaminski, A.; Kürster, M.; Montes, D.; Seifert, W.; Abellán,
   F. J.; Abril, M.; Aceituno, J.; Aceituno, F. J.; Alonso-Floriano,
   F. J.; Ammler-von Eiff, M.; Antona, R.; Arroyo-Torres, B.; Azzaro,
   M.; Barrado, D.; Becerril-Jarque, S.; Benítez, D.; Berdiñas, Z. M.;
   Bergond, G.; Brinkmöller, M.; del Burgo, C.; Burn, R.; Calvo-Ortega,
   R.; Cano, J.; Cárdenas, M. C.; Cardona Guillén, C.; Carro, J.; Casal,
   E.; Casanova, V.; Casasayas-Barris, N.; Chaturvedi, P.; Cifuentes,
   C.; Claret, A.; Colomé, J.; Czesla, S.; Díez-Alonso, E.; Dorda, R.;
   Emsenhuber, A.; Fernández, M.; Fernández-Martín, A.; Ferro, I. M.;
   Fuhrmeister, B.; Galadí-Enríquez, D.; Gallardo Cava, I.; García
   Vargas, M. L.; Garcia-Piquer, A.; Gesa, L.; González-Álvarez,
   E.; González Hernández, J. I.; González-Peinado, R.; Guàrdia,
   J.; Guijarro, A.; de Guindos, E.; Hatzes, A. P.; Hauschildt, P. H.;
   Hedrosa, R. P.; Hermelo, I.; Hernández Arabi, R.; Hernández Otero,
   F.; Hintz, D.; Holgado, G.; Huber, A.; Huke, P.; Johnson, E. N.;
   de Juan, E.; Kehr, M.; Kemmer, J.; Kim, M.; Klüter, J.; Klutsch,
   A.; Labarga, F.; Labiche, N.; Lalitha, S.; Lampón, M.; Lara, L. M.;
   Launhardt, R.; Lázaro, F. J.; Lizon, J. -L.; Llamas, M.; Lodieu,
   N.; López del Fresno, M.; López Salas, J. F.; López-Santiago, J.;
   Magán Madinabeitia, H.; Mall, U.; Mancini, L.; Mandel, H.; Marfil,
   E.; Marín Molina, J. A.; Martín, E. L.; Martín-Fernández, P.;
   Martín-Ruiz, S.; Martínez-Rodríguez, H.; Marvin, C. J.; Mirabet,
   E.; Moya, A.; Naranjo, V.; Nelson, R. P.; Nortmann, L.; Nowak, G.;
   Ofir, A.; Pascual, J.; Pavlov, A.; Pedraz, S.; Pérez Medialdea, D.;
   Pérez-Calpena, A.; Perryman, M. A. C.; Rabaza, O.; Ramón Ballesta,
   A.; Rebolo, R.; Redondo, P.; Rix, H. -W.; Rodler, F.; Rodríguez
   Trinidad, A.; Sabotta, S.; Sadegi, S.; Salz, M.; Sánchez-Blanco,
   E.; Sánchez Carrasco, M. A.; Sánchez-López, A.; Sanz-Forcada, J.;
   Sarkis, P.; Sarmiento, L. F.; Schäfer, S.; Schlecker, M.; Schmitt,
   J. H. M. M.; Schöfer, P.; Solano, E.; Sota, A.; Stahl, O.; Stock, S.;
   Stuber, T.; Stürmer, J.; Suárez, J. C.; Tabernero, H. M.; Tulloch,
   S. M.; Veredas, G.; Vico-Linares, J. I.; Vilardell, F.; Wagner, K.;
   Winkler, J.; Wolthoff, V.; Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2019Sci...365.1441M
Altcode: 2019arXiv190912174M
  Surveys have shown that super-Earth and Neptune-mass exoplanets are more
  frequent than gas giants around low-mass stars, as predicted by the core
  accretion theory of planet formation. We report the discovery of a giant
  planet around the very-low-mass star GJ 3512, as determined by optical
  and near-infrared radial-velocity observations. The planet has a minimum
  mass of 0.46 Jupiter masses, very high for such a small host star,
  and an eccentric 204-day orbit. Dynamical models show that the high
  eccentricity is most likely due to planet-planet interactions. We use
  simulations to demonstrate that the GJ 3512 planetary system challenges
  generally accepted formation theories, and that it puts constraints
  on the planet accretion and migration rates. Disk instabilities may
  be more efficient in forming planets than previously thought.

Title: VizieR Online Data Catalog: Emission-line sources MUSE spectral
    catalogue (Goettgens+, 2019)
Authors: Goettgens, F.; Husser, T. -O.; Kamann, S.; Dreizler, S.;
   Giesers, B.; Kollatschny, W.; Weilbacher, P. M.; Roth, M. M.; Wendt, M.
Bibcode: 2019yCat..36310118G
Altcode:
  The spectra were extracted from datacubes taken with MUSE at the VLT. We
  used matched filtering to search for emission-line objects (ELOs) in
  globular clusters. The tables contain the properties of the detected
  ELOs, including references to the literature. Please see the paper
  for details about which filter was used for the reported V magnitude,
  and which conventions are used for the cluster membership indicator
  and the indicator for radial velocity variations. <P />(3 data files).

Title: VizieR Online Data Catalog: MUSE binaries in NGC 3201
    (Giesers+, 2019)
Authors: Giesers, B.; Kamann, S.; Dreizler, S.; Husser, T. -O.;
   Askar, A.; Goettgens, F.; Brinchmann, J.; Latour, M.; Weilbacher,
   P. M.; Wendt, M.; Roth, M. M.
Bibcode: 2019yCat..36320003G
Altcode:
  Since 2014, 27 Galactic globular clusters were observed (PI: S. Kamann,
  formerly S. Dreizler) with the integral field spectrograph Multi Unit
  Spectroscopic Explorer (MUSE) at the Very Large Telescope (VLT; Kamann
  et al. 2018MNRAS.473.5591K). In the wide field mode, MUSE covers a 1'x1'
  field of view (FoV) with a spatial sampling of 0.2" and a spectral
  sampling of 1.25Å (resolving power of 1770&lt;R&lt;3590) in the
  wavelength range from 4750 to 9350Å. MUSE allows to extract spectra
  of some thousand stars per exposure. For this paper, all observations
  of NGC 3201 obtained before May 2019 were used. In addition to the
  pointings listed in Kamann et al. (2018MNRAS.473.5591K), a deep
  field was also implemented. Table 1 lists the number of visits and
  total integration times for the different pointings. The data include
  adaptive optics (AO) observations, the standard observing mode since
  the AO system was commissioned in October 2017. The AO observations are
  treated in the same way as our previous observations.The only difference
  is that a wavelength window of each spectrum around the sodium lines
  (5805Å-5965Å) has to be masked due to the AO laser emission. The
  catalogue includes the full radial velocity sample obtained from 63
  MUSE observations done for different pointings in NGC 3201 and the
  orbital parameters of the 95 well constrained binaries in NGC 3201. <P
  />(5 data files).

Title: First light of engineered diffusers at the Nordic Optical
    Telescope reveal time variability of the optical eclipse depth
    of WASP-12b
Authors: von Essen, C.; Stefansson, G.; Mallonn, M.; Pursimo,
   T.; Djupvik, A. A.; Mahadevan, S.; Kjeldsen, H.; Freudenthal, J.;
   Dreizler, S.
Bibcode: 2019A&A...628A.115V
Altcode: 2019arXiv190405362V
  We present the characterization of two engineered diffusers mounted
  on the 2.5-meter Nordic Optical Telescope, located at Roque de
  Los Muchachos, Spain. To assess the reliability and the efficiency
  of the diffusers, we carried out several test observations of two
  photometric standard stars, along with observations of one primary
  transit observation of TrES-3b in the red (R band), one of CoRoT-1b
  in the blue (B band), and three secondary eclipses of WASP-12b (V
  band). The achieved photometric precision is in all cases within the
  submillimagnitude level for exposures between 25 and 180 s. Along
  with a detailed analysis of the functionality of the diffusers,
  we add a new transit depth measurement in the blue (B band) to the
  already observed transmission spectrum of CoRoT-1b, disfavoring
  a Rayleigh slope. We also report variability of the eclipse depth
  of WASP-12b in the V band. For the WASP-12b secondary eclipses, we
  observe a secondary depth deviation of about 5σ, and a difference of
  6σ and 2.5σ when compared to the values reported by other authors
  in a similar wavelength range determined from Hubble Space Telescope
  data. We further speculate about the potential physical processes or
  causes responsible for this observed variability. <P />The data of the
  light curves are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/628/A115">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/628/A115</A>

Title: VizieR Online Data Catalog: Abundances for 79 Sun-like stars
    within 100pc (Bedell+, 2018)
Authors: Bedell, M.; Bean, J. L.; Melendez, J.; Spina, L.; Ramirez,
   I.; Asplund, M.; Alves-Brito, A.; Dos Santos, L.; Dreizler, S.; Yong,
   D.; Monroe, T.; Casagrande, L.
Bibcode: 2019yCat..18650068B
Altcode:
  To achieve sufficient signal-to-noise for high-precision abundance
  work, we stacked &gt;=50 observations for each star. All spectra were
  taken with the High Accuracy Radial velocity Planet Searcher (HARPS)
  spectrograph on the 3.6m telescope of the European Southern Observatory
  (ESO), located at La Silla Observatory in Chile; with resolving power
  R=115000 and wavelength coverage between 378-691nm. A majority of
  the selected sample were observed by us in the course of a large ESO
  observing program on HARPS (Melendez+ 2015Msngr.161...28M). Other stars
  had a sufficient number of publicly available spectra in the online
  ESO Science Archive Facility. <P />The solar reference spectrum used
  in this work was created by combining multiple exposures of sunlight
  reflected from the asteroid Vesta. It was continuum-normalized in the
  same manner as the target spectra and has S/N~1300/pix at 600nm. <P
  />Spectra previously obtained with the MIKE spectrograph and analyzed
  in Ramirez+ (2014A&amp;A...572A..48R) were also used in some parts
  of this analysis. These spectra have S/N~400/pix at 600nm, resolution
  R=83000-65000 (on blue/red CCDs), and wavelength coverage between 320
  and 1000nm. <P />(2 data files).

Title: Planetary system around the nearby M dwarf GJ 357 including
    a transiting, hot, Earth-sized planet optimal for atmospheric
    characterization
Authors: Luque, R.; Pallé, E.; Kossakowski, D.; Dreizler, S.; Kemmer,
   J.; Espinoza, N.; Burt, J.; Anglada-Escudé, G.; Béjar, V. J. S.;
   Caballero, J. A.; Collins, K. A.; Collins, K. I.; Cortés-Contreras,
   M.; Díez-Alonso, E.; Feng, F.; Hatzes, A.; Hellier, C.; Henning,
   T.; Jeffers, S. V.; Kaltenegger, L.; Kürster, M.; Madden, J.;
   Molaverdikhani, K.; Montes, D.; Narita, N.; Nowak, G.; Ofir, A.;
   Oshagh, M.; Parviainen, H.; Quirrenbach, A.; Reffert, S.; Reiners,
   A.; Rodríguez-López, C.; Schlecker, M.; Stock, S.; Trifonov, T.;
   Winn, J. N.; Zapatero Osorio, M. R.; Zechmeister, M.; Amado, P. J.;
   Anderson, D. R.; Batalha, N. E.; Bauer, F. F.; Bluhm, P.; Burke, C. J.;
   Butler, R. P.; Caldwell, D. A.; Chen, G.; Crane, J. D.; Dragomir,
   D.; Dressing, C. D.; Dynes, S.; Jenkins, J. M.; Kaminski, A.; Klahr,
   H.; Kotani, T.; Lafarga, M.; Latham, D. W.; Lewin, P.; McDermott,
   S.; Montañés-Rodríguez, P.; Morales, J. C.; Murgas, F.; Nagel,
   E.; Pedraz, S.; Ribas, I.; Ricker, G. R.; Rowden, P.; Seager, S.;
   Shectman, S. A.; Tamura, M.; Teske, J.; Twicken, J. D.; Vanderspeck,
   R.; Wang, S. X.; Wohler, B.
Bibcode: 2019A&A...628A..39L
Altcode: 2019arXiv190412818L
  We report the detection of a transiting Earth-size planet around GJ
  357, a nearby M2.5 V star, using data from the Transiting Exoplanet
  Survey Satellite (TESS). GJ 357 b (TOI-562.01) is a transiting, hot,
  Earth-sized planet (T<SUB>eq</SUB> = 525 ± 11 K) with a radius of
  R<SUB>b</SUB> = 1.217 ± 0.084 R<SUB>⊕</SUB> and an orbital period
  of P<SUB>b</SUB> = 3.93 d. Precise stellar radial velocities from
  CARMENES and PFS, as well as archival data from HIRES, UVES, and
  HARPS also display a 3.93-day periodicity, confirming the planetary
  nature and leading to a planetary mass of M<SUB>b</SUB> = 1.84 ± 0.31
  M<SUB>⊕</SUB>. In addition to the radial velocity signal for GJ 357
  b, more periodicities are present in the data indicating the presence
  of two further planets in the system: GJ 357 c, with a minimum mass
  of M<SUB>c</SUB> = 3.40 ± 0.46 M<SUB>⊕</SUB> in a 9.12 d orbit,
  and GJ 357 d, with a minimum mass of M<SUB>d</SUB> = 6.1 ± 1.0
  M<SUB>⊕</SUB> in a 55.7 d orbit inside the habitable zone. The host
  is relatively inactive and exhibits a photometric rotation period of
  P<SUB>rot</SUB> = 78 ± 2 d. GJ 357 b isto date the second closest
  transiting planet to the Sun, making it a prime target for further
  investigations such as transmission spectroscopy. Therefore, GJ 357 b
  represents one of the best terrestrial planets suitable for atmospheric
  characterization with the upcoming JWST and ground-based ELTs. <P
  />RV data are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/628/A39">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/628/A39</A>

Title: Rocky planets from the CARMENES Survey
Authors: Dreizler, Stefan
Bibcode: 2019ESS.....410202D
Altcode:
  Since the first discovery, more than 800 exoplanets have been detected
  through the radial velocity method, the majority orbiting solar-like
  stars. Although M-stars are the most frequent stars, very few planets
  have yet been found around M-stars of late spectral type. <P />CARMENES,
  operated since 2016, is a high-resolution visible-near-IR spectrograph
  dedicated to search for such low-mass planets around low-mass stars and
  already doubled the number of known planets with host stars below 0.2
  M<SUB>Sun</SUB>. Not surprisingly, also this stellar parameter range
  has its surprises in terms of planetary system architectures. We will
  give an overview of exoplanet detections (published and unpublished)
  from the CARMENES survey and then concentrate on the low-mass planets,
  including the very recent detection of two Earth-mass planets around
  Teegarden's star highlighting the capability of CARMENES. The planetary
  system is special since Teegarden's star is only one out of three
  planet host stars with an effective temperature below 3000K. Its two
  planets are within the optimistic and conservative habitable zone,
  respectively. Notably, the Earth, as well as other Solar System planets
  are currently or in near future in the transit visibility zone see
  from Teegarden's star.

Title: VizieR Online Data Catalog: WASP-12, CoRoT-1 and TrES-3 light
    curves (von Essen+, 2019)
Authors: von Essen, C.; Stefansson, G.; Mallonn, M.; Pursimo,
   T.; Djupvik, A. A.; Mahadevan, S.; Kjeldsen, H.; Freudenthal, J.;
   Dreizler, S.
Bibcode: 2019yCat..36280115V
Altcode:
  5 differential photometry time series of primary transit events (first
  two) and secondary transit events (last three) of three different
  extrasolar planets. <P />(1 data file).

Title: Kepler Object of Interest Network. III. Kepler-82f: a new
    non-transiting 21 M<SUB>⊕</SUB> planet from photodynamical modelling
Authors: Freudenthal, J.; von Essen, C.; Ofir, A.; Dreizler, S.; Agol,
   E.; Wedemeyer, S.; Morris, B. M.; Becker, A. C.; Deeg, H. J.; Hoyer,
   S.; Mallonn, M.; Poppenhaeger, K.; Herrero, E.; Ribas, I.; Boumis,
   P.; Liakos, A.
Bibcode: 2019A&A...628A.108F
Altcode: 2019arXiv190706534F
  Context. The Kepler Object of Interest Network (KOINet) is a
  multi-site network of telescopes around the globe organised for
  follow-up observations of transiting planet candidate Kepler objects of
  interest with large transit timing variations (TTVs). The main goal of
  KOINet is the completion of their TTV curves as the Kepler telescope
  stopped observing the original Kepler field in 2013. <BR /> Aims: We
  ensure a comprehensive characterisation of the investigated systems
  by analysing Kepler data combined with new ground-based transit data
  using a photodynamical model. This method is applied to the Kepler-82
  system leading to its first dynamic analysis. <BR /> Methods: In order
  to provide a coherent description of all observations simultaneously,
  we combine the numerical integration of the gravitational dynamics of
  a system over the time span of observations with a transit light curve
  model. To explore the model parameter space, this photodynamical model
  is coupled with a Markov chain Monte Carlo algorithm. <BR /> Results:
  The Kepler-82b/c system shows sinusoidal TTVs due to their near 2:1
  resonance dynamical interaction. An additional chopping effect in
  the TTVs of Kepler-82c hints to a further planet near the 3:2 or 3:1
  resonance. We photodynamically analysed Kepler long- and short-cadence
  data and three new transit observations obtained by KOINet between 2014
  and 2018. Our result reveals a non-transiting outer planet with a mass
  of m<SUB>f</SUB> = 20.9 ± 1.0 M<SUB>⊕</SUB> near the 3:2 resonance to
  the outermost known planet, Kepler-82c. Furthermore, we determined the
  densities of planets b and c to the significantly more precise values
  ρ<SUB>b</SUB> = 0.98<SUB>-0.14</SUB><SUP>+0.10</SUP> g cm<SUP>-3</SUP>
  and ρ<SUB>c</SUB> = 0.494<SUB>-0.077</SUB><SUP>+0.066</SUP>
  g cm<SUP>-3</SUP>. <P />Ground-based photometry
  is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/628/A108">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/628/A108</A>

Title: The CARMENES search for exoplanets around M
    dwarfs. Photospheric parameters of target stars from high-resolution
    spectroscopy. II. Simultaneous multiwavelength range modeling of
    activity insensitive lines
Authors: Passegger, V. M.; Schweitzer, A.; Shulyak, D.; Nagel, E.;
   Hauschildt, P. H.; Reiners, A.; Amado, P. J.; Caballero, J. A.;
   Cortés-Contreras, M.; Domínguez-Fernández, A. J.; Quirrenbach,
   A.; Ribas, I.; Azzaro, M.; Anglada-Escudé, G.; Bauer, F. F.; Béjar,
   V. J. S.; Dreizler, S.; Guenther, E. W.; Henning, T.; Jeffers, S. V.;
   Kaminski, A.; Kürster, M.; Lafarga, M.; Martín, E. L.; Montes, D.;
   Morales, J. C.; Schmitt, J. H. M. M.; Zechmeister, M.
Bibcode: 2019A&A...627A.161P
Altcode: 2019arXiv190700807P
  We present precise photospheric parameters of 282 M dwarfs
  determined from fitting the most recent version of PHOENIX models to
  high-resolution CARMENES spectra in the visible (0.52-0.96 μm) and NIR
  wavelength range (0.96-1.71 μm). With its aim to search for habitable
  planets around M dwarfs, several planets of different masses have
  been detected. The characterization of the target sample is important
  for the ability to derive and constrain the physical properties of any
  planetary systems that are detected. As a continuation of previous work
  in this context, we derived the fundamental stellar parameters effective
  temperature, surface gravity, and metallicity of the CARMENES M-dwarf
  targets from PHOENIX model fits using a χ<SUP>2</SUP> method. We
  calculated updated PHOENIX stellar atmosphere models that include a
  new equation of state to especially account for spectral features
  of low-temperature stellar atmospheres as well as new atomic and
  molecular line lists. We show the importance of selecting magnetically
  insensitive lines for fitting to avoid effects of stellar activity
  in the line profiles. For the first time, we directly compare stellar
  parameters derived from multiwavelength range spectra, simultaneously
  observed for the same star. In comparison with literature values we
  show that fundamental parameters derived from visible spectra and
  visible and NIR spectra combined are in better agreement than those
  derived from the same spectra in the NIR alone. <P />Full Tables
  B.1 and B.2 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A161">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A161</A>

Title: VizieR Online Data Catalog: Radial velocities of GJ 357
    (Luque+, 2019)
Authors: Luque, R.; Palle, E.; Kossakowski, D.; Dreizler, S.; Kemmer,
   J.; Espinoza, N.; Burt, J.; Anglada-Escude, G.; Bejar, V. J. S.;
   Caballero, J. A.; Collins, K. A.; Collins, K. I.; Cortes-Contreras,
   M.; Diez-Alonso, E.; Feng, F.; Hatzes, A.; Hellier, C.; Henning,
   T.; Jeffers, S. V.; Kaltenegger, L.; Kuerster, M.; Madden, J.;
   Molaverdikhani, K.; Montes, D.; Narita, N.; Nowak, G.; Ofir, A.;
   Oshagh, M.; Parviainen, H.; Quirrenbach, A.; Reffert, S.; Reiners,
   A.; Rodriguez-Lopez, C.; Schlecker, M.; Stock, S.; Trifonov, T.;
   Winn, J. N.; Zapatero Osorio, M. R.; Zechmeister, M.; Amado, P. J.;
   Anderson, D. R.; Batalha, N. E.; Bauer, F. F.; Bluhm, P.; Burke, C. J.;
   Butler, R. P.; Caldwell, D. A.; Chen, G.; Crane, J. D.; Dragomir,
   D.; Dressing, C. D.; Dynes, S.; Jenkins, J. M.; Kaminski, A.; Klahr,
   H.; Kotani, T.; Lafarga, M.; Latham, D. W.; Lewin, P.; McDermott, S.;
   Montanes-Rodriguez, P.; Morales, J. C.; Murgas, F.; Nagel, E.; Pedraz,
   S.; Ribas, I.; Ricker, G. R.; Rowden, P.; Seager, S.; Shectman, S. A.;
   Tamura, M.; Teske, J.; Twicken, J. D.; Vanderspeck, R.; Wang, S. X.;
   Wohler, B.
Bibcode: 2019yCat..36280039L
Altcode:
  Radial velocities of GJ 357 from HIRES (Vogt et al., 1994, in
  Proc. SPIE, Vol. 2198, 362), UVES (programs 072.C-0495, 078.C-0829,
  and 173.C-0606), HARPS (Mayor et al., 2003Msngr.114...20M; programs
  072.C-0488, 183.C-0437), CARMENES (Quirrenbach et al., 2016, in
  Proc. SPIE, Vol. 9147,91471F; 2018, in Society of Photo-Optical
  Instrumentation Engineers (SPIE) Conference Series, Vol. 10702,
  107020W), and PFS (Crane et al., 2010aepr.confE..19C). <P />(1 data
  file).

Title: Proxima Centauri b is not a transiting exoplanet
Authors: Jenkins, James S.; Harrington, Joseph; Challener, Ryan C.;
   Kurtovic, Nicolás T.; Ramirez, Ricardo; Peña, Jose; McIntyre,
   Kathleen J.; Himes, Michael D.; Rodríguez, Eloy; Anglada-Escudé,
   Guillem; Dreizler, Stefan; Ofir, Aviv; Peña Rojas, Pablo A.; Ribas,
   Ignasi; Rojo, Patricio; Kipping, David; Butler, R. Paul; Amado, Pedro
   J.; Rodríguez-López, Cristina; Kempton, Eliza M. -R.; Palle, Enric;
   Murgas, Felipe
Bibcode: 2019MNRAS.487..268J
Altcode: 2019MNRAS.tmp.1236J; 2019arXiv190501336J
  We report Spitzer Space Telescope observations during predicted transits
  of the exoplanet Proxima Centauri b. As the nearest terrestrial
  habitable-zone planet we will ever discover, any potential transit
  of Proxima b would place strong constraints on its radius, bulk
  density, and atmosphere. Subsequent transmission spectroscopy and
  secondary-eclipse measurements could then probe the atmospheric
  chemistry, physical processes, and orbit, including a search for
  biosignatures. However, our photometric results rule out planetary
  transits at the 200 ppm level at 4.5 μm, yielding a 3σ upper
  radius limit of 0.4 R<SUB>⊕</SUB> (Earth radii). Previous claims of
  possible transits from optical ground- and space-based photometry were
  likely correlated noise in the data from Proxima Centauri's frequent
  flaring. Our study indicates dramatically reduced stellar activity at
  near-to-mid infrared wavelengths, compared to the optical. Proxima
  b is an ideal target for space-based infrared telescopes, if their
  instruments can be configured to handle Proxima's brightness.

Title: The CARMENES search for exoplanets around M dwarfs. Detection
    of a mini-Neptune around LSPM J2116+0234 and refinement of orbital
    parameters of a super-Earth around GJ 686 (BD+18 3421)
Authors: Lalitha, S.; Baroch, D.; Morales, J. C.; Passegger, V. M.;
   Bauer, F. F.; Cardona Guillén, C.; Dreizler, S.; Oshagh, M.; Reiners,
   A.; Ribas, I.; Caballero, J. A.; Quirrenbach, A.; Amado, P. J.; Béjar,
   V. J. S.; Colomé, J.; Cortés-Contreras, M.; Galadí-Enríquez, D.;
   González-Cuesta, L.; Guenther, E. W.; Hagen, H. -J.; Henning, T.;
   Herrero, E.; Husser, T. -O.; Jeffers, S. V.; Kaminski, A.; Kürster,
   M.; Lafarga, M.; Lodieu, N.; López-González, M. J.; Montes, D.;
   Perger, M.; Rosich, A.; Rodríguez, E.; Rodríguez-López, C.; Schmitt,
   J. H. M. M.; Tal-Or, L.; Zechmeister, M.
Bibcode: 2019A&A...627A.116L
Altcode: 2019arXiv190509075L
  Although M dwarfs are known for high levels of stellar activity,
  they are ideal targets for the search of low-mass exoplanets
  with the radial velocity (RV) method. We report the discovery of a
  planetary-mass companion around LSPM J2116+0234 (M3.0 V) and confirm
  the existence of a planet orbiting GJ 686 (BD+18 3421; M1.0 V). The
  discovery of the planet around LSPM J2116+0234 is based on CARMENES
  RV observations in the visual and near-infrared channels. We confirm
  the planet orbiting around GJ 686 by analyzing the RV data spanning
  over two decades of observationsfrom CARMENES VIS, HARPS-N, HARPS,
  and HIRES. We find planetary signals at 14.44 and 15.53 d in the
  RV data for LSPM J2116+0234 and GJ 686, respectively. Additionally,
  the RV, photometric time series, and various spectroscopic indicators
  show hints of variations of 42 d for LSPM J2116+0234 and 37 d for GJ
  686, which we attribute to the stellar rotation periods. The orbital
  parameters of the planets are modeled with Keplerian fits together
  with correlated noise from the stellar activity. A mini-Neptune with a
  minimum mass of 11.8 M<SUB>⊕</SUB> orbits LSPM J2116+0234 producing a
  RV semi-amplitude of 6.19 m s<SUP>-1</SUP>, while a super-Earth of mass
  6.6 M<SUB>⊕</SUB> orbits GJ 686 and produces a RV semi-amplitude of
  3.0 m s<SUP>-1</SUP>. Both LSPM J2116+0234 and GJ 686 have planetary
  companions populating the regime of exoplanets with masses lower
  than 15 M<SUB>⊕</SUB> and orbital periods &lt;20 d. <P />Table
  A.1 and A.2 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A116">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A116</A>

Title: VizieR Online Data Catalog: Photometry of Kepler-82b and c
    transits (Freudenthal+, 2019)
Authors: Freudenthal, J.; von Essen, C.; Ofir, A.; Dreizler, S.; Agol,
   E.; Wedemeyer, S.; Morris, B. M.; Becker, A. C.; Deeg, H. J.; Hoyer,
   S.; Mallonn, M.; Poppenhaeger, K.; Herrero, E.; Ribas, I.; Boumis,
   P.; Liakos, A.
Bibcode: 2019yCat..36280108F
Altcode:
  All our observations were carried out using R-band filter. We provide
  the differential photometry with varying reference stars for each
  observation together with the used detrending components. We measured
  one Kepler-82b and two Kepler-82c transits in three observations
  between 2014 and 2018. <P />(4 data files).

Title: The CARMENES search for exoplanets around M dwarfs. Two
    temperate Earth-mass planet candidates around Teegarden's Star
Authors: Zechmeister, M.; Dreizler, S.; Ribas, I.; Reiners, A.;
   Caballero, J. A.; Bauer, F. F.; Béjar, V. J. S.; González-Cuesta,
   L.; Herrero, E.; Lalitha, S.; López-González, M. J.; Luque, R.;
   Morales, J. C.; Pallé, E.; Rodríguez, E.; Rodríguez López, C.;
   Tal-Or, L.; Anglada-Escudé, G.; Quirrenbach, A.; Amado, P. J.; Abril,
   M.; Aceituno, F. J.; Aceituno, J.; Alonso-Floriano, F. J.; Ammler-von
   Eiff, M.; Antona Jiménez, R.; Anwand-Heerwart, H.; Arroyo-Torres,
   B.; Azzaro, M.; Baroch, D.; Barrado, D.; Becerril, S.; Benítez,
   D.; Berdiñas, Z. M.; Bergond, G.; Bluhm, P.; Brinkmöller, M.;
   del Burgo, C.; Calvo Ortega, R.; Cano, J.; Cardona Guillén, C.;
   Carro, J.; Cárdenas Vázquez, M. C.; Casal, E.; Casasayas-Barris,
   N.; Casanova, V.; Chaturvedi, P.; Cifuentes, C.; Claret, A.; Colomé,
   J.; Cortés-Contreras, M.; Czesla, S.; Díez-Alonso, E.; Dorda, R.;
   Fernández, M.; Fernández-Martín, A.; Fuhrmeister, B.; Fukui, A.;
   Galadí-Enríquez, D.; Gallardo Cava, I.; Garcia de la Fuente, J.;
   Garcia-Piquer, A.; García Vargas, M. L.; Gesa, L.; Góngora Rueda, J.;
   González-Álvarez, E.; González Hernández, J. I.; González-Peinado,
   R.; Grözinger, U.; Guàrdia, J.; Guijarro, A.; de Guindos, E.;
   Hatzes, A. P.; Hauschildt, P. H.; Hedrosa, R. P.; Helmling, J.;
   Henning, T.; Hermelo, I.; Hernández Arabi, R.; Hernández Castaño,
   L.; Hernández Otero, F.; Hintz, D.; Huke, P.; Huber, A.; Jeffers,
   S. V.; Johnson, E. N.; de Juan, E.; Kaminski, A.; Kemmer, J.; Kim,
   M.; Klahr, H.; Klein, R.; Klüter, J.; Klutsch, A.; Kossakowski, D.;
   Kürster, M.; Labarga, F.; Lafarga, M.; Llamas, M.; Lampón, M.; Lara,
   L. M.; Launhardt, R.; Lázaro, F. J.; Lodieu, N.; López del Fresno,
   M.; López-Puertas, M.; López Salas, J. F.; López-Santiago, J.;
   Magán Madinabeitia, H.; Mall, U.; Mancini, L.; Mandel, H.; Marfil,
   E.; Marín Molina, J. A.; Maroto Fernández, D.; Martín, E. L.;
   Martín-Fernández, P.; Martín-Ruiz, S.; Marvin, C. J.; Mirabet,
   E.; Montañés-Rodríguez, P.; Montes, D.; Moreno-Raya, M. E.;
   Nagel, E.; Naranjo, V.; Narita, N.; Nortmann, L.; Nowak, G.; Ofir,
   A.; Oshagh, M.; Panduro, J.; Parviainen, H.; Pascual, J.; Passegger,
   V. M.; Pavlov, A.; Pedraz, S.; Pérez-Calpena, A.; Pérez Medialdea,
   D.; Perger, M.; Perryman, M. A. C.; Rabaza, O.; Ramón Ballesta, A.;
   Rebolo, R.; Redondo, P.; Reffert, S.; Reinhardt, S.; Rhode, P.; Rix,
   H. -W.; Rodler, F.; Rodríguez Trinidad, A.; Rosich, A.; Sadegi, S.;
   Sánchez-Blanco, E.; Sánchez Carrasco, M. A.; Sánchez-López, A.;
   Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schäfer, S.; Schmitt,
   J. H. M. M.; Schöfer, P.; Schweitzer, A.; Seifert, W.; Shulyak, D.;
   Solano, E.; Sota, A.; Stahl, O.; Stock, S.; Strachan, J. B. P.; Stuber,
   T.; Stürmer, J.; Suárez, J. C.; Tabernero, H. M.; Tala Pinto, M.;
   Trifonov, T.; Veredas, G.; Vico Linares, J. I.; Vilardell, F.; Wagner,
   K.; Wolthoff, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2019A&A...627A..49Z
Altcode: 2019arXiv190607196Z
  Context. Teegarden's Star is the brightest and one of the nearest
  ultra-cool dwarfs in the solar neighbourhood. For its late spectral
  type (M7.0 V), the star shows relatively little activity and is
  a prime target for near-infrared radial velocity surveys such as
  CARMENES. <BR /> Aims: As part of the CARMENES search for exoplanets
  around M dwarfs, we obtained more than 200 radial-velocity measurements
  of Teegarden's Star and analysed them for planetary signals. <BR />
  Methods: We find periodic variability in the radial velocities of
  Teegarden's Star. We also studied photometric measurements to rule
  out stellar brightness variations mimicking planetary signals. <BR />
  Results: We find evidence for two planet candidates, each with 1.1
  M<SUB>⊕</SUB> minimum mass, orbiting at periods of 4.91 and 11.4 d,
  respectively. No evidence for planetary transits could be found in
  archival and follow-up photometry. Small photometric variability is
  suggestive of slow rotation and old age. <BR /> Conclusions: The two
  planets are among the lowest-mass planets discovered so far, and they
  are the first Earth-mass planets around an ultra-cool dwarf for which
  the masses have been determined using radial velocities. <P />Tables
  D.1 and D.2 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A49">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A49</A>

Title: Magnetic fields in M dwarfs from the CARMENES survey
Authors: Shulyak, D.; Reiners, A.; Nagel, E.; Tal-Or, L.; Caballero,
   J. A.; Zechmeister, M.; Béjar, V. J. S.; Cortés-Contreras, M.;
   Martin, E. L.; Kaminski, A.; Ribas, I.; Quirrenbach, A.; Amado, P. J.;
   Anglada-Escudé, G.; Bauer, F. F.; Dreizler, S.; Guenther, E. W.;
   Henning, T.; Jeffers, S. V.; Kürster, M.; Lafarga, M.; Montes, D.;
   Morales, J. C.; Pedraz, S.
Bibcode: 2019A&A...626A..86S
Altcode: 2019arXiv190412762S
  Context. M dwarfs are known to generate the strongest magnetic fields
  among main-sequence stars with convective envelopes, but we are still
  lacking a consistent picture of the link between the magnetic fields
  and underlying dynamo mechanisms, rotation, and activity. <BR /> Aims:
  In this work we aim to measure magnetic fields from the high-resolution
  near-infrared spectra taken with the CARMENES radial-velocity planet
  survey in a sample of 29 active M dwarfs and compare our results
  against stellar parameters. <BR /> Methods: We used the state-of-the-art
  radiative transfer code to measure total magnetic flux densities from
  the Zeeman broadening of spectral lines and filling factors. <BR />
  Results: We detect strong kG magnetic fields in all our targets. In
  16 stars the magnetic fields were measured for the first time. Our
  measurements are consistent with the magnetic field saturation in stars
  with rotation periods P &lt; 4 d. The analysis of the magnetic filling
  factors reveal two different patterns of either very smooth distribution
  or a more patchy one, which can be connected to the dynamo state of
  the stars and/or stellar mass. <BR /> Conclusions: Our measurements
  extend the list of M dwarfs with strong surface magnetic fields. They
  also allow us to better constrain the interplay between the magnetic
  energy, stellar rotation, and underlying dynamo action. The high
  spectral resolution and observations at near-infrared wavelengths are
  the beneficial capabilities of the CARMENES instrument that allow us
  to address important questions about the stellar magnetism.

Title: VizieR Online Data Catalog: CARMENES stars multi wavelength
    measurements (Passegger+, 2019)
Authors: Passegger, V. M.; Schweitzer, A.; Shulyak, D.; Nagel, E.;
   Hauschildt, P. H.; Reiners, A.; Amado, P. J.; Caballero, J. A.;
   Cortes-Contreras, M.; Dominguez-Fernandez, A. J.; Quirrenbach,
   A.; Ribas, I.; Azarro, M.; Anglada-Escude, G.; Bauer, F. F.; Bejar,
   V. J. S.; Dreizler, S.; Guenther, E. W.; Henning, T.; Jeffers, S. V.;
   Kaminski, A.; Kuerster, M.; Lafarga, M.; Martin, E. L.; Montes, D.;
   Morales, J. C.; Schmidt, J. H. M. M.; Zechmeister, M.
Bibcode: 2019yCat..36270161P
Altcode:
  We present basic photospheric parameters of 282 M dwarfs within
  the CARMENES survey in the visible and near-infrared wavelength
  ranges. In table_b1 we provide Carmencita identifier (Karmn), Simbad
  name, equatorial coordinates, spectral type, rotational velocity,
  assumed age, and an activity flag for each star in our sample. In
  table_b2 we give effective temperature, surface gravity and [Fe/H]
  for each star in different wavelength ranges (VIS+NIR, NIR, and VIS),
  together with their errors. <P />(2 data files).

Title: BlueMUSE: Project Overview and Science Cases
Authors: Richard, Johan; Bacon, Roland; Blaizot, Jérémy; Boissier,
   Samuel; Boselli, Alessandro; NicolasBouché; Brinchmann, Jarle; Castro,
   Norberto; Ciesla, Laure; Crowther, Paul; Daddi, Emanuele; Dreizler,
   Stefan; Duc, Pierre-Alain; Elbaz, David; Epinat, Benoit; Evans, Chris;
   Fossati, Matteo; Fumagalli, Michele; Garcia, Miriam; Garel, Thibault;
   Hayes, Matthew; Adamo, Angela; Herrero, Artemio; Hugot, Emmanuel;
   Humphrey, Andrew; Jablonka, Pascale; Kamann, Sebastian; Kaper, Lex;
   Kelz, Andreas; Kneib, Jean-Paul; de Koter, Alex; Krajnović, Davor;
   Kudritzki, Rolf-Peter; Langer, Norbert; Lardo, Carmela; Leclercq,
   Floriane; Lennon, Danny; Mahler, Guillaume; Martins, Fabrice; Massey,
   Richard; Mitchell, Peter; Monreal-Ibero, Ana; Najarro, Paco; Opitom,
   Cyrielle; Papaderos, Polychronis; Péroux, Céline; Revaz, Yves; Roth,
   Martin M.; Rousselot, Philippe; Sander, Andreas; Simmonds Wagemann,
   Charlotte; Smail, Ian; Swinbank, Anthony Mark; Tramper, Frank; Urrutia,
   Tanya; Verhamme, Anne; Vink, Jorick; Walsh, Jeremy; Weilbacher, Peter;
   Wendt, Martin; Wisotzki, Lutz; Yang, Bin
Bibcode: 2019arXiv190601657R
Altcode:
  We present the concept of BlueMUSE, a blue-optimised, medium spectral
  resolution, panoramic integral field spectrograph based on the MUSE
  concept and proposed for the Very Large Telescope. With an optimised
  transmission down to 350 nm, a larger FoV (1.4 x 1.4 arcmin$^2$) and a
  higher spectral resolution compared to MUSE, BlueMUSE will open up a
  new range of galactic and extragalactic science cases allowed by its
  specific capabilities, beyond those possible with MUSE. For example
  a survey of massive stars in our galaxy and the Local Group will
  increase the known population of massive stars by a factor $&gt;$100,
  to answer key questions about their evolution. Deep field observations
  with BlueMUSE will also significantly increase samples of Lyman-alpha
  emitters, spanning the era of Cosmic Noon. This will revolutionise
  the study of the distant Universe: allowing the intergalactic medium
  to be detected unambiguously in emission, enabling the study of the
  exchange of baryons between galaxies and their surroundings. By 2030,
  at a time when the focus of most of the new large facilities (ELT,
  JWST) will be on the infra-red, BlueMUSE will be a unique facility,
  outperforming any ELT instrument in the Blue/UV. It will have a strong
  synergy with ELT, JWST as well as ALMA, SKA, Euclid and Athena.

Title: VizieR Online Data Catalog: LSPM J2116+0234 and GJ 686 radial
    velocities (Lalitha+, 2019)
Authors: Lalitha, S.; Baroch, D.; Morales, J. C.; Passegger, V. M.;
   Bauer, F. F.; Cardona Guillen, C.; Dreizler, S.; Oshagh, M.; Reiners,
   A.; Ribas, I.; Caballero, J. A.; Quirrenbach, A.; Amado, P. J.;
   Bejar, V. J. S.; Colome, J.; Cortes-Contreras, M.; Galadi-Enriquez,
   D.; Gonzalez-Cuesta, L.; Guenther, E. W.; Hagen, H. -J.; Henning, T.;
   Herrero, E.; Husser, T. -O.; Jeffers, S. V.; Kaminski, A.; Kuerster,
   M.; Lafarga, M.; Lodieu, N.; Lopez-Gonzalez, M. J.; Montes, D.;
   Perger, M.; Rosich, A.; Rodriguez, E.; Rodriguez-Lopez, C.; Schmitt,
   J. H. M. M.; Tal-Or, L.; Zechmeister, M.
Bibcode: 2019yCat..36270116L
Altcode:
  We analysed radial velocity data from the CARMENES NIR and VIS channels
  for LSPM J2116+0234, and from CARMENES VIS channel, HARPS and HIRES for
  GJ 686. All the RVs are corrected for barycentric motion and secular
  acceleration. The CARMENES measurements were taken in the context
  of the CARMENES search for exoplanets around M dwarfs. The CARMENES
  instrument consists of two channels: the VIS channel obtains spectra
  at a resolution of R=94600 in the wavelength range 520-960nm, while
  the NIR channel yields spectra of R=80400 covering 960-1710nm. Both
  channels are calibrated in wavelength with hollow-cathode lamps
  and use temperature- and pressure-stabilized Fabry-Perot etalons
  to interpolate the wavelength solution and simultaneously monitor
  the spectrograph drift during nightly operations (Bauer et al.,
  2015A&amp;A...581A.117B). <P />(2 data files).

Title: Discovery of an old nova remnant in the Galactic globular
    cluster M 22
Authors: Göttgens, Fabian; Weilbacher, Peter M.; Roth, Martin M.;
   Dreizler, Stefan; Giesers, Benjamin; Husser, Tim-Oliver; Kamann,
   Sebastian; Brinchmann, Jarle; Kollatschny, Wolfram; Monreal-Ibero,
   Ana; Schmidt, Kasper B.; Wendt, Martin; Wisotzki, Lutz; Bacon, Roland
Bibcode: 2019A&A...626A..69G
Altcode: 2019arXiv190411515G
  A nova is a cataclysmic event on the surface of a white dwarf in a
  binary system that increases the overall brightness by several orders
  of magnitude. Although binary systems with a white dwarf are expected
  to be overabundant in globular clusters compared with in the Galaxy,
  only two novae from Galactic globular clusters have been observed. We
  present the discovery of an emission nebula in the Galactic globular
  cluster M 22 (NGC 6656) in observations made with the integral-field
  spectrograph MUSE. We extracted the spectrum of the nebula and used
  the radial velocity determined from the emission lines to confirm
  that the nebula is part of NGC 6656. Emission-line ratios were used
  to determine the electron temperature and density. It is estimated
  to have a mass of 1-17 × 10<SUP>-5</SUP>M<SUB>⊙</SUB>. This mass
  and the emission-line ratios indicate that the nebula is a nova
  remnant. Its position coincides with the reported location of a
  "guest star", an ancient Chinese term for transients, observed
  in May 48 BCE. With this discovery, this nova may be one of the
  oldest confirmed extra-solar events recorded in human history. <P
  />Datacubes are also available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/626/A69">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/626/A69</A>

Title: The CARMENES search for exoplanets around M dwarfs. Different
    roads to radii and masses of the target stars
Authors: Schweitzer, A.; Passegger, V. M.; Cifuentes, C.; Béjar,
   V. J. S.; Cortés-Contreras, M.; Caballero, J. A.; del Burgo,
   C.; Czesla, S.; Kürster, M.; Montes, D.; Zapatero Osorio, M. R.;
   Ribas, I.; Reiners, A.; Quirrenbach, A.; Amado, P. J.; Aceituno, J.;
   Anglada-Escudé, G.; Bauer, F. F.; Dreizler, S.; Jeffers, S. V.;
   Guenther, E. W.; Henning, T.; Kaminski, A.; Lafarga, M.; Marfil,
   E.; Morales, J. C.; Schmitt, J. H. M. M.; Seifert, W.; Solano, E.;
   Tabernero, H. M.; Zechmeister, M.
Bibcode: 2019A&A...625A..68S
Altcode: 2019arXiv190403231S
  <BR /> Aims: We determine the radii and masses of 293 nearby, bright M
  dwarfs of the CARMENES survey. This is the first time that such a large
  and homogeneous high-resolution (R &gt; 80 000) spectroscopic survey
  has been used to derive these fundamental stellar parameters. <BR
  /> Methods: We derived the radii using Stefan-Boltzmann's law. We
  obtained the required effective temperatures T<SUB>eff</SUB> from
  a spectral analysis and we obtained the required luminosities L
  from integrated broadband photometry together with the Gaia DR2
  parallaxes. The mass was then determined using a mass-radius relation
  that we derived from eclipsing binaries known in the literature. We
  compared this method with three other methods: (1) We calculated
  the mass from the radius and the surface gravity log g, which was
  obtained from the same spectral analysis as T<SUB>eff</SUB>. (2) We
  used a widely used infrared mass-magnitude relation. (3) We used a
  Bayesian approach to infer stellar parameters from the comparison of
  the absolute magnitudes and colors of our targets with evolutionary
  models. <BR /> Results: Between spectral types M0 V and M7 V our radii
  cover the range 0.1 R<SUB>⊙</SUB> &lt; R &lt; 0.6 R<SUB>⊙</SUB>
  with an error of 2-3% and our masses cover 0.09 ℳ<SUB>⊙</SUB>
  &lt; ℳ&lt; 0.6ℳ<SUB>⊙</SUB> with an error of 3-5%. We find
  good agreement between the masses determined with these different
  methods for most of our targets. Only the masses of very young
  objects show discrepancies. This can be well explained with the
  assumptions that we used for our methods. <P />Table B.1 (stellar
  parameters) is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/625/A68">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/625/A68</A>

Title: VizieR Online Data Catalog: Radii and masses of the CARMENES
    targets (Schweitzer+, 2019)
Authors: Schweitzer, A.; Passegger, V. M.; Cifuentes, C.; Bejar,
   V. J. S.; Cortes-Contreras, M.; Caballero, J. A.; Del Burgo, C.;
   Czesla, S.; Kuerster, M.; Montes, D.; Zapatero Osorio, M. R.;
   Ribas, I.; Reiners, A.; Quirrenbach, A.; Amado, P. J.; Aceituno,
   J.; Anglada-Escude, G.; Bauer, F. F.; Dreizler, S.; Jeffers, S. V.;
   Guenther, E. W.; Henning, T.; Kaminski, A.; Lafarga, M.; Marfil,
   E.; Morales, J. C.; Schmitt, J. H. M. M.; Seifert, W.; Solano, E.;
   Tabernero, H. M.; Zechmeister, M.
Bibcode: 2019yCat..36250068S
Altcode:
  Table B1 contains the stellar parameters of our sample. The
  sample consists of 293 nearby, bright M dwarfs with no known close
  companions. Their metallicities spread around solar metallicity. Most
  stars are inactive or mildly active and older than a few hundred million
  years. However, known active or young stars are also included although
  most of the analyses assume inactive main sequence stars. All parameters
  are determined by us except where noted otherwise. <P />(1 data file).

Title: VizieR Online Data Catalog: An old nova remnant in M22
    (Goettgens+, 2019)
Authors: Goettgens, F.; Weilbacher, P. M.; Roth, M. M.; Dreizler, S.;
   Giesers, B.; Husser, T. -O.; Kamann, S.; Brinchmann, J.; Kollatschny,
   W.; Monreal-Ibero, A.; Schmidt, K. B.; Wendt, M.; Wisotzki, L.;
   Bacon, R.
Bibcode: 2019yCat..36260069G
Altcode:
  We release the 3D datacube of the nova remnant in M22. It was combined
  from data of seven MUSE observations without adaptive optics (see
  Table 1 in the paper for details). <P />We also release the spectrum
  extracted from this datacube as displayed in Fig. 2 in the paper
  (labelled 'observed' in this figure). <P />(2 data files).

Title: Gliese 49: activity evolution and detection of a super-Earth. A
    HADES and CARMENES collaboration
Authors: Perger, M.; Scandariato, G.; Ribas, I.; Morales, J. C.;
   Affer, L.; Azzaro, M.; Amado, P. J.; Anglada-Escudé, G.; Baroch,
   D.; Barrado, D.; Bauer, F. F.; Béjar, V. J. S.; Caballero, J. A.;
   Cortés-Contreras, M.; Damasso, M.; Dreizler, S.; González-Cuesta,
   L.; González Hernández, J. I.; Guenther, E. W.; Henning, T.;
   Herrero, E.; Jeffers, S. V.; Kaminski, A.; Kürster, M.; Lafarga,
   M.; Leto, G.; López-González, M. J.; Maldonado, J.; Micela, G.;
   Montes, D.; Pinamonti, M.; Quirrenbach, A.; Rebolo, R.; Reiners, A.;
   Rodríguez, E.; Rodríguez-López, C.; Schmitt, J. H. M. M.; Sozzetti,
   A.; Suárez Mascareño, A.; Toledo-Padrón, B.; Zanmar Sánchez, R.;
   Zapatero Osorio, M. R.; Zechmeister, M.
Bibcode: 2019A&A...624A.123P
Altcode: 2019arXiv190304808P
  Context. Small planets around low-mass stars often show orbital periods
  in a range that corresponds to the temperate zones of their host stars
  which are therefore of prime interest for planet searches. Surface
  phenomena such as spots and faculae create periodic signals in radial
  velocities and in observational activity tracers in the same range,
  so they can mimic or hide true planetary signals. <BR /> Aims: We
  aim to detect Doppler signals corresponding to planetary companions,
  determine their most probable orbital configurations, and understand
  the stellar activity and its impact on different datasets. <BR />
  Methods: We analyzed 22 yr of data of the M1.5 V-type star Gl 49
  (BD+61 195) including HARPS-N and CARMENES spectrographs, complemented
  by APT2 and SNO photometry. Activity indices are calculated from the
  observed spectra, and all datasets are analyzed with periodograms and
  noise models. We investigated how the variation of stellar activity
  imprints on our datasets. We further tested the origin of the signals
  and investigate phase shifts between the different sets. To search
  for the best-fit model we maximize the likelihood function in a Markov
  chain Monte Carlo approach. <BR /> Results: As a result of this study,
  we are able to detect the super-Earth Gl 49b with a minimum mass of 5.6
  M<SUB>⊕</SUB>. It orbits its host star with a period of 13.85 d at a
  semi-major axis of 0.090 au and we calculate an equilibrium temperature
  of 350 K and a transit probability of 2.0%. The contribution from the
  spot-dominated host star to the different datasets is complex, and
  includes signals from the stellar rotation at 18.86 d, evolutionary
  timescales of activity phenomena at 40-80 d, and a long-term variation
  of at least four years. <P />Based on observations made with the Italian
  TNG, operated on the island of La Palma, Spain; the CARMENES instrument
  installed at the 3.5 m telescope of the Calar Alto Observatory,
  Spain; the robotic APT2 located at Serra La Nave on Mt. Etna, Italy;
  and the T90 telescope at Sierra Nevada Observatory, Spain.Full
  Table A.1 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/624/A123">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/624/A123</A>

Title: VizieR Online Data Catalog: Gl 49 radial velocities and
    activity indicators (Perger+, 2019)
Authors: Perger, M.; Scandariato, G.; Ribas, I.; Morales, J. C.;
   Affer, L.; Azzaro, M.; Amado, P. J.; Anglada-Escude, G.; Baroch,
   D.; Barrado, D.; Bauer, F. F.; Bejar, V. J. S.; Caballero, J. A.;
   Cortes-Contreras, M.; Damasso, M.; Dreizler, S.; Gonzalez-Cuesta,
   L.; Gonzalez Hernandez, J. I.; Guenther, E. W.; Henning, T.;
   Herrero, E.; Jeffers, S. V.; Kaminski, A.; Kuerster, M.; Lafarga,
   M.; Leto, G.; Lopez-Gonzalez, M. J.; Maldonado, J.; Micela, G.;
   Montes, D.; Pinamonti, M.; Quirrenbach, A.; Rebolo, R.; Reiners, A.;
   Rodriguez, E.; Rodriguez-Lopez, C.; Schmitt, J. H. M. M.; Sozzetti,
   A.; Suarezmascareno, A.; Toledo-Padron, B.; Zanmar Sanchez, R.;
   Zapatero Osorio, M. R.; Zechmeister, M.
Bibcode: 2019yCat..36240123P
Altcode:
  Radial velocity and activity indicator time-series data of Gl 49
  from HIRES, HARPS-N, and CARMENES instruments. <P />We obtained 137
  RVs from optical spectra of the HADES program. They were observed
  over six seasons (S1 to S6) between 3 Sep 2012 and 11 Oct 2017 with
  HARPS-N. <P />We obtained spectroscopic observations with the CARMENES
  instrument, installed since 2015 at the 3.51m telescope of the Calar
  Alto Observatory in Spain. <P />Gl 49 was also observed with the HIRES
  instrument, installed since the late 1990s at the Keck I telescope
  located in Hawaii, USA. <P />(1 data file).

Title: The CARMENES search for exoplanets around M dwarfs. Period
    search in Hα, Na I D, and Ca II IRT lines
Authors: Fuhrmeister, B.; Czesla, S.; Schmitt, J. H. M. M.; Johnson,
   E. N.; Schöfer, P.; Jeffers, S. V.; Caballero, J. A.; Zechmeister,
   M.; Reiners, A.; Ribas, I.; Amado, P. J.; Quirrenbach, A.; Bauer, F.;
   Béjar, V. J. S.; Cortés-Contreras, M.; Díez Alonso, E.; Dreizler,
   S.; Galadí-Enríquez, D.; Guenther, E. W.; Kaminski, A.; Kürster,
   M.; Lafarga, M.; Montes, D.
Bibcode: 2019A&A...623A..24F
Altcode: 2019arXiv190105173F
  We use spectra from CARMENES, the Calar Alto high-Resolution search
  for M dwarfs with Exo-earths with Near-infrared and optical Echelle
  Spectrographs, to search for periods in chromospheric indices in
  16 M0-M2 dwarfs. We measure spectral indices in the Hα, the Ca
  II infrared triplet (IRT), and the Na I D lines to study which of
  these indices are best-suited to finding rotation periods in these
  stars. Moreover, we test a number of different period-search algorithms,
  namely the string length method, the phase dispersion minimisation,
  the generalized Lomb-Scargle periodogram, and the Gaussian process
  regression with quasi-periodic kernel. We find periods in four stars
  using Hα and in five stars using the Ca II IRT, two of which have
  not been found before. Our results show that both Hα and the Ca II
  IRT lines are well suited for period searches, with the Ca II IRT
  index performing slightly better than Hα. Unfortunately, the Na I D
  lines are strongly affected by telluric airglow, and we could not find
  any rotation period using this index. Further, different definitions
  of the line indices have no major impact on the results. Comparing
  the different search methods, the string length method and the phase
  dispersion minimisation perform worst, while Gaussian process models
  produce the smallest numbers of false positives and non-detections.

Title: The CARMENES search for exoplanets around M
    dwarfs. Chromospheric modeling of M 2-3 V stars with PHOENIX
Authors: Hintz, D.; Fuhrmeister, B.; Czesla, S.; Schmitt, J. H. M. M.;
   Johnson, E. N.; Schweitzer, A.; Caballero, J. A.; Zechmeister, M.;
   Jeffers, S. V.; Reiners, A.; Ribas, I.; Amado, P. J.; Quirrenbach, A.;
   Anglada-Escudé, G.; Bauer, F. F.; Béjar, V. J. S.; Cortés-Contreras,
   M.; Dreizler, S.; Galadí-Enríquez, D.; Guenther, E. W.; Hauschildt,
   P. H.; Kaminski, A.; Kürster, M.; Lafarga, M.; López del Fresno,
   M.; Montes, D.; Morales, J. C.; Passegger, V. M.; Seifert, W.
Bibcode: 2019A&A...623A.136H
Altcode: 2019arXiv190203992H
  Chromospheric modeling of observed differences in stellar activity
  lines is imperative to fully understand the upper atmospheres of
  late-type stars. We present one-dimensional parametrized chromosphere
  models computed with the atmosphere code PHOENIX using an underlying
  photosphere of 3500 K. The aim of this work is to model chromospheric
  lines of a sample of 50 M2-3 dwarfs observed in the framework of the
  CARMENES, the Calar Alto high-Resolution search for M dwarfs with
  Exo-earths with Near-infrared and optical Echelle Spectrographs,
  exoplanet survey. The spectral comparison between observed data and
  models is performed in the chromospheric lines of Na I D<SUB>2</SUB>,
  Hα, and the bluest Ca II infrared triplet line to obtain best-fit
  models for each star in the sample. We find that for inactive stars a
  single model with a VAL C-like temperature structure is sufficient to
  describe simultaneously all three lines adequately. Active stars are
  rather modeled by a combination of an inactive and an active model, also
  giving the filling factors of inactive and active regions. Moreover, the
  fitting of linear combinations on variable stars yields relationships
  between filling factors and activity states, indicating that more
  active phases are coupled to a larger portion of active regions on
  the surface of the star.

Title: The CARMENES search for exoplanets around M dwarfs. Activity
    indicators at visible and near-infrared wavelengths
Authors: Schöfer, P.; Jeffers, S. V.; Reiners, A.; Shulyak,
   D.; Fuhrmeister, B.; Johnson, E. N.; Zechmeister, M.; Ribas, I.;
   Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Anglada-Escudé,
   G.; Bauer, F. F.; Béjar, V. J. S.; Cortés-Contreras, M.; Dreizler,
   S.; Guenther, E. W.; Kaminski, A.; Kürster, M.; Lafarga, M.; Montes,
   D.; Morales, J. C.; Pedraz, S.; Tal-Or, L.
Bibcode: 2019A&A...623A..44S
Altcode: 2019arXiv190108861S
  Context. The Calar Alto high-Resolution search for M dwarfs with
  Exo-earths with Near-infrared and optical Echelle Spectrographs
  (CARMENES) survey is searching for Earth-like planets orbiting M dwarfs
  using the radial velocity method. Studying the stellar activity of
  the target stars is important to avoid false planet detections and to
  improve our understanding of the atmospheres of late-type stars. <BR
  /> Aims: In this work we present measurements of activity indicators
  at visible and near-infrared wavelengths for 331 M dwarfs observed
  with CARMENES. Our aim is to identify the activity indicators that
  are most sensitive and easiest to measure, and the correlations among
  these indicators. We also wish to characterise their variability. <BR
  /> Methods: Using a spectral subtraction technique, we measured
  pseudo-equivalent widths of the He I D<SUB>3</SUB>, Hα, He I λ10833
  Å, and Pa β lines, the Na I D doublet, and the Ca II infrared triplet,
  which have a chromospheric component in active M dwarfs. In addition,
  we measured an index of the strength of two TiO and two VO bands,
  which are formed in the photosphere. We also searched for periodicities
  in these activity indicators for all sample stars using generalised
  Lomb-Scargle periodograms. <BR /> Results: We find that the most
  slowly rotating stars of each spectral subtype have the strongest Hα
  absorption. Hα is correlated most strongly with He I D<SUB>3</SUB>,
  whereas Na I D and the Ca II infrared triplet are also correlated
  with Hα. He I λ10833 Å and Paβ show no clear correlations with
  the other indicators. The TiO bands show an activity effect that does
  not appear in the VO bands. We find that the relative variations of
  Hα and He I D<SUB>3</SUB> are smaller for stars with higher activity
  levels, while this anti-correlation is weaker for Na I D and the Ca II
  infrared triplet, and is absent for He I λ10833 Å and Paβ. Periodic
  variation with the rotation period most commonly appears in the TiO
  bands, Hα, and in the Ca II infrared triplet. <P />The full version
  of Table A.1 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/623/A44">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/623/A44</A>

Title: The CARMENES search for exoplanets around M dwarfs. The
enigmatic planetary system GJ 4276: one eccentric planet or two
planets in a 2:1 resonance?
Authors: Nagel, E.; Czesla, S.; Schmitt, J. H. M. M.; Dreizler,
   S.; Anglada-Escudé, G.; Rodríguez, E.; Ribas, I.; Reiners, A.;
   Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Aceituno, J.; Béjar,
   V. J. S.; Cortés-Contreras, M.; González-Cuesta, L.; Guenther, E. W.;
   Henning, T.; Jeffers, S. V.; Kaminski, A.; Kürster, M.; Lafarga,
   M.; López-González, M. J.; Montes, D.; Morales, J. C.; Passegger,
   V. M.; Rodríguez-López, C.; Schweitzer, A.; Zechmeister, M.
Bibcode: 2019A&A...622A.153N
Altcode: 2019arXiv190102367N
  We report the detection of a Neptune-mass exoplanet around the M4.0
  dwarf GJ 4276 (G 232-070) based on radial velocity (RV) observations
  obtained with the CARMENES spectrograph. The RV variations of GJ
  4276 are best explained by the presence of a planetary companion that
  has a minimum mass of m<SUB>b</SUB> sin i ≈ 16 M<SUB>⊕</SUB> on a
  P<SUB>b</SUB> = 13.35 day orbit. The analysis of the activity indicators
  and spectral diagnostics exclude stellar induced RV perturbations
  and prove the planetary interpretation of the RV signal. We show
  that a circular single-planet solution can be excluded by means of
  a likelihood ratio test. Instead, we find that the RV variations can
  be explained either by an eccentric orbit or interpreted as a pair of
  planets on circular orbits near a period ratio of 2:1. Although the
  eccentric single-planet solution is slightly preferred, our statistical
  analysis indicates that none of these two scenarios can be rejected
  with high confidence using the RV time series obtained so far. Based
  on the eccentric interpretation, we find that GJ 4276 b is the most
  eccentric (e<SUB>b</SUB> = 0.37) exoplanet around an M dwarf with such
  a short orbital period known today. <P />Photometric measurements
  and Table C.1 are available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/622/A153">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/622/A153</A>

Title: VizieR Online Data Catalog: Barnard's star radial velocity
    curve (Ribas+, 2018)
Authors: Ribas, I.; Tuomi, M.; Reiners, A.; Butler, R. P.;
   Morales, J. C.; Perger, M.; Dreizler, S.; Rodriguez-Lopez, C.;
   Gonzalez Hernandez, J. I.; Rosich, A.; Feng, F.; Trifonov, T.; Vogt,
   S. S.; Caballero, J. A.; Hatzes, A.; Herrero, E.; Jeffers, S. V.;
   Lafarga, M.; Murgas, F.; Nelson, R. P.; Rodriguez, E.; Strachan,
   J. B. P.; Tal-Or, L.; Teske, J.; Toledo-Padron, B.; Zechmeister, M.;
   Quirrenbach, A.; Amado, P. J.; Azzaro, M.; Bejar, V. J. S.; Barnes,
   J. R.; Berdinas, Z. M.; Burt, J.; Coleman, G.; Cortes-Contreras, M.;
   Crane, J.; Engle, S. G.; Guinan, E. F.; Haswell, C. A.; Henning, T.;
   Holden, B.; Jenkins, J.; Jones, H. R. A.; Kaminski, A.; Kiraga, M.;
   Kurster, M.; Lee, M. H.; Lopez-Gonzalez, M. J.; Montes, D.; Morin, J.;
   Ofir, A.; Palle, E.; Rebolo, R.; Reffert, S.; Schweitzer, A.; Seifert,
   W.; Shectman, S. A.; Staab, D.; Street, R. A.; Suarez Mascareno, A.;
   Tsapras, Y.; Wang, S. X.; Anglada-Escude, G.
Bibcode: 2019yCatp038056301R
Altcode:
  An early analysis of archival radial-velocity datasets of Barnard's
  star up to 2015 indicated the presence of at least one significant
  signal, which had a period of about 230 days, but with rather poor
  sampling. To elucidate its presence and nature we undertook an intensive
  monitoring campaign with the CARMENES spectrometer, collecting precise
  radial-velocity measurements on every possible night during 2016 and
  2017. We also obtained overlapping observations with the European
  Southern Observatory (ESO) HARPS and the HARPS-N instruments. The
  combined Doppler monitoring of Barnard's star, including archival and
  newly acquired observations, resulted in 771 radial-velocity epochs
  (nightly averages), with typical individual precisions of 0.9-1.8m/s,
  obtained over a timespan of more than 20 years from seven different
  facilities, and yielded eight independent datasets. <P />(4 data files).

Title: Outliers in globular clusters: the case of 47 Tucanae
Authors: Campos, Fabiola; Pelisoli, Ingrid; Kamann, Sebastian; Husser,
   Tim-Oliver; Dreizler, Stefan; Bellini, Andrea; Robinson, Edward L.;
   Nardiello, Domenico; Piotto, Giampaolo; Oliveira, Kepler; Istrate,
   Alina; Winget, Don; Montgomery, Michael H.; Dotter, Aaron
Bibcode: 2019AAS...23341408C
Altcode:
  We constructed multicolor photometric color-magnitude diagrams of the
  globular cluster 47 Tucanae using photometry obtained with the Hubble
  Space Telescope. We identify 24 previously-unremarked objects that
  are outliers from the single-star model tracks in the color-magnitude
  diagram.Based on their proper motions, all the objects are members
  of the cluster with high probability. We show that the majority of
  the sources are likely to be binary systems. Since only two of those
  objects are possible counterparts to X-ray sources, we conclude that
  most of the binaries consist of a white dwarf and a main-sequence
  star. While three may be double-degenerate binaries. This is the
  first time multicolor photometry is employed to search for binaries
  in clusters. Extension of this work can help shed light in late stages
  of binary stellar evolution in different environments.

Title: Thorium in solar twins: implications for habitability in
    rocky planets
Authors: Botelho, R. B.; Milone, A. de C.; Meléndez, J.; Bedell,
   M.; Spina, L.; Asplund, M.; dos Santos, L.; Bean, J. L.; Ramírez,
   I.; Yong, D.; Dreizler, S.; Alves-Brito, A.; Yana Galarza, J.
Bibcode: 2019MNRAS.482.1690B
Altcode: 2018MNRAS.tmp.2659B; 2018arXiv181010413B
  We have investigated the thorium (Th) abundance in a sample of 53 thin
  disc solar twins covering a wide range of ages. These data provide
  constrains on the mantle energy budget of terrestrial planets that
  can be formed over the evolution of the Galaxy's thin disc. We have
  estimated Th abundances with an average precision of 0.025 dex (in both
  [Th/H] and [Th/Fe]) through comprehensive spectral synthesis of a Th II
  line present at 4019.1290 Å, using very high resolution (R = 115 000)
  high quality HARPS spectra obtained at the ESO La Silla Observatory. We
  have confirmed that there is a large energy budget from Th decay for
  maintaining mantle convection inside potential rocky planets around
  solar twins, from the Galactic thin disc formation until now, because
  the pristine [Th/H]<SUB>ZAMS</SUB> is super-solar on average under
  a uniform dispersion of 0.056 dex (varying from +0.037 up to +0.138
  dex based on linear fits against isochrone stellar age). Comparing to
  neodymium (Nd) and europium (Eu), two others neutron-capture elements,
  the stellar pristine abundance of Th follows Eu along the Galactic thin
  disc evolution, but it does not follow Nd, probably because neodymium
  has a significant contribution from the s-process (about 60 per cent).

Title: VizieR Online Data Catalog: Photometry &amp; RV follow-up
    observations of K2-18 (Sarkis+, 2018)
Authors: Sarkis, P.; Henning, T.; Kurster, M.; Trifonov, T.;
   Zechmeister, M.; Tal-Or, L.; Anglada-Escude, G.; Hatzes, A. P.;
   Lafarga, M.; Dreizler, S.; Ribas, I.; Caballero, J. A.; Reiners,
   A.; Mallonn, M.; Morales, J. C.; Kaminski, A.; Aceituno, J.; Amado,
   P. J.; Bejar, V. J. S.; Hagen, H. -J.; Jeffers, S.; Quirrenbach, A.;
   Launhardt, R.; Marvin, C.; Montes, D.
Bibcode: 2019yCat..51550257S
Altcode:
  We monitored the host star K2-18 for photometric variability with
  the robotic 1.2 m twin-telescope STELLA on Tenerife (Strassmeier et
  al. 2004AN....325..527S) and its wide-field imager WiFSIP. From 2017
  February until 2017 June, we obtained blocks of four exposures in
  Johnson B and four exposures in Cousins R over 33 nights. The exposure
  time was 120 s in B and 60 s in R. We monitored K2-18 between 2016
  December and 2017 June with CARMENES. CARMENES (Calar Alto search
  for M dwarfs with Exo-earths with Near-infrared and optical Echelle
  Spectrographs) is a pair of high-resolution echelle spectrographs
  (Quirrenbach et al. 2014SPIE.9147E..1FQ) mounted on the 3.5 m telescope
  of the Calar Alto Observatory (CAHA) in Spain. The VIS channel covers
  the wavelength range from 0.52 to 0.96 μm and has a spectral resolution
  R=94600 (Quirrenbach et al. 2016SPIE.9908E..12Q), with a demonstrated
  precision similar to HARPS and better than Keck/HIRES (Trifonov et
  al. 2018, J/A+A/609/A117). <P />(3 data files).

Title: CARMENES input catalogue of M dwarfs. IV. New rotation periods
    from photometric time series
Authors: Díez Alonso, E.; Caballero, J. A.; Montes, D.; de Cos Juez,
   F. J.; Dreizler, S.; Dubois, F.; Jeffers, S. V.; Lalitha, S.; Naves,
   R.; Reiners, A.; Ribas, I.; Vanaverbeke, S.; Amado, P. J.; Béjar,
   V. J. S.; Cortés-Contreras, M.; Herrero, E.; Hidalgo, D.; Kürster,
   M.; Logie, L.; Quirrenbach, A.; Rau, S.; Seifert, W.; Schöfer, P.;
   Tal-Or, L.
Bibcode: 2019A&A...621A.126D
Altcode: 2018arXiv181003338D
  <BR /> Aims: The main goal of this work is to measure rotation periods
  of the M-type dwarf stars being observed by the CARMENES exoplanet
  survey to help distinguish radial-velocity signals produced by magnetic
  activity from those produced by exoplanets. Rotation periods are also
  fundamental for a detailed study of the relation between activity and
  rotation in late-type stars. <BR /> Methods: We look for significant
  periodic signals in 622 photometric time series of 337 bright, nearby M
  dwarfs obtained by long-time baseline, automated surveys (MEarth, ASAS,
  SuperWASP, NSVS, Catalina, ASAS-SN, K2, and HATNet) and for 20 stars
  which we obtained with four 0.2-0.8 m telescopes at high geographical
  latitudes. <BR /> Results: We present 142 rotation periods (73 new) from
  0.12 d to 133 d and ten long-term activity cycles (six new) from 3.0
  a to 11.5 a. We compare our determinations with those in the existing
  literature; we investigate the distribution of P<SUB>rot</SUB> in the
  CARMENES input catalogue, the amplitude of photometric variability,
  and their relation to v sini and pEW(Hα); and we identify three
  very active stars with new rotation periods between 0.34 d and
  23.6 d. <P />Tables A.1 and A.2, and tables of the photometric
  measurements are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr/">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/621/A126">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/621/A126</A>

Title: Outliers: multicolour photometry guiding the search for
    evolved binary systems in the globular cluster 47 Tucanae
Authors: Campos, Fabíola; Pelisoli, I.; Kamann, S.; Husser, T. -O.;
   Dreizler, S.; Bellini, A.; Robinson, E. L.; Nardiello, D.; Piotto,
   G.; Kepler, S. O.; Istrate, A. G.; Winget, D. E.; Montgomery, M. H.;
   Dotter, A.
Bibcode: 2018MNRAS.481.4397C
Altcode: 2018MNRAS.tmp.2465C; 2018arXiv180907746C
  We use Hubble Space Telescope multicolour photometry of the globular
  cluster 47 Tucanae to uncover a population of 24 objects with no
  previous classification that are outliers from the single-star model
  tracks in the colour-magnitude diagram and yet are likely cluster
  members. By comparing those sources with evolutionary models and
  X-ray source catalogues, we were able to show that the majority of
  those sources are likely binary systems that do not have any X-ray
  source detected nearby, most possibly formed by a white dwarf and a
  main-sequence star and a small number of possible double-degenerate
  systems.

Title: Ground-based detection of an extended helium atmosphere in
    the Saturn-mass exoplanet WASP-69b
Authors: Nortmann, Lisa; Pallé, Enric; Salz, Michael; Sanz-Forcada,
   Jorge; Nagel, Evangelos; Alonso-Floriano, F. Javier; Czesla, Stefan;
   Yan, Fei; Chen, Guo; Snellen, Ignas A. G.; Zechmeister, Mathias;
   Schmitt, Jürgen H. M. M.; López-Puertas, Manuel; Casasayas-Barris,
   Núria; Bauer, Florian F.; Amado, Pedro J.; Caballero, José A.;
   Dreizler, Stefan; Henning, Thomas; Lampón, Manuel; Montes, David;
   Molaverdikhani, Karan; Quirrenbach, Andreas; Reiners, Ansgar; Ribas,
   Ignasi; Sánchez-López, Alejandro; Schneider, P. Christian; Zapatero
   Osorio, María R.
Bibcode: 2018Sci...362.1388N
Altcode: 2018arXiv181203119N
  Hot gas giant exoplanets can lose part of their atmosphere due
  to strong stellar irradiation, and these losses can affect their
  physical and chemical evolution. Studies of atmospheric escape
  from exoplanets have mostly relied on space-based observations of
  the hydrogen Lyman-α line in the far ultraviolet region, which is
  strongly affected by interstellar absorption. Using ground-based
  high-resolution spectroscopy, we detected excess absorption in the
  helium triplet at 1083 nanometers during the transit of the Saturn-mass
  exoplanet WASP-69b, at a signal-to-noise ratio of 18. We measured line
  blueshifts of several kilometers per second and posttransit absorption,
  which we interpret as the escape of part of the atmosphere trailing
  behind the planet in comet-like form.

Title: Detection of He I λ10830 Å absorption on HD 189733 b with
    CARMENES high-resolution transmission spectroscopy
Authors: Salz, M.; Czesla, S.; Schneider, P. C.; Nagel, E.; Schmitt,
   J. H. M. M.; Nortmann, L.; Alonso-Floriano, F. J.; López-Puertas, M.;
   Lampón, M.; Bauer, F. F.; Snellen, I. A. G.; Pallé, E.; Caballero,
   J. A.; Yan, F.; Chen, G.; Sanz-Forcada, J.; Amado, P. J.; Quirrenbach,
   A.; Ribas, I.; Reiners, A.; Béjar, V. J. S.; Casasayas-Barris, N.;
   Cortés-Contreras, M.; Dreizler, S.; Guenther, E. W.; Henning, T.;
   Jeffers, S. V.; Kaminski, A.; Kürster, M.; Lafarga, M.; Lara, L. M.;
   Molaverdikhani, K.; Montes, D.; Morales, J. C.; Sánchez-López, A.;
   Seifert, W.; Zapatero Osorio, M. R.; Zechmeister, M.
Bibcode: 2018A&A...620A..97S
Altcode: 2018arXiv181202453S
  We present three transit observations of HD 189733 b obtained with
  the high-resolution spectrograph CARMENES at Calar Alto. A strong
  absorption signal is detected in the near-infrared He I triplet at
  10830 Å in all three transits. During mid-transit, the mean absorption
  level is 0.88 ± 0.04% measured in a ±10 km s<SUP>-1</SUP> range at
  a net blueshift of - 3.5 ± 0.4 km s<SUP>-1</SUP> (10829.84-10830.57
  Å). The absorption signal exhibits radial velocities of + 6.5 ±
  3.1 km s<SUP>-1</SUP> and - 12.6 ± 1.0 km s<SUP>-1</SUP> during
  ingress and egress, respectively; all radial velocities are measured
  in the planetary rest frame. We show that stellar activity related
  pseudo-signals interfere with the planetary atmospheric absorption
  signal. They could contribute as much as 80% of the observed signal
  and might also affect the observed radial velocity signature, but
  pseudo-signals are very unlikely to explain the entire signal. The
  observed line ratio between the two unresolved and the third line
  of the He I triplet is 2.8 ± 0.2, which strongly deviates from the
  value expected for an optically thin atmospheres. When interpreted
  in terms of absorption in the planetary atmosphere, this favors a
  compact helium atmosphere with an extent of only 0.2 planetary radii
  and a substantial column density on the order of 4 × 10<SUP>12</SUP>
  cm<SUP>-2</SUP>. The observed radial velocities can be understood either
  in terms of atmospheric circulation with equatorial superrotation
  or as a sign of an asymmetric atmospheric component of evaporating
  material. We detect no clear signature of ongoing evaporation, like pre-
  or post-transit absorption, which could indicate material beyond the
  planetary Roche lobe, or radial velocities in excess of the escape
  velocity. These findings do not contradict planetary evaporation,
  but only show that the detected helium absorption in HD 189733 b does
  not trace the atmospheric layers that show pronounced escape signatures.

Title: The CARMENES search for exoplanets around M dwarfs. The warm
    super-Earths in twin orbits around the mid-type M dwarfs Ross 1020
    (GJ 3779) and LP 819-052 (GJ 1265)
Authors: Luque, R.; Nowak, G.; Pallé, E.; Kossakowski, D.; Trifonov,
   T.; Zechmeister, M.; Béjar, V. J. S.; Cardona Guillén, C.;
   Tal-Or, L.; Hidalgo, D.; Ribas, I.; Reiners, A.; Caballero, J. A.;
   Amado, P. J.; Quirrenbach, A.; Aceituno, J.; Cortés-Contreras, M.;
   Díez-Alonso, E.; Dreizler, S.; Guenther, E. W.; Henning, T.; Jeffers,
   S. V.; Kaminski, A.; Kürster, M.; Lafarga, M.; Montes, D.; Morales,
   J. C.; Passegger, V. M.; Schmitt, J. H. M. M.; Schweitzer, A.
Bibcode: 2018A&A...620A.171L
Altcode: 2018arXiv181007572L
  We announce the discovery of two planetary companions orbiting
  around the low-mass stars Ross 1020 (GJ 3779, M4.0V) and LP 819-052
  (GJ 1265, M4.5V). The discovery is based on the analysis of CARMENES
  radial velocity (RV) observations in the visual channel as part of
  its survey for exoplanets around M dwarfs. In the case of GJ 1265,
  CARMENES observations were complemented with publicly available Doppler
  measurements from HARPS. The datasets reveal two planetary companions,
  one for each star, that share very similar properties: minimum
  masses of 8.0 ± 0.5 M<SUB>⊕</SUB> and 7.4 ± 0.5 M<SUB>⊕</SUB>
  in low-eccentricity orbits with periods of 3.023 ± 0.001 d and 3.651
  ± 0.001 d for GJ 3779 b and GJ 1265 b, respectively. The periodic
  signals around 3 d found in the RV data have no counterpart in any
  spectral activity indicator. Furthermore, we collected available
  photometric data for the two host stars, which confirm that the
  additional Doppler variations found at periods of approximately 95 d
  can be attributed to the rotation of the stars. The addition of these
  planets to a mass-period diagram of known planets around M dwarfs
  suggests a bimodal distribution with a lack of short-period low-mass
  planets in the range of 2-5 M<SUB>⊕</SUB>. It also indicates that
  super-Earths (&gt;5 M<SUB>⊕</SUB>) currently detected by RV and
  transit techniques around M stars are usually found in systems dominated
  by a single planet. <P />The RV and formal uncertainties of GJ 3779
  and GJ 1265 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/620/A171">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/620/A171</A>

Title: VizieR Online Data Catalog: GJ 4276 radial velocity curve
    (Nagel+, 2019)
Authors: Nagel, E.; Czesla, S.; Schmitt, J. H. M. M.; Dreizler,
   S.; Anglada-Escude, G.; Rodriguez, E.; Ribas, I.; Reiners, A.;
   Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Aceituno, J.; Bejar,
   V. J. S.; Cortes-Contreras, M.; Gonzalez-Cuesta, L.; Guenther, E. W.;
   Henning, T.; Jeffers, S. V.; Kaminski, A.; Kuerster, M.; Lafarga, M.;
   Lopez-Gonzalez, M. J.; Montes, D.; Morales, J. C. Passegger V. M.;
   Rodriguez-Lopez, C.; Schweitzer, A.; Zechmeister, M.
Bibcode: 2018yCat..36220153N
Altcode:
  We analyzed radial velocity data from the CARMENES VIS channel. The
  RVs are corrected for barycentric motion and secular acceleration. The
  CARMENES measurements were taken in the context of the CARMENES search
  for exoplanets around M dwarfs. The CARMENES instrument consists
  of two channels: the VIS channel obtains spectra at a resolution of
  R=94600 in the wavelength range 520-960nm, while the NIR channel yields
  spectra of R=80400 covering 960-1710nm. Both channels are calibrated
  in wavelength with hollow-cathode lamps and use temperature- and
  pressure-stabilized Fabry-Perot etalons to interpolate the wavelength
  solution and simultaneously monitor the spectrograph drift during
  nightly operations (Bauer et al., 2015A&amp;A...581A.117B). <P />To
  determine the stellar rotation period, we obtained V band photometry
  with the T150 telescope located at the Sierra Nevada Observatory (SNO)
  in Spain. <P />(2 data files).

Title: The CARMENES search for exoplanets around M dwarfs. Nine new
    double-line spectroscopic binary stars
Authors: Baroch, D.; Morales, J. C.; Ribas, I.; Tal-Or, L.;
   Zechmeister, M.; Reiners, A.; Caballero, J. A.; Quirrenbach, A.;
   Amado, P. J.; Dreizler, S.; Lalitha, S.; Jeffers, S. V.; Lafarga, M.;
   Béjar, V. J. S.; Colomé, J.; Cortés-Contreras, M.; Díez-Alonso,
   E.; Galadí-Enríquez, D.; Guenther, E. W.; Hagen, H. -J.; Henning,
   T.; Herrero, E.; Kürster, M.; Montes, D.; Nagel, E.; Passegger,
   V. M.; Perger, M.; Rosich, A.; Schweitzer, A.; Seifert, W.
Bibcode: 2018A&A...619A..32B
Altcode: 2018arXiv180806895B
  Context. The CARMENES spectrograph is surveying ∼300 M dwarf stars
  in search for exoplanets. Among the target stars, spectroscopic binary
  systems have been discovered, which can be used to measure fundamental
  properties of stars. <BR /> Aims: Using spectroscopic observations, we
  determine the orbital and physical properties of nine new double-line
  spectroscopic binary systems by analysing their radial velocity
  curves. <BR /> Methods: We use two-dimensional cross-correlation
  techniques to derive the radial velocities of the targets, which are
  then employed to determine the orbital properties. Photometric data from
  the literature are also analysed to search for possible eclipses and
  to measure stellar variability, which can yield rotation periods. <BR
  /> Results: Out of the 342 stars selected for the CARMENES survey, 9
  have been found to be double-line spectroscopic binaries, with periods
  ranging from 1.13 to ∼8000 days and orbits with eccentricities up
  to 0.54. We provide empirical orbital properties and minimum masses
  for the sample of spectroscopic binaries. Absolute masses are also
  estimated from mass-luminosity calibrations, ranging between ∼0.1 and
  ∼0.6 M<SUB>⊙</SUB>. <BR /> Conclusions: These new binary systems
  increase the number of double-line M dwarf binary systems with known
  orbital parameters by 15%, and they have lower mass ratios on average.

Title: A candidate super-Earth planet orbiting near the snow line
    of Barnard's star
Authors: Ribas, I.; Tuomi, M.; Reiners, A.; Butler, R. P.; Morales,
   J. C.; Perger, M.; Dreizler, S.; Rodríguez-López, C.; González
   Hernández, J. I.; Rosich, A.; Feng, F.; Trifonov, T.; Vogt, S. S.;
   Caballero, J. A.; Hatzes, A.; Herrero, E.; Jeffers, S. V.; Lafarga, M.;
   Murgas, F.; Nelson, R. P.; Rodríguez, E.; Strachan, J. B. P.; Tal-Or,
   L.; Teske, J.; Toledo-Padrón, B.; Zechmeister, M.; Quirrenbach, A.;
   Amado, P. J.; Azzaro, M.; Béjar, V. J. S.; Barnes, J. R.; Berdiñas,
   Z. M.; Burt, J.; Coleman, G.; Cortés-Contreras, M.; Crane, J.;
   Engle, S. G.; Guinan, E. F.; Haswell, C. A.; Henning, Th.; Holden,
   B.; Jenkins, J.; Jones, H. R. A.; Kaminski, A.; Kiraga, M.; Kürster,
   M.; Lee, M. H.; López-González, M. J.; Montes, D.; Morin, J.; Ofir,
   A.; Pallé, E.; Rebolo, R.; Reffert, S.; Schweitzer, A.; Seifert,
   W.; Shectman, S. A.; Staab, D.; Street, R. A.; Suárez Mascareño,
   A.; Tsapras, Y.; Wang, S. X.; Anglada-Escudé, G.
Bibcode: 2018Natur.563..365R
Altcode: 2018arXiv181105955R
  Barnard's star is a red dwarf, and has the largest proper motion
  (apparent motion across the sky) of all known stars. At a distance of
  1.8 parsecs<SUP>1</SUP>, it is the closest single star to the Sun; only
  the three stars in the α Centauri system are closer. Barnard's star is
  also among the least magnetically active red dwarfs known<SUP>2,3</SUP>
  and has an estimated age older than the Solar System. Its properties
  make it a prime target for planetary searches; various techniques with
  different sensitivity limits have been used previously, including
  radial-velocity imaging<SUP>4-6</SUP>, astrometry<SUP>7,8</SUP> and
  direct imaging<SUP>9</SUP>, but all ultimately led to negative or null
  results. Here we combine numerous measurements from high-precision
  radial-velocity instruments, revealing the presence of a low-amplitude
  periodic signal with a period of 233 days. Independent photometric
  and spectroscopic monitoring, as well as an analysis of instrumental
  systematic effects, suggest that this signal is best explained
  as arising from a planetary companion. The candidate planet around
  Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times
  that of Earth, orbiting near its snow line (the minimum distance from
  the star at which volatile compounds could condense). The combination
  of all radial-velocity datasets spanning 20 years of measurements
  additionally reveals a long-term modulation that could arise from
  a stellar magnetic-activity cycle or from a more distant planetary
  object. Because of its proximity to the Sun, the candidate planet has
  a maximum angular separation of 220 milliarcseconds from Barnard's
  star, making it an excellent target for direct imaging and astrometric
  observations in the future.

Title: VizieR Online Data Catalog: RV variability of the K-giant γ
    Draconis (Hatzes+, 2018)
Authors: Hatzes, A. P.; Endl, M.; Cochran, W. D.; MacQueen, P. J.;
   Han, I.; Lee, B. -C.; Kim, K. -M.; Mkrtichian, D.; Dollinger, M.;
   Hartmann, M.; Karjalainen, M.; Dreizler, S.
Bibcode: 2018yCat..51550120H
Altcode:
  A total of four RV data sets were used in the analysis. The earliest
  observations were made with the coude spectrograph of the 2.1 m Otto
  Struve Telescope at McDonald Observatory. A 1200 grooves/mm grating
  was used in second order in combination with a Tektronix 512x512
  CCD. Blocking filters were used to isolate the desired order. This
  instrumental setup resulted in a spectral dispersion of 0.046 Å/pixel
  at the central wavelength of 5520 Å. An 85 μm slit provided a spectral
  resolution of 0.11 Å (resolving power R=λ/Δλ=50000). The "McD-2.7"
  data set used the Tull Spectrograph (Tull et al. 1995PASP..107..251T)
  at the Harlan J. Smith 2.7 m telescope. This instrument provided a
  nominal wavelength coverage of 3600-10000 Å at a resolving power of
  R=60000. RV measurements were also made with the Bohyunsan Observatory
  Echelle Spectrograph or BOES (Kim et al. 2006A&amp;A...454..839K)
  of the 1.8 m telescope at the BOAO in South Korea. An 80 μm fiber
  resulted in a resolving power of R=90000 with a wavelength coverage
  of 3600-10500 Å. The TLS observations of γ Dra were made as part
  of the Tautenburg Observatory Planet Search (TOPS) program using the
  high-resolution coude echelle spectrometer of the Alfred Jensch 2 m
  telescope and an iodine absorption cell placed in the optical path. The
  spectrometer is grism cross-dispersed and it has a resolving power
  R=67000 and wavelength coverage 4630-7370 Å. <P />(1 data file).

Title: VizieR Online Data Catalog: Solar Twins age-chromospheric
    activity (Lorenzo-Oliveira+, 2018))
Authors: Lorenzo-Oliveira, D.; Freitas, F.; Melendez, J.; Bedell,
   M.; Ramirez, I.; Bean, J.; Asplund, M.; Spina, L.; Dreizler, S.;
   Alves-Brito, A.; Casagrande, L.
Bibcode: 2018yCat..36190073L
Altcode:
  Our sample was selected from the 88 solar twins presented in Ramirez et
  al. (2014A&amp;A...572A..48R). From this sample, we obtained data for
  70 stars with the HARPS instrument (Mayor et al., 2003Msngr.114...20M)
  at the 3.6 m telescope at the La Silla observatory, to search for
  planets around solar twins (program 188.C-0265, Bedell et al.,
  2015A&amp;A...581A..34B; Melendez et al., 2015Msngr.161...28M,
  2017A&amp;A...597A..34M). Additional data for 12 stars were found in
  the ESO archive. <P />(2 data files).

Title: Activity induced variation in spin-orbit angles as derived
    from Rossiter-McLaughlin measurements
Authors: Oshagh, M.; Triaud, A. H. M. J.; Burdanov, A.; Figueira,
   P.; Reiners, A.; Santos, N. C.; Faria, J.; Boue, G.; Díaz, R. F.;
   Dreizler, S.; Boldt, S.; Delrez, L.; Ducrot, E.; Gillon, M.; Guzman
   Mesa, A.; Jehin, E.; Khalafinejad, S.; Kohl, S.; Serrano, L.; Udry, S.
Bibcode: 2018A&A...619A.150O
Altcode: 2018arXiv180901027O
  One of the most powerful methods used to estimate sky-projected
  spin-orbit angles of exoplanetary systems is through a spectroscopic
  transit observation known as the RossiterMcLaughlin (RM) effect. So far
  mostly single RM observations have been used to estimate the spin-orbit
  angle, and thus there have been no studies regarding the variation of
  estimated spin-orbit angle from transit to transit. Stellar activity
  can alter the shape of photometric transit light curves and in a
  similar way they can deform the RM signal. In this paper we present
  several RM observations, obtained using the HARPS spectrograph, of
  known transiting planets that all transit extremely active stars,
  and by analyzing them individually we assess the variation in the
  estimated spin-orbit angle. Our results reveal that the estimated
  spin-orbit angle can vary significantly (up to 42°) from transit
  to transit, due to variation in the configuration of stellar active
  regions over different nights. This finding is almost two times larger
  than the expected variation predicted from simulations. We could not
  identify any meaningful correlation between the variation of estimated
  spin-orbit angles and the stellar magnetic activity indicators. We
  also investigated two possible approaches to mitigate the stellar
  activity influence on RM observations. The first strategy was based
  on obtaining several RM observations and folding them to reduce the
  stellar activity noise. Our results demonstrated that this is a feasible
  and robust way to overcome this issue. The second approach is based on
  acquiring simultaneous high-precision short-cadence photometric transit
  light curves using TRAPPIST/SPECULOOS telescopes, which provide more
  information about the stellar active region's properties and allow a
  better RM modeling.

Title: The Solar Twin Planet Search. The age-chromospheric activity
    relation
Authors: Lorenzo-Oliveira, Diego; Freitas, Fabrício C.; Meléndez,
   Jorge; Bedell, Megan; Ramírez, Iván; Bean, Jacob L.; Asplund, Martin;
   Spina, Lorenzo; Dreizler, Stefan; Alves-Brito, Alan; Casagrande, Luca
Bibcode: 2018A&A...619A..73L
Altcode: 2018arXiv180608014L
  Context. It is well known that the magnetic activity of solar-type stars
  decreases with age, but it is widely debated in the literature whether
  there is a smooth decline or if there is an early sharp drop until
  1-2 Gyr that is followed by a relatively inactive constant phase. <BR
  /> Aims: We revisited the activity-age relation using time-series
  observations of a large sample of solar twins whose precise isochronal
  ages and other important physical parameters have been determined. <BR
  /> Methods: We measured the Ca II H and K activity indices using ≈9000
  HARPS spectra of 82 solar twins. In addition, the average solar activity
  was calculated through asteroids and Moon reflection spectra using
  the same instrumentation. Thus, we transformed our activity indices
  into the S Mount Wilson scale (S<SUB>MW</SUB>), recalibrated the
  Mount Wilson absolute flux and photospheric correction equations as a
  function of T<SUB>eff</SUB>, and then computed an improved bolometric
  flux normalized activity index log R'<SUB>HK</SUB> (T<SUB>eff</SUB>)
  for the entire sample. <BR /> Results: New relations between activity
  and the age of solar twins were derived by assessing the chromospheric
  age-dating limits using log R'<SUB>HK</SUB> (T<SUB>eff</SUB>). We
  measured an average solar activity of S<SUB>MW</SUB> = 0.1712 ± 0.0017
  during solar magnetic cycles 23-24 covered by HARPS observations,
  and we also inferred an average of S<SUB>MW</SUB> = 0.1694 ± 0.0025
  for cycles 10-24, anchored on a sunspot number correlation of S index
  versus. We also found a simple relation between the average and the
  dispersion of the activity levels of solar twins. This enabled us to
  predict the stellar variability effects on the age-activity diagram,
  and consequently, to estimate the chromospheric age uncertainties that
  are due to the same phenomena. The age-activity relation is still
  statistically significant up to ages around 6-7 Gyr, in agreement
  with previous works using open clusters and field stars with precise
  ages. <BR /> Conclusions: Our research confirms that Ca II H &amp;
  K lines remain a useful chromospheric evolution tracer until stars
  reach ages of at least 6-7 Gyr. We found evidence that for the most
  homogenous set of old stars, the chromospheric activity indices seem
  to continue to decrease after the solar age toward the end of the main
  sequence. Our results indicate that a significant part of the scatter
  observed in the age-activity relation of solar twins can be attributed
  to stellar cycle modulations effects. The Sun seems to have a normal
  activity level and variability for its age. <P />Based on observations
  collected at the European Organisation for Astronomical Research in
  the Southern Hemisphere under ESO programs 188.C-0265, 183.D-0729,
  292.C-5004, 097.C-0571, 092.C-0721, 093.C-0409, 072.C-0488, 183.C-0972,
  091.C-0936, 192.C-0852, 196.C-1006, 076.C-0155, 096.C-0499, 185.D-0056,
  192.C-0224, 075.C-0332, 090.C-0421, 091.C-0034, 077.C-0364, 089.C-0415,
  60.A-9036, 092.C-0832, 295.C-5035, 295.C-5031, 60.A-9700, 289.D-5015,
  096.C-0210, 086.C-0284, 088.C-0323, 0100.D-0444, and 099.C-0491.Tables
  1 and 2 are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/619/A73">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/619/A73</A>

Title: VizieR Online Data Catalog: Radial velocities of GJ 3779 and
    GJ 1265 (Luque+, 2018)
Authors: Luque, R.; Nowak, G.; Palle, E.; Kossakowski, D.; Trifonov,
   T.; Zechmeister, M.; Bejar, V. J. S.; Cardona Guillen, C.; Tal-Or, L.;
   Hidalgo, D.; Ribas, I.; Reiners, A.; Caballero, J. A.; Amado, P. J.;
   Quirrenbach, A.; Aceituno, J.; Cortes-Contreras, M.; Diez-Alonso, E.;
   Dreizler, S.; Guenther, E. W.; Henning, T.; Jeffers, S. V.; Kaminski,
   A.; Kuerster, M.; Lafarga, M.; Montes, D.; Morales, J. C.; Passegger,
   V. M.; Schmitt, J. H. M. M.; Schweitzer, A.
Bibcode: 2018yCat..36200171L
Altcode:
  We analyzed radial velocity data from the CARMENES VIS channel for GJ
  3779, and from the CARMENES VIS channel and HARPS for GJ 1265. All the
  RVs are corrected for barycentric motion and secular acceleration. The
  CARMENES measurements were taken in the context of the CARMENES search
  for exoplanets around M dwarfs. The CARMENES instrument consists of two
  channels: the VIS channel obtains spectra at a resolution of R=94600 in
  the wavelength range 520-960nm, while the NIR channel yields spectra of
  R=80400 covering 960-1710nm. Both channels are calibrated in wavelength
  with hollow-cathode lamps and use temperature- and pressure-stabilized
  Fabry-Perot etalons to interpolate the wavelength solution and
  simultaneously monitor the spectrograph drift during nightly operations
  (Bauer et al., 2015A&amp;A...581A.117B). <P />(2 data files).

Title: Spitzer's Search for Proxima Centauri b Transits
Authors: Harrington, Joseph; Jenkins, James; Challener, Ryan C.;
   Kurtovic, Nicolás T.; Ramirez, Ricardo; Peña Zamudio, José;
   McIntyre, Kathleen J.; Himes, Michael D.; Rodríguez, Eloy;
   Anglada-Escudé, Guillem; Dreizler, Stefan; Ofir, Aviv; Ribas,
   Ignasi; Rojo, Patricio; Kipping, David; Butler, R. Paul; Amado,
   Pedro J.; Rodríguez-López, Cristina; Kempton, Eliza M.; Palle,
   Enric; Murgas, Felipe
Bibcode: 2018DPS....5040509H
Altcode:
  Proxima Centauri, the nearest star to the sun, hosts a habitable-zone
  planet (Anglada-Escude' et al. 2016 Nature 536, 437). Several teams
  have sought Proxima b's transits using ground-based photometry,
  and have reported tentative transit detections (Liu et al. 2018
  AJ 155, 12; Blank et al. 2018 AJ 155, 228; others). Proxima, a
  modest-sized M-dwarf star, flares at the 0.5% level (the predicted
  Proxima b transit depth) 63 times per day, according to our team's
  prior analysis of optical photometry from the Microvariability and
  Oscillations of STars spacecraft (Davenport et al. 2016 ApJL 829,
  L31). This dramatically limits optical precision. However, the effect
  of flares is much reduced in the infrared. We observed the system
  with the Spitzer Space Telescope's Infrared Array Camera in November
  2016. Our first observation was a 48-hour stare at 4.5 um. It was
  centered on the predicted transit and covered the 99% credible region
  for the transit time, based on the discovery radial-velocity (RV)
  data. Despite a transit-depth precision of 0.01% for a 1 hour transit,
  we did not detect the predicted 0.5% transit. There was structure in
  the light curve, including some asymmetric transit-like features,
  that led us to conduct follow-up observations in May, June, July,
  and November 2017. None of these observations contained detections,
  once we accounted for a new manifestation of systematics due to
  spacecraft vibration. Our improved methods for identifying and partly
  removing this effect is the topic of the next presentation. This work
  is based on observations made with the Spitzer Space Telescope, which
  is operated by the Jet Propulsion Laboratory, California Institute of
  Technology under a contract with NASA. We acknowledge support from:
  NASA Planetary Atmospheres Program grant NNX12AI69G, NASA Astrophysics
  Data Analysis Program grant NNX13AF38G. CATA-Basal/Chile PB06 Conicyt
  and Fondecyt/Chile project #1161218 (JSJ). Spanish MINECO programs
  AYA2016-79245-C03-03-P (PJA, CRL, and ER) and ESP2017-87676-C05-02-R
  (ER).

Title: The CARMENES search for exoplanets around M dwarfs. A
    Neptune-mass planet traversing the habitable zone around HD 180617
Authors: Kaminski, A.; Trifonov, T.; Caballero, J. A.; Quirrenbach,
   A.; Ribas, I.; Reiners, A.; Amado, P. J.; Zechmeister, M.; Dreizler,
   S.; Perger, M.; Tal-Or, L.; Bonfils, X.; Mayor, M.; Astudillo-Defru,
   N.; Bauer, F. F.; Béjar, V. J. S.; Cifuentes, C.; Colomé, J.;
   Cortés-Contreras, M.; Delfosse, X.; Díez-Alonso, E.; Forveille, T.;
   Guenther, E. W.; Hatzes, A. P.; Henning, Th.; Jeffers, S. V.; Kürster,
   M.; Lafarga, M.; Luque, R.; Mandel, H.; Montes, D.; Morales, J. C.;
   Passegger, V. M.; Pedraz, S.; Reffert, S.; Sadegi, S.; Schweitzer,
   A.; Seifert, W.; Stahl, O.; Udry, S.
Bibcode: 2018A&A...618A.115K
Altcode: 2018arXiv180801183K
  Despite their activity, low-mass stars are of particular importance
  for the search of exoplanets by the means of Doppler spectroscopy,
  as planets with lower masses become detectable. We report on the
  discovery of a planetary companion around HD 180617, a bright (J =
  5.58 mag), low-mass (M = 0.45M<SUB>⊙</SUB>) star of spectral type
  M2.5 V. The star, located at a distance of 5.9 pc, is the primary of
  the high proper motion binary system containing vB 10, a star with
  one of the lowest masses known in most of the twentieth century. Our
  analysis is based on new radial velocity (RV) measurements made at
  red-optical wavelengths provided by the high-precision spectrograph
  CARMENES, which was designed to carry out a survey for Earth-like
  planets around M dwarfs. The available CARMENES data are augmented
  by archival Doppler measurements from HIRES and HARPS. Altogether,
  the RVs span more than 16 yr. The modeling of the RV variations,
  with a semi-amplitude of K = 2.85<SUB>-0.25</SUB><SUP>+0.16</SUP>
  m s<SUP>-1</SUP>, yields a Neptune-like planet with a minimum
  mass of 12.2<SUB>-1.4</SUB><SUP>+1.0</SUP> M<SUB>⊕</SUB> on a
  105.90<SUB>-0.10</SUB><SUP>+0.09</SUP> d circumprimary orbit, which
  is partly located in the host star's habitable zone. The analysis of
  time series of common activity indicators does not show any dependence
  on the detected RV signal. The discovery of HD 180617 b not only adds
  information to a currently hardly filled region of the mass-period
  diagram of exoplanets around M dwarfs, but the investigated system
  becomes the third known binary consisting of M dwarfs and hosting
  an exoplanet in an S-type configuration. Its proximity makes
  it an attractive candidate for future studies. <P />The RV data
  (Table C.1) are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A> (<A
  href="http://cdsarc.u-strasbg.fr">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A115">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A115</A>

Title: Cluster kinematics and stellar rotation in NGC 419 with MUSE
    and adaptive optics
Authors: Kamann, S.; Bastian, N.; Husser, T. -O.; Martocchia, S.;
   Usher, C.; den Brok, M.; Dreizler, S.; Kelz, A.; Krajnović, D.;
   Richard, J.; Steinmetz, M.; Weilbacher, P. M.
Bibcode: 2018MNRAS.480.1689K
Altcode: 2018MNRAS.tmp.1865K; 2018arXiv180710612K
  We present adaptive optics (AO)-assisted integral-field spectroscopy
  of the intermediate-age star cluster NGC 419 in the Small Magellanic
  Cloud. By investigating the cluster dynamics and the rotation properties
  of main-sequence turn-off (MSTO) stars, we demonstrate the power of
  AO-fed MUSE observations for this class of objects. Based on 1 049
  radial velocity measurements, we determine a dynamical cluster mass
  of 1.4± 0.2× 10^5 M_⊙ and a dynamical mass-to-light ratio of 0.67
  ± 0.08, marginally higher than simple stellar population predictions
  for a Kroupa initial mass function. A stacking analysis of spectra
  at both sides of the extended MSTO reveals significant rotational
  broadening. Our analysis further provides tentative evidence that
  red MSTO stars rotate faster than their blue counterparts. We find
  average Vsin i values of 87± 16 and 130± 22 {km s^{-1}} for blue
  and red MSTO stars, respectively. Potential systematic effects due to
  the low-spectral resolution of MUSE can reach 30 {km s^{-1}} but the
  difference in Vsin i between the populations is unlikely to be affected.

Title: Kepler Object of Interest Network. II. Photodynamical modelling
    of Kepler-9 over 8 years of transit observations
Authors: Freudenthal, J.; von Essen, C.; Dreizler, S.; Wedemeyer, S.;
   Agol, E.; Morris, B. M.; Becker, A. C.; Mallonn, M.; Hoyer, S.; Ofir,
   A.; Tal-Or, L.; Deeg, H. J.; Herrero, E.; Ribas, I.; Khalafinejad,
   S.; Hernández, J.; Rodríguez S., M. M.
Bibcode: 2018A&A...618A..41F
Altcode: 2018arXiv180700007F
  Context. The Kepler Object of Interest Network (KOINet) is a multi-site
  network of telescopes around the globe organised to follow up transiting
  planet-candidate Kepler objects of interest (KOIs) with large transit
  timing variations (TTVs). Its main goal is to complete their TTV
  curves, as the Kepler telescope no longer observes the original
  Kepler field. <BR /> Aims: Combining Kepler and new ground-based
  transit data we improve the modelling of these systems. To this end,
  we have developed a photodynamical model, and we demonstrate its
  performance using the Kepler-9 system as an example. <BR /> Methods:
  Our comprehensive analysis combines the numerical integration of the
  system's dynamics over the time span of the observations along with
  the transit light curve model. This provides a coherent description of
  all observations simultaneously. This model is coupled with a Markov
  chain Monte Carlo algorithm, allowing for the exploration of the
  model parameter space. <BR /> Results: Applied to the Kepler-9 long
  cadence data, short cadence data, and 13 new transit observations
  collected by KOINet between the years 2014 and 2017, our modelling
  provides well constrained predictions for the next transits and the
  system's parameters. We have determined the densities of the planets
  Kepler-9b and 9c to the very precise values of ρ<SUB>b</SUB> =
  0.439 ± 0.023 g cm<SUP>-3</SUP> and ρ<SUB>c</SUB> = 0.322 ±
  0.017 g cm<SUP>-3</SUP>. Our analysis reveals that Kepler-9c will
  stop transiting in about 30 yr due to strong dynamical interactions
  between Kepler-9b and 9c, near 2:1 resonance, leading to a periodic
  change in inclination. <BR /> Conclusions: Over the next 30 years, the
  inclination of Kepler-9c (-9b) will decrease (increase) slowly. This
  should be measurable by a substantial decrease (increase) in the transit
  duration, in as soon as a few years' time. Observations that contradict
  this prediction might indicate the presence of additional objects
  in this system. If this prediction turns out to be accurate, this
  behaviour opens up a unique chance to scan the different latitudes of a
  star: high latitudes with planet c and low latitudes with planet b. <P
  />Ground-based photometry is only available at the CDS via anonymous ftp
  to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://cdsarc.u-strasbg.fr">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A41">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A41</A>

Title: MUSE crowded field 3D spectroscopy in NGC 300. I. First
    results from central fields
Authors: Roth, Martin M.; Sandin, Christer; Kamann, Sebastian; Husser,
   Tim-Oliver; Weilbacher, Peter M.; Monreal-Ibero, Ana; Bacon, Roland;
   den Brok, Mark; Dreizler, Stefan; Kelz, Andreas; Marino, Raffaella
   Anna; Steinmetz, Matthias
Bibcode: 2018A&A...618A...3R
Altcode: 2018arXiv180604280R
  <BR /> Aims: As a new approach to the study of resolved stellar
  populations in nearby galaxies, our goal is to demonstrate with a pilot
  study in NGC 300 that integral field spectroscopy with high spatial
  resolution and excellent seeing conditions reaches an unprecedented
  depth in severely crowded fields. <BR /> Methods: Observations by MUSE
  with seven pointings in NGC 300 have resulted in data cubes that are
  analyzed in four ways: (1) Point spread function-fitting 3D spectroscopy
  with PampelMUSE, as already successfully pioneered in globular clusters,
  yields de-blended spectra of individually distinguishable stars,
  thus providing a complete inventory of blue and red supergiants, and
  asymptotic giant branch (AGB) stars of type M and C. The technique is
  also applicable to emission line point sources and provides samples of
  planetary nebulae (PNe) that are complete down to m<SUB>5007</SUB> =
  28. (2) Pseudo-monochromatic images, created at the wavelengths of the
  most important emission lines and corrected for continuum light with
  the P3D visualization tool, provide maps of H II regions, supernova
  remnants (SNR), and the diffuse interstellar medium (ISM) at a high
  level of sensitivity, where also faint point sources stand out and
  allow for the discovery of PNe, Wolf-Rayet (WR) stars, etc. (3) The
  use of the P3D line-fitting tool yields emission line fluxes, surface
  brightness, and kinematic information for gaseous objects, corrected
  for absorption line profiles of the underlying stellar population in
  the case of Hα. (4) Visual inspection of the data cubes by browsing
  through the row-stacked spectra image in P3D is demonstrated to be
  efficient for data mining and the discovery of background galaxies
  and unusual objects. <BR /> Results: We present a catalog of luminous
  stars, rare stars such as WR, and other emission line stars, carbon
  stars, symbiotic star candidates, PNe, H II regions, SNR, giant
  shells, peculiar diffuse and filamentary emission line objects, and
  background galaxies, along with their spectra. <BR /> Conclusions:
  The technique of crowded-field 3D spectroscopy, using the PampelMUSE
  code, is capable of deblending individual bright stars, the unresolved
  background of faint stars, gaseous nebulae, and the diffuse component
  of the ISM, resulting in unprecedented legacy value for observations
  of nearby galaxies with MUSE. <P />Based on observations obtained at
  the Very Large Telescope (VLT) of the European Southern Observatory,
  Paranal, Chile (ESO Programme ID 094.D-0116(A), 094.D-0116(B),
  095.D-0173(A)).The full version of Tables 6, 9 and the reduced dat-acube
  (FITS file) are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A3">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/618/A3</A>

Title: VizieR Online Data Catalog: NGC 300 MUSE spectroscopy for
    central fields (Roth+, 2018)
Authors: Roth, M. M.; Sandin, C.; Kamann, S.; Husser, T. -O.,
   Weilbacher, P. M.; Monreal-Ibero, A.; Bacon, R.; den Brok, M.;
   Dreizler, S.; Kelz, A.; Marino, R. A.; Steinmetz, M.
Bibcode: 2018yCat..36180003R
Altcode:
  Observations were made with the multi unit spectroscopic explorer
  instrument (MUSE), which is placed at the Nasmyth focus of the UT4 8.2m
  telescope at the Very Large Telescope observatory (VLT) of the European
  Southern Observatory (ESO) in Chile. NGC 300 was observed as part of
  guaranteed time observations of the MUSE instrument-building consortium
  during the three periods P93, P94, and P95. <P />We present a catalog
  of luminous stars, rare stars such as WR, and other emission line
  stars, carbon stars, symbiotic star candidates, PNe, HII regions, SNR,
  giant shells, peculiar diffuse and filamentary emission line objects,
  and background galaxies, along with their spectra. <P />(4 data files).

Title: The atmosphere of WASP-17b: Optical high-resolution
    transmission spectroscopy
Authors: Khalafinejad, Sara; Salz, Michael; Cubillos, Patricio E.;
   Zhou, George; von Essen, Carolina; Husser, Tim-Oliver; Bayliss,
   Daniel D. R.; López-Morales, Mercedes; Dreizler, Stefan; Schmitt,
   Jürgen H. M. M.; Lüftinger, Theresa
Bibcode: 2018A&A...618A..98K
Altcode: 2018arXiv180710621K
  High-resolution transmission spectroscopy is a method for understanding
  the chemical and physical properties of upper exoplanetary
  atmospheres. Due to large absorption cross-sections, resonance lines
  of atomic sodium D-lines (at 5889.95 and 5895.92 Å) produce large
  transmission signals. Our aim is to unveil the physical properties
  of WASP-17b through an accurate measurement of the sodium absorption
  in the transmission spectrum. We analyze 37 high-resolution spectra
  observed during a single transit of WASP-17b with the MIKE instrument
  on the 6.5 m Magellan Telescopes. We exclude stellar flaring activity
  during the observations by analyzing the temporal variations of
  H<SUB>α</SUB> and Ca II infrared triplet (IRT) lines. We then obtain
  the excess absorption light curves in wavelength bands of 0.75, 1,
  1.5, and 3 Å around the center of each sodium line (i.e., the light
  curve approach). We model the effects of differential limb-darkening,
  and the changing planetary radial velocity on the light curves. We also
  analyze the sodium absorption directly in the transmission spectrum,
  which is obtained by dividing in-transit by out-of-transit spectra
  (i.e., the division approach). We then compare our measurements with
  a radiative transfer atmospheric model. Our analysis results in a
  tentative detection of exoplanetary sodium: we measure the width and
  amplitude of the exoplanetary sodium feature to be σ<SUB>Na</SUB> =
  (0.128 ± 0.078) Å and A<SUB>Na</SUB> = (1.7 ± 0.9)% in the excess
  light curve approach and σ<SUB>Na</SUB> = (0.850 ± 0.034) Å and
  A<SUB>Na</SUB> = (1.3 ± 0.6)% in the division approach. By comparing
  our measurements with a simple atmospheric model, we retrieve an
  atmospheric temperature of 15501550 <SUB>-200</SUB><SUP>+700</SUP>
  K and radius (at 0.1 bar) of 1.81 ± 0.02 R<SUB>Jup</SUB> for WASP-17b.

Title: Improved Methods for Spitzer Systematic Identification
    and Removal
Authors: Challener, Ryan C.; Harrington, Joseph; Jenkins, James;
   Kurtovic, Nicolás T.; Ramirez, Ricardo; Peña Zamudio, José;
   McIntyre, Kathleen J.; Himes, Michael D.; Rodríguez, Eloy;
   Anglada-Escudé, Guillem; Dreizler, Stefan; Ofir, Aviv; Ribas,
   Ignasi; Rojo, Patricio; Kipping, David; Butler, R. Paul; Amado,
   Pedro J.; Rodríguez-López, Cristina; Kempton, Eliza M.; Palle,
   Enric; Murgas, Felipe
Bibcode: 2018DPS....5040510C
Altcode:
  After the discovery of Proxima Centauri b in 2016, we observed the
  system with the Spitzer Space Telescope to look for transits. We
  confirmed that the planet does not transit. However, we observed
  three asymmetric, periodic, comet-like events. Unfortunately, we now
  understand these events to be systematic effects due to telescope
  vibration, which is occasionally temporally resolved with our 0.02
  second frame time. This systematic has been previously identified as a
  spike in the number of pixels significantly contributing to photometry,
  but that metric can be misleading. We show that coherent, high-frequency
  activity in the point-spread function area, measured several ways,
  is more indicative of this systematic, and that the effect can be
  partially removed by a quadratic model dependent on point-spread
  function width. This systematic occurs at an exoplanet-signal level
  three times in our 80 hours, and more frequently at a lower level, which
  has implications for transits and eclipses of small and cool planets,
  respectively. Spitzer is operated by the Jet Propulsion Laboratory,
  California Institute of Technology, under a contract with NASA. This
  work was supported by NASA Planetary Atmospheres grant NNX12AI69G and
  NASA Astrophysics Data Analysis Program grant NNX13AF38G.

Title: VizieR Online Data Catalog: KOINet. Study of exoplanet systems
    via TTVs (von Essen+, 2018)
Authors: von Essen, C.; Ofir, A.; Dreizler, S.; Agol, E.; Freudenthal,
   J.; Hernandez, J.; Wedemeyer, S.; Parkash, V.; Deeg, H. J.; Hoyer,
   S.; Morris, B. M.; Becker, A. C.; Sun, L.; Gu, S. H.; Herrero, E.;
   Tal-Or, L.; Poppenhaeger, K.; Mallonn, M.; Albrecht, S.; Khalafinejad,
   S.; Boumis, P.; Delgado-Correal, C.; Fabrycky, D. C.; Janulis, R.;
   Lalitha, S.; Liakos, A.; Mikolaitis, S.; Moyano D'Angelo, M. L.; Sokov,
   E.; Pakstiene, E.; Popov, A.; Krushinsky, V.; Ribas, I.; Rodriguez,
   M. M. S.; Rusov, S.; Sokova, I.; Tautvaisiene, G.; Wang, X.
Bibcode: 2018yCat..36150079V
Altcode:
  All our observations were carried out using R-band filter. We
  provide the differential photometry with varying reference stars for
  each observation together with the used detrending components. We
  provide four transits of KOI-0410.01, and one transit of KOI-0902.01,
  KOI-0525.01, and KOI-0760.01, respectively. The telescope nomenclature,
  in agreement with the names of the files, is the following: <P
  />IAC0.8: IAC80 telescope (0.8m), Instituto de Astrofisica de Canarias,
  Spain. ARC3.5: Apache Point Observatory (3.5 m), USA. NOT2.5: Nordic
  Optical Telescope (2.5 m), Spain. YO2.4: Yunnan Observatories (2.4 m),
  PR China. <P />(8 data files).

Title: The Chemical Homogeneity of Sun-like Stars in the Solar
    Neighborhood
Authors: Bedell, Megan; Bean, Jacob L.; Meléndez, Jorge; Spina,
   Lorenzo; Ramírez, Ivan; Asplund, Martin; Alves-Brito, Alan; dos
   Santos, Leonardo; Dreizler, Stefan; Yong, David; Monroe, TalaWanda;
   Casagrande, Luca
Bibcode: 2018ApJ...865...68B
Altcode: 2018arXiv180202576B
  The compositions of stars are a critical diagnostic tool for many
  topics in astronomy such as the evolution of our Galaxy, the formation
  of planets, and the uniqueness of the Sun. Previous spectroscopic
  measurements indicate a large intrinsic variation in the elemental
  abundance patterns of stars with similar overall metal content. However,
  systematic errors arising from inaccuracies in stellar models are known
  to be a limiting factor in such studies, and thus it is uncertain to
  what extent the observed diversity of stellar abundance patterns is
  real. Here we report the abundances of 30 elements with precisions of 2%
  for 79 Sun-like stars within 100 pc. Systematic errors are minimized in
  this study by focusing on solar twin stars and performing a line-by-line
  differential analysis using high-resolution, high-signal-to-noise
  spectra. We resolve [X/Fe] abundance trends in galactic chemical
  evolution at precisions of 10<SUP>-3</SUP> dex Gyr<SUP>-1</SUP>
  and reveal that stars with similar ages and metallicities have
  nearly identical abundance patterns. Contrary to previous results,
  we find that the ratios of carbon-to-oxygen and magnesium-to-silicon
  in solar-metallicity stars are homogeneous to within 10% throughout
  the solar neighborhood, implying that exoplanets may exhibit much less
  compositional diversity than previously thought. Finally, we demonstrate
  that the Sun has a subtle deficiency in refractory material relative
  to &gt;80% of solar twins (at 2σ confidence), suggesting a possible
  signpost for planetary systems like our own.

Title: VizieR Online Data Catalog: CARMENES input catalogue of M
    dwarfs. IV. (Diez Alonso+ 2019)
Authors: Diez Alonso, E.; Caballero, J. A.; Montes, D.; de Cos Juez,
   F. J.; Dreizler, S.; Dubois, F.; Jeffers, S. V.; Lalitha, S.; Naves,
   R.; Reiners, A.; Ribas, I.; Vanaverbeke, S.; Amado, P. J.; Bejar,
   V. J. S.; Cortes-Contreras, M.; Herrero, E.; Hidalgo, D.; Kuerster,
   M.; Logie, L.; Quirrenbach, A.; Rau, S.; Seifert, W.; Schoefer, P.;
   Tal-Or, L.
Bibcode: 2018yCat..36210126D
Altcode:
  During guaranteed time observations (GTOs), the double-channel
  CARMENES spectrograph has so far observed a sample of 336 bright,
  nearby M dwarfs with the goal of detecting low-mass planets in their
  habitable zone with the radial-velocity method (Quirrenbach et al.,
  2015, in 18th Cambridge Workshop on Cool Stars, Stellar Systems, and
  the Sun, Proceedings of the conference held at Lowell Observatory,
  8-14 June 2014. Edited by G. van Belle and H.C. Harris., pp. 897-906;
  Reiners et al., 2018, Cat. J/A+A/612/A49). Of these, 324 were presented
  by Reiners et al. (2018, Cat. J/A+A/612/A49), three did not have enough
  CARMENES observations at the time of preparing the spectral templates
  for the study, and nine are new spectroscopic binaries (Baroch et
  al., 2018, A&amp;A, in prep, arXiv:1808.06895). Here, we investigate
  the photometric variability of these 336 M dwarfs and of G 34-23 AB
  (J01221+221AB), which Cortes-Contreras et al. (2017, Cat. J/A+A/597/A47)
  found to be a close physical binary just before GTO start. This results
  in a final sample size of 337 stars. <P />(2 data files).

Title: VizieR Online Data Catalog:  A Neptune-mass planet traversing
    the habitable zone around HD 180617 (Kaminski+, 2018)
Authors: Kaminski, A.; Trifonov, T.; Caballero, J. A.; Quirrenbach,
   A.; Ribas, I.; Reiners, A.; Amado, P. J.; Zechmeister, M.; Dreizler,
   S.; Perger, M.; Tal-Or, L.; Bonfils, X.; Mayor, M.; Astudillo-Defru,
   N.; Bauer, F. F.; Bejar, V. J. S.; Cifuentes, C.; Colome, J.;
   Cortes-Contreras, M.; Delfosse, X.; Diez-Alonso, E.; Forveille, T.;
   Guenther, E. W.; Hatzes, A. P.; Henning, Th.; Jeffers, S. V.; Kuerster,
   M.; Lafarga, M.; Luque, R.; Mandel, H.; Montes, D.; Morales, J. C.;
   Passegger, V. M.; Pedraz, S.; Reffert, S.; Sadegi, S.; Schweitzer,
   A.; Seifert, W.; Stahl, O.; Udry, S.
Bibcode: 2018yCat..36180115K
Altcode:
  We analyzed radial velocity data from the CARMENES VIS channel,
  HIRES/Keck, and HARPS. All the RVs are corrected for barycentric
  motion and secular acceleration. The CARMENES measurements were
  taken in the context of the CARMENES search for exoplanets around
  M dwarfs. The CARMENES instrument consists of two channels: the VIS
  channel obtains spectra at a resolution of R=94600 in the wavelength
  range 520-960nm, while the NIR channel yields spectra of R=80400
  covering 960-1710nm. Both channels are calibrated in wavelength with
  hollow-cathode lamps and use temperature- and pressure-stabilized
  Fabry-Perot etalons to interpolate the wavelength solution and
  simultaneously monitor the spectrograph drift during nightly operations
  (Bauer et al., 2015A&amp;A...581A.117B). <P />(1 data file).

Title: VizieR Online Data Catalog: Photometry of Kepler-9b and c
    transits (Freudenthal+, 2018)
Authors: Freudenthal, J.; von Essen, C.; Dreizler, S.; Wedemeyer, S.;
   Agol, E.; Morris, B. M.; Becker, A. C.; Mallonn, M.; Hoyer, S.; Ofir,
   A.; Tal-Or, L.; Deeg, H. J.; Herrero, E.; Ribas, I.; Khalafinejad,
   S.; Hernandez, J.; Rodriguez, S. M. M.
Bibcode: 2018yCat..36180041F
Altcode:
  All our observations were carried out using R-band filter. We provide
  the differential photometry with varying reference stars for each
  observation together with the used detrending components. We measured
  five Kepler-9b and four Kepler-9c transits in thirteen observations
  between 2014 and 2017. <P />(14 data files).

Title: VizieR Online Data Catalog: CARMENES SB2 orbital parameters
    (Baroch+, 2018)
Authors: Baroch, D.; Morales, J. C.; Ribas, I.; Tal-Or, L.;
   Zechmeister, M.; Reiners, A.; Caballero, J. A.; Quirrenbach, A.;
   Amado, P. J.; Dreizler, S.; Lalitha, S.; Jeers, S. V.; Lafarga, M.;
   Bejar, V. J. S.; Colome, J.; Cortes-Contreras, M.; Diez-Alonso, E.;
   Galadi-Enriquez, D.; Guenther, E. W.; Hagen, H. -J.; Henning, T.;
   Herrero, E.; Kuerster, M.; Montes, D.; Nagel, E.; Passegger, V. M.;
   Perger, M.; Rosich, A.; Schweitzer, A.; Seifert, W.
Bibcode: 2018yCat..36190032B
Altcode:
  These tables list the radial velocities of the SB2 binary systems
  detected with CARMENES which are used to compute their orbital and
  physical properties. Besides, Table D1 is an effort to compile all known
  M-dwarf SB2s with published orbital parameters. A total of 67 systems,
  29 of which are eclipsing, have been found. Most of the systems are
  taken from the SB9 catalogue of spectroscopic binaries (Pourbaix et
  al., 2004, Cat. B/sb9), while additional systems have been found in
  a bibliographic search. CARMENES spectroscopic binaries are included
  in this table. <P />(2 data files).

Title: The MICADO first light imager for the ELT: overview, operation,
    simulation
Authors: Davies, R.; Alves, J.; Clénet, Y.; Lang-Bardl, F.;
   Nicklas, H.; Pott, J. -U.; Ragazzoni, R.; Tolstoy, E.; Amico, P.;
   Anwand-Heerwart, H.; Barboza, S.; Barl, L.; Baudoz, P.; Bender, R.;
   Bezawada, N.; Bizenberger, P.; Boland, W.; Bonifacio, P.; Borgo, B.;
   Buey, T.; Chapron, F.; Chemla, F.; Cohen, M.; Czoske, O.; Déo, V.;
   Disseau, K.; Dreizler, S.; Dupuis, O.; Fabricius, M.; Falomo, R.;
   Fedou, P.; Förster Schreiber, N.; Garrel, V.; Geis, N.; Gemperlein,
   H.; Gendron, E.; Genzel, R.; Gillessen, S.; Glück, M.; Grupp,
   F.; Hartl, M.; Häuser, M.; Hess, H. -J.; Hofferbert, R.; Hopp, U.;
   Hörmann, V.; Hubert, Z.; Huby, E.; Huet, J. -M.; Hutterer, V.; Ives,
   D.; Janssen, A.; Jellema, W.; Kausch, W.; Kerber, F.; Kravcar, H.; Le
   Ruyet, B.; Leschinski, K.; Mandla, C.; Manhart, M.; Massari, D.; Mei,
   S.; Merlin, F.; Mohr, L.; Monna, A.; Muench, N.; Müller, F.; Musters,
   G.; Navarro, R.; Neumann, U.; Neumayer, N.; Niebsch, J.; Plattner, M.;
   Przybilla, N.; Rabien, S.; Ramlau, R.; Ramos, J.; Ramsay, S.; Rhode,
   P.; Richter, A.; Richter, J.; Rix, H. -W.; Rodeghiero, G.; Rohloff,
   R. -R.; Rosensteiner, M.; Rousset, G.; Schlichter, J.; Schubert, J.;
   Sevin, A.; Stuik, R.; Sturm, E.; Thomas, J.; Tromp, N.; Verdoes-Kleijn,
   G.; Vidal, F.; Wagner, R.; Wegner, M.; Zeilinger, W.; Ziegleder, J.;
   Ziegler, B.; Zins, G.
Bibcode: 2018SPIE10702E..1SD
Altcode: 2018arXiv180710003D
  MICADO will enable the ELT to perform diffraction limited near-infrared
  observations at first light. The instrument's capabilities focus on
  imaging (including astrometric and high contrast) as well as single
  object spectroscopy. This contribution looks at how requirements
  from the observing modes have driven the instrument design and
  functionality. Using examples from specific science cases, and making
  use of the data simulation tool, an outline is presented of what we
  can expect the instrument to achieve.

Title: CARMENES: high-resolution spectra and precise radial velocities
    in the red and infrared
Authors: Quirrenbach, A.; Amado, P. J.; Ribas, I.; Reiners, A.;
   Caballero, J. A.; Seifert, W.; Aceituno, J.; Azzaro, M.; Baroch, D.;
   Barrado, D.; Bauer, F.; Becerril, S.; Bèjar, V. J. S.; Benítez,
   D.; Brinkmöller, M.; Cardona Guillén, C.; Cifuentes, C.; Colomé,
   J.; Cortés-Contreras, M.; Czesla, S.; Dreizler, S.; Frölich, K.;
   Fuhrmeister, B.; Galadí-Enríquez, D.; González Hernández, J. I.;
   González Peinado, R.; Guenther, E. W.; de Guindos, E.; Hagen, H. -J.;
   Hatzes, A. P.; Hauschildt, P. H.; Helmling, J.; Henning, Th.; Herbort,
   O.; Hernández Castaño, L.; Herrero, E.; Hintz, D.; Jeffers, S. V.;
   Johnson, E. N.; de Juan, E.; Kaminski, A.; Klahr, H.; Kürster,
   M.; Lafarga, M.; Sairam, L.; Lampón, M.; Lara, L. M.; Launhardt,
   R.; López del Fresno, M.; López-Puertas, M.; Luque, R.; Mandel,
   H.; Marfil, E. G.; Martín, E. L.; Martín-Ruiz, S.; Mathar, R. J.;
   Montes, D.; Morales, J. C.; Nagel, E.; Nortmann, L.; Nowak, G.; Pallé,
   E.; Passegger, V. -M.; Pavlov, A.; Pedraz, S.; Pérez-Medialdea, D.;
   Perger, M.; Rebolo, R.; Reffert, S.; Rodríguez, E.; Rodríguez López,
   C.; Rosich, A.; Sabotta, S.; Sadegi, S.; Salz, M.; Sánchez-López,
   A.; Sanz-Forcada, J.; Sarkis, P.; Schäfer, S.; Schiller, J.; Schmitt,
   J. H. M. M.; Schöfer, P.; Schweitzer, A.; Shulyak, D.; Solano, E.;
   Stahl, O.; Tala Pinto, M.; Trifonov, T.; Zapatero Osorio, M. R.; Yan,
   F.; Zechmeister, M.; Abellán, F. J.; Abril, M.; Alonso-Floriano,
   F. J.; Ammler-von Eiff, M.; Anglada-Escudé, G.; Anwand-Heerwart, H.;
   Arroyo-Torres, B.; Berdiñas, Z. M.; Bergondy, G.; Blümcke, M.; del
   Burgo, C.; Cano, J.; Carro, J.; Cárdenas, M. C.; Casal, E.; Claret,
   A.; Díez-Alonso, E.; Doellinger, M.; Dorda, R.; Feiz, C.; Fernández,
   M.; Ferro, I. M.; Gaisné, G.; Gallardo, I.; Gálvez-Ortiz, M. C.;
   García-Piquer, A.; García-Vargas, M. L.; Garrido, R.; Gesa, L.;
   Gómez Galera, V.; González-Álvarez, E.; González-Cuesta, L.;
   Grohnert, S.; Grözinger, U.; Guàrdia, J.; Guijarro, A.; Hedrosa,
   R. P.; Hermann, D.; Hermelo, I.; Hernández Arabí, R.; Hernández
   Hernando, F.; Hidalgo, D.; Holgado, G.; Huber, A.; Huber, K.; Huke,
   P.; Kehr, M.; Kim, M.; Klein, R.; Klüter, J.; Klutsch, A.; Labarga,
   F.; Labiche, N.; Lamert, A.; Laun, W.; Lázaro, F. J.; Lemke, U.;
   Lenzen, R.; Llamas, M.; Lizon, J. -L.; Lodieu, N.; López González,
   M. J.; López-Morales, M.; López Salas, J. F.; López-Santiago,
   J.; Magán Madinabeitia, H.; Mall, U.; Mancini, L.; Marín Molina,
   J. A.; Martínez-Rodríguez, H.; Maroto Fernández, D.; Marvin, C. J.;
   Mirabet, E.; Moreno-Raya, M. E.; Moya, A.; Mundt, R.; Naranjo, V.;
   Panduro, J.; Pascual, J.; Pérez-Calpena, A.; Perryman, M. A. C.;
   Pluto, M.; Ramón, A.; Redondo, P.; Reinhart, S.; Rhode, P.; Rix,
   H. -W.; Rodler, F.; Rohloff, R. -R.; Sánchez-Blanco, E.; Sánchez
   Carrasco, M. A.; Sarmiento, L. F.; Schmidt, C.; Storz, C.; Strachan,
   J. B. P.; Stürmer, J.; Suárez, J. C.; Tabernero, H. M.; Tal-Or, L.;
   Tulloch, S. M.; Ulbrich, R. -G.; Veredas, G.; Vico Linares, J. L.;
   Vidal-Dasilva, M.; Vilardell, F.; Wagner, K.; Winkler, J.; Wolthoff,
   V.; Xu, W.; Zhao, Z.
Bibcode: 2018SPIE10702E..0WQ
Altcode:
  The design and construction of CARMENES has been presented at previous
  SPIE conferences. It is a next-generation radial-velocity instrument at
  the 3.5m telescope of the Calar Alto Observatory, which was built by a
  consortium of eleven Spanish and German institutions. CARMENES consists
  of two separate échelle spectrographs covering the wavelength range
  from 0.52 to 1.71μm at a spec-tral resolution of R &lt; 80,000, fed by
  fibers from the Cassegrain focus of the telescope. CARMENES saw "First
  Light" on Nov 9, 2015. During the commissioning and initial operation
  phases, we established basic performance data such as throughput and
  spectral resolution. We found that our hollow-cathode lamps are suitable
  for precise wavelength calibration, but their spectra contain a number
  of lines of neon or argon that are so bright that the lamps cannot be
  used in simultaneous exposures with stars. We have therefore adopted
  a calibration procedure that uses simultaneous star / Fabry Pérot
  etalon exposures in combination with a cross-calibration between the
  etalons and hollow-cathode lamps during daytime. With this strategy
  it has been possible to achieve 1-2 m/s precision in the visible and
  5-10 m/s precision in the near-IR; further improvements are expected
  from ongoing work on temperature control, calibration procedures
  and data reduction. Comparing the RV precision achieved in different
  wavelength bands, we find a "sweet spot" between 0.7 and 0.8μm, where
  deep TiO bands provide rich RV information in mid-M dwarfs. This is
  in contrast to our pre-survey models, which predicted comparatively
  better performance in the near-IR around 1μm, and explains in
  part why our near-IR RVs do not reach the same precision level as
  those taken with the visible spectrograph. We are now conducting a
  large survey of 340 nearby M dwarfs (with an average distance of only
  12pc), with the goal of finding terrestrial planets in their habitable
  zones. We have detected the signatures of several previously known or
  suspected planets and also discovered several new planets. We find
  that the radial velocity periodograms of many M dwarfs show several
  significant peaks. The development of robust methods to distinguish
  planet signatures from activity-induced radial velocity jitter is
  therefore among our priorities. Due to its large wavelength coverage,
  the CARMENES survey is generating a unique data set for studies of M
  star atmospheres, rotation, and activity. The spectra cover important
  diagnostic lines for activity (H alpha, Na I D1 and D2, and the Ca II
  infrared triplet), as well as FeH lines, from which the magnetic field
  can be inferred. Correlating the time series of these features with
  each other, and with wavelength-dependent radial velocities, provides
  excellent handles for the discrimination between planetary companions
  and stellar radial velocity jitter. These data are also generating
  new insight into the physical properties of M dwarf atmospheres, and
  the impact of activity and flares on the habitability of M star planets.

Title: Kepler Object of Interest Network. I. First results combining
    ground- and space-based observations of Kepler systems with transit
    timing variations
Authors: von Essen, C.; Ofir, A.; Dreizler, S.; Agol, E.; Freudenthal,
   J.; Hernández, J.; Wedemeyer, S.; Parkash, V.; Deeg, H. J.; Hoyer, S.;
   Morris, B. M.; Becker, A. C.; Sun, L.; Gu, S. H.; Herrero, E.; Tal-Or,
   L.; Poppenhaeger, K.; Mallonn, M.; Albrecht, S.; Khalafinejad, S.;
   Boumis, P.; Delgado-Correal, C.; Fabrycky, D. C.; Janulis, R.; Lalitha,
   S.; Liakos, A.; Mikolaitis, Š.; Moyano D'Angelo, M. L.; Sokov, E.;
   Pakštienė, E.; Popov, A.; Krushinsky, V.; Ribas, I.; Rodríguez S.,
   M. M.; Rusov, S.; Sokova, I.; Tautvaišienė, G.; Wang, X.
Bibcode: 2018A&A...615A..79V
Altcode: 2018arXiv180106191V
  During its four years of photometric observations, the Kepler
  space telescope detected thousands of exoplanets and exoplanet
  candidates. One of Kepler's greatest heritages has been the confirmation
  and characterization of hundreds of multi-planet systems via transit
  timing variations (TTVs). However, there are many interesting candidate
  systems displaying TTVs on such long timescales that the existing Kepler
  observations are of insufficient length to confirm and characterize
  them by means of this technique. To continue with Kepler's unique work,
  we have organized the "Kepler Object of Interest Network" (KOINet),
  a multi-site network formed of several telescopes located throughout
  America, Europe, and Asia. The goals of KOINet are to complete the TTV
  curves of systems where Kepler did not cover the interaction timescales
  well, to dynamically prove that some candidates are true planets (or
  not), to dynamically measure the masses and bulk densities of some
  planets, to find evidence for non-transiting planets in some of the
  systems, to extend Kepler's baseline adding new data with the main
  purpose of improving current models of TTVs, and to build a platform
  that can observe almost anywhere on the northern hemisphere, at almost
  any time. KOINet has been operational since March 2014. Here we show
  some promising first results obtained from analyzing seven primary
  transits of KOI-0410.01, KOI-0525.01, KOI-0760.01, and KOI-0902.01,
  in addition to the Kepler data acquired during the first and second
  observing seasons of KOINet. While carefully choosing the targets
  we set demanding constraints on timing precision (at least 1 min)
  and photometric precision (as good as one part per thousand) that
  were achieved by means of our observing strategies and data analysis
  techniques. For KOI-0410.01, new transit data revealed a turnover
  of its TTVs. We carried out an in-depth study of the system, which is
  identified in the NASA Data Validation Report as a false positive. Among
  others, we investigated a gravitationally bound hierarchical triple
  star system and a planet-star system. While the simultaneous transit
  fitting of ground- andspace-based data allowed for a planet solution,
  we could not fully reject the three-star scenario. New data,
  already scheduled in the upcoming 2018 observing season, will set
  tighter constraints on the nature of the system. <P />Ground-based
  photometry is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/615/A79">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/615/A79</A>

Title: VizieR Online Data Catalog: 324 CARMENES M dwarfs velocities
    (Reiners+, 2018)
Authors: Reiners, A.; Zechmeister, M.; Caballero, J. A.; Ribas, I.;
   Morales, J. C.; Jeffers, S. V.; Schofer, P.; Tal-Or, L.; Quirrenbach,
   A.; Amado, P. J.; Kaminski, A.; Seifert, W.; Abril, M.; Aceituno,
   J.; Alonso-Floriano, F. J.; Ammler-von Eiff, M.; Antona, R.;
   Anglada-Escude, G.; Anwand-Heerwart, H.; Arroyo-Torres, B.; Azzaro,
   M.; Baroch, D.; Barrado, D.; Bauer, F. F.; Becerril, S.; Bejar,
   V. J. S.; Benitez, D.; Berdinas, Z. M.; Bergond, G.; Blumcke, M.;
   Brinkmoller, M.; Del Burgo, C.; Cano, J.; Cardenas Vazquez, M. C.;
   Casal, E.; Cifuentes, C.; Claret, A.; Colome, J.; Cortes-Contreras,
   M.; Czesla, S.; Diez-Alonso, E.; Dreizler, S.; Feiz, C.; Fernandez, M.;
   Ferro, I. M.; Fuhrmeister, B.; Galadi-Enriquez, D.; Garcia-Piquer, A.;
   Garcia Vargas, M. L.; Gesa, L.; Gomez Galera, V.; Gonzalez Hernandez,
   J. I.; Gonzalez-Peinado, R.; Grozinger, U.; Grohnert, S.; Guardia,
   J.; Guenther, E. W.; Guijarro, A.; de Guindos, E.; Gutierrez-Soto,
   J.; Hagen, H. -J.; Hatzes, A. P.; Hauschildt, P. H.; Hedrosa,
   R. P.; Helmling, J.; Henning, T.; Hermelo, I.; Hernandez Arabi, R.;
   Hernandez Castano, L.; Hernandez Hernando, F.; Herrero, E.; Huber, A.;
   Huke, P.; Johnson, E. N.; de Juan, E.; Kim, M.; Klein, R.; Kluter,
   J.; Klutsch, A.; Kurster, M.; Lafarga, M.; Lamert, A.; Lampon, M.;
   Lara, L. M.; Laun, W.; Lemke, U.; Lenzen, R.; Launhardt, R.; Lopez
   Del Fresno, M.; Lopez-Gonzalez, J.; Lopez-Puertas, M.; Lopez Salas,
   J. F.; Lopez-Santiago, J.; Luque, R.; Magan Madinabeitia, H.; Mall,
   U.; Mancini, L.; Mandel, H.; Marfil, E.; Marin Molina, J. A.; Maroto
   Fernandez, D.; Martin, E. L.; Martin-Ruiz, S.; Marvin, C. J.; Mathar,
   R. J.; Mirabet, E.; Montes, D.; Moreno-Raya, M. E.; Moya, A.; Mundt,
   R.; Nagel, E.; Naranjo, V.; Nortmann, L.; Nowak, G.; Ofir, A.; Oreiro,
   R.; Palle, E.; Panduro, J.; Pascual, J.; Passegger, V. M.; Pavlov,
   A.; Pedraz, S.; Perez-Calpena, A.; Perez Medialdea, D.; Perger,
   M.; Perryman, M. A. C.; Pluto, M.; Rabaza, O.; Ramon, A.; Rebolo,
   R.; Redondo, P.; Reffert, S.; Reinhart, S.; Rhode, P.; Rix, H. -W.;
   Rodler, F.; Rodriguez, E.; Rodriguez-Lopez, C.; Rodriguez Trinidad,
   A.; Rohloff, R. -R.; Rosich, A.; Sadegi, S.; Sanchez-Blanco, E.;
   Sanchez Carrasco, M. A.; Sanchez-Lopez, A.; Sanz-Forcada, J.; Sarkis,
   P.; Sarmiento, L. F.; Schafer, S.; Schmitt, J. H. M. M.; Schiller, J.;
   Schweitzer, A.; Solano, E.; Stahl, O.; Strachan, J. B. P.; Sturmer,
   J.; Suarez, J. C.; Tabernero, H. M.; Tala, M.; Trifonov, T.; Tulloch,
   S. M.; Ulbrich, R. G.; Veredas, G.; Vico Linares, J. I.; Vilardell,
   F.; Wagner, K.; Winkler, J.; Wolthoff, V.; Xu, W.; Yan, F.; Zapatero
   Osorio, M. R.
Bibcode: 2018yCat..36120049R
Altcode:
  As part of the GTO agreement, we provide early access to one CARMENES
  spectrum for each of our sample targets (Table B.1). They can be
  downloaded from the CARMENES GTO Data Archive (Caballero et al., 2016,
  in Observatory Operations: Strategies, Processes, and Systems VI,
  Proc. SPIE, 9910, 99100E) (http://carmenes.cab.inta-csic.es) <P />(1
  data file).

Title: The CARMENES Search for Exoplanets around M Dwarfs: A Low-mass
    Planet in the Temperate Zone of the Nearby K2-18
Authors: Sarkis, Paula; Henning, Thomas; Kürster, Martin; Trifonov,
   Trifon; Zechmeister, Mathias; Tal-Or, Lev; Anglada-Escudé, Guillem;
   Hatzes, Artie P.; Lafarga, Marina; Dreizler, Stefan; Ribas, Ignasi;
   Caballero, José A.; Reiners, Ansgar; Mallonn, Matthias; Morales,
   Juan C.; Kaminski, Adrian; Aceituno, Jesús; Amado, Pedro J.; Béjar,
   Victor J. S.; Hagen, Hans-Jürgen; Jeffers, Sandra; Quirrenbach,
   Andreas; Launhardt, Ralf; Marvin, Christopher; Montes, David
Bibcode: 2018AJ....155..257S
Altcode: 2018arXiv180500830S; 2018arXiv180500830P
  K2-18 is a nearby M2.5 dwarf, located at 34 pc and hosting a transiting
  planet that was first discovered by the K2 mission and later confirmed
  with Spitzer Space Telescope observations. With a radius of ∼2 R
  <SUB>⊕</SUB> and an orbital period of ∼33 days, the planet lies in
  the temperate zone of its host star and receives stellar irradiation
  similar to that of Earth. Here we perform radial velocity follow-up
  observations with the visual channel of CARMENES with the goal of
  determining the mass and density of the planet. We measure a planetary
  semi-amplitude of K <SUB> b </SUB> ∼ 3.5 {{m}} {{{s}}}<SUP>-1</SUP>
  and a mass of M <SUB> b </SUB> ∼ 9 M <SUB>⊕</SUB>, yielding a bulk
  density around {ρ }<SUB>b</SUB>∼ 4 {{g}} {cm}}<SUP>-3</SUP>. This
  indicates a low-mass planet with a composition consistent with a solid
  core and a volatile-rich envelope. A signal at 9 days was recently
  reported using radial velocity measurements taken with the HARPS
  spectrograph. This was interpreted as being due to a second planet. We
  see a weaker, time- and wavelength-dependent signal in the CARMENES
  data set and thus favor stellar activity for its origin. K2-18 b joins
  the growing group of low-mass planets detected in the temperate zone
  of M dwarfs. The brightness of the host star in the near-infrared
  makes the system a good target for detailed atmospheric studies with
  the James Webb Space Telescope.

Title: The CARMENES search for exoplanets around M
    dwarfs. Radial-velocity variations of active stars in visual-channel
    spectra
Authors: Tal-Or, L.; Zechmeister, M.; Reiners, A.; Jeffers, S. V.;
   Schöfer, P.; Quirrenbach, A.; Amado, P. J.; Ribas, I.; Caballero,
   J. A.; Aceituno, J.; Bauer, F. F.; Béjar, V. J. S.; Czesla,
   S.; Dreizler, S.; Fuhrmeister, B.; Hatzes, A. P.; Johnson, E. N.;
   Kürster, M.; Lafarga, M.; Montes, D.; Morales, J. C.; Reffert, S.;
   Sadegi, S.; Seifert, W.; Shulyak, D.
Bibcode: 2018A&A...614A.122T
Altcode: 2018arXiv180302338T
  Context. Previous simulations predicted the activity-induced
  radial-velocity (RV) variations of M dwarfs to range from 1 cm
  s<SUP>-1</SUP> to 1 km s<SUP>-1</SUP>, depending on various stellar
  and activity parameters. <BR /> Aims: We investigate the observed
  relations between RVs, stellar activity, and stellar parameters of M
  dwarfs by analyzing CARMENES high-resolution visual-channel spectra
  (0.5-1μm), which were taken within the CARMENES RV planet survey
  during its first 20 months of operation. <BR /> Methods: During this
  time, 287 of the CARMENES-sample stars were observed at least five
  times. From each spectrum we derived a relative RV and a measure of
  chromospheric Hα emission. In addition, we estimated the chromatic
  index (CRX) of each spectrum, which is a measure of the RV wavelength
  dependence. <BR /> Results: Despite having a median number of only
  11 measurements per star, we show that the RV variations of the
  stars with RV scatter of &gt;10 m s<SUP>-1</SUP> and a projected
  rotation velocity v sin i &gt; 2 km s<SUP>-1</SUP> are caused mainly
  by activity. We name these stars "active RV-loud stars" and find their
  occurrence to increase with spectral type: from 3% for early-type M
  dwarfs (M0.0-2.5 V) through 30% for mid-type M dwarfs (M3.0-5.5 V)
  to &gt;50% for late-type M dwarfs (M6.0-9.0 V). Their RV-scatter
  amplitude is found to be correlated mainly with v sin i. For about
  half of the stars, we also find a linear RV-CRX anticorrelation, which
  indicates that their activity-induced RV scatter is lower at longer
  wavelengths. For most of them we can exclude a linear correlation
  between RV and Hα emission. <BR /> Conclusions: Our results are
  in agreement with simulated activity-induced RV variations in M
  dwarfs. The RV variations of most active RV-loud M dwarfs are likely
  to be caused by dark spots on their surfaces, which move in and out of
  view as the stars rotate. <P />The data presented in Figs. 5 and A.1
  are only available in electronic form at the CDS via anonymous ftp to
  <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://130.79.128.5">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/614/A122">http://cdsarc.u-strasbg.fr/viz-
  bin/qcat?J/A+A/614/A122</A>

Title: The CARMENES search for exoplanets around M
    dwarfs. High-resolution optical and near-infrared spectroscopy of
    324 survey stars
Authors: Reiners, A.; Zechmeister, M.; Caballero, J. A.; Ribas,
   I.; Morales, J. C.; Jeffers, S. V.; Schöfer, P.; Tal-Or, L.;
   Quirrenbach, A.; Amado, P. J.; Kaminski, A.; Seifert, W.; Abril, M.;
   Aceituno, J.; Alonso-Floriano, F. J.; Ammler-von Eiff, M.; Antona,
   R.; Anglada-Escudé, G.; Anwand-Heerwart, H.; Arroyo-Torres, B.;
   Azzaro, M.; Baroch, D.; Barrado, D.; Bauer, F. F.; Becerril,
   S.; Béjar, V. J. S.; Benítez, D.; Berdinas, Z. M.; Bergond,
   G.; Blümcke, M.; Brinkmöller, M.; del Burgo, C.; Cano, J.;
   Cárdenas Vázquez, M. C.; Casal, E.; Cifuentes, C.; Claret, A.;
   Colomé, J.; Cortés-Contreras, M.; Czesla, S.; Díez-Alonso, E.;
   Dreizler, S.; Feiz, C.; Fernández, M.; Ferro, I. M.; Fuhrmeister, B.;
   Galadí-Enríquez, D.; Garcia-Piquer, A.; García Vargas, M. L.; Gesa,
   L.; Gómez Galera, V.; González Hernández, J. I.; González-Peinado,
   R.; Grözinger, U.; Grohnert, S.; Guàrdia, J.; Guenther, E. W.;
   Guijarro, A.; de Guindos, E.; Gutiérrez-Soto, J.; Hagen, H. -J.;
   Hatzes, A. P.; Hauschildt, P. H.; Hedrosa, R. P.; Helmling, J.;
   Henning, Th.; Hermelo, I.; Hernández Arabí, R.; Hernández Castaño,
   L.; Hernández Hernando, F.; Herrero, E.; Huber, A.; Huke, P.; Johnson,
   E. N.; de Juan, E.; Kim, M.; Klein, R.; Klüter, J.; Klutsch, A.;
   Kürster, M.; Lafarga, M.; Lamert, A.; Lampón, M.; Lara, L. M.;
   Laun, W.; Lemke, U.; Lenzen, R.; Launhardt, R.; López del Fresno,
   M.; López-González, J.; López-Puertas, M.; López Salas, J. F.;
   López-Santiago, J.; Luque, R.; Magán Madinabeitia, H.; Mall, U.;
   Mancini, L.; Mandel, H.; Marfil, E.; Marín Molina, J. A.; Maroto
   Fernández, D.; Martín, E. L.; Martín-Ruiz, S.; Marvin, C. J.;
   Mathar, R. J.; Mirabet, E.; Montes, D.; Moreno-Raya, M. E.; Moya, A.;
   Mundt, R.; Nagel, E.; Naranjo, V.; Nortmann, L.; Nowak, G.; Ofir,
   A.; Oreiro, R.; Pallé, E.; Panduro, J.; Pascual, J.; Passegger,
   V. M.; Pavlov, A.; Pedraz, S.; Pérez-Calpena, A.; Pérez Medialdea,
   D.; Perger, M.; Perryman, M. A. C.; Pluto, M.; Rabaza, O.; Ramón,
   A.; Rebolo, R.; Redondo, P.; Reffert, S.; Reinhart, S.; Rhode, P.;
   Rix, H. -W.; Rodler, F.; Rodríguez, E.; Rodríguez-López, C.;
   Rodríguez Trinidad, A.; Rohloff, R. -R.; Rosich, A.; Sadegi, S.;
   Sánchez-Blanco, E.; Sánchez Carrasco, M. A.; Sánchez-López, A.;
   Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schäfer, S.; Schmitt,
   J. H. M. M.; Schiller, J.; Schweitzer, A.; Solano, E.; Stahl, O.;
   Strachan, J. B. P.; Stürmer, J.; Suárez, J. C.; Tabernero, H. M.;
   Tala, M.; Trifonov, T.; Tulloch, S. M.; Ulbrich, R. G.; Veredas, G.;
   Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Winkler, J.; Wolthoff,
   V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2018A&A...612A..49R
Altcode: 2017arXiv171106576R
  The CARMENES radial velocity (RV) survey is observing 324 M dwarfs to
  search for any orbiting planets. In this paper, we present the survey
  sample by publishing one CARMENES spectrum for each M dwarf. These
  spectra cover the wavelength range 520-1710 nm at a resolution of
  at least R &gt;80 000, and we measure its RV, Hα emission, and
  projected rotation velocity. We present an atlas of high-resolution
  M-dwarf spectra and compare the spectra to atmospheric models. To
  quantify the RV precision that can be achieved in low-mass stars over
  the CARMENES wavelength range, we analyze our empirical information
  on the RV precision from more than 6500 observations. We compare our
  high-resolution M-dwarf spectra to atmospheric models where we determine
  the spectroscopic RV information content, Q, and signal-to-noise
  ratio. We find that for all M-type dwarfs, the highest RV precision can
  be reached in the wavelength range 700-900 nm. Observations at longer
  wavelengths are equally precise only at the very latest spectral types
  (M8 and M9). We demonstrate that in this spectroscopic range, the large
  amount of absorption features compensates for the intrinsic faintness
  of an M7 star. To reach an RV precision of 1 m s<SUP>-1</SUP> in very
  low mass M dwarfs at longer wavelengths likely requires the use of a 10
  m class telescope. For spectral types M6 and earlier, the combination
  of a red visual and a near-infrared spectrograph is ideal to search
  for low-mass planets and to distinguish between planets and stellar
  variability. At a 4 m class telescope, an instrument like CARMENES has
  the potential to push the RV precision well below the typical jitter
  level of 3-4 m s<SUP>-1</SUP>.

Title: Lyman-continuum leakage as dominant source of diffuse ionized
    gas in the Antennae galaxy
Authors: Weilbacher, Peter M.; Monreal-Ibero, Ana; Verhamme,
   Anne; Sandin, Christer; Steinmetz, Matthias; Kollatschny, Wolfram;
   Krajnović, Davor; Kamann, Sebastian; Roth, Martin M.; Erroz-Ferrer,
   Santiago; Marino, Raffaella Anna; Maseda, Michael V.; Wendt, Martin;
   Bacon, Roland; Dreizler, Stefan; Richard, Johan; Wisotzki, Lutz
Bibcode: 2018A&A...611A..95W
Altcode: 2017arXiv171204450W
  The Antennae galaxy (NGC 4038/39) is the closest major interacting
  galaxy system and is therefore often studied as a merger prototype. We
  present the first comprehensive integral field spectroscopic dataset of
  this system, observed with the MUSE instrument at the ESO VLT. We cover
  the two regions in this system which exhibit recent star formation:
  the central galaxy interaction and a region near the tip of the
  southern tidal tail. In these fields, we detect HII regions and diffuse
  ionized gas to unprecedented depth. About 15% of the ionized gas was
  undetected by previous observing campaigns. This newly detected faint
  ionized gas is visible everywhere around the central merger, and shows
  filamentary structure. We estimate diffuse gas fractions of about
  60% in the central field and 10% in the southern region. We are able
  to show that the southern region contains a significantly different
  population of HII regions, showing fainter luminosities. By comparing
  HII region luminosities with the HST catalog of young star clusters
  in the central field, we estimate that there is enough Lyman-continuum
  leakage in the merger to explain the amount of diffuse ionized gas that
  we detect. We compare the Lyman-continuum escape fraction of each HII
  region against emission line ratios that are sensitive to the ionization
  parameter. While we find no systematic trend between these properties,
  the most extreme line ratios seem to be strong indicators of density
  bounded ionization. Extrapolating the Lyman-continuum escape fractions
  to the southern region, we conclude that simply from the comparison
  of the young stellar populations to the ionized gas there is no need
  to invoke other ionization mechanisms than Lyman-continuum leaking HII
  regions for the diffuse ionized gas in the Antennae. <P />FITS images
  and Table of HII regions are available at the CDS via anonymous ftp
  to <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://cdsarc.u-strasbg.fr">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A95">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A95</A>
  and at <A
  href="https://muse-vlt.eu/science/antennae/">http://muse-vlt.eu/science/antennae/</A>

Title: VizieR Online Data Catalog: Radial-velocity of CARMENES M
    dwarfs (Tal-Or+, 2018)
Authors: Tal-Or, L.; Zechmeister, M.; Reiners, A.; Jeffers, S. V.;
   Schoefer, P.; Quirrenbach, A.; Amado, P. J.; Ribas, I.; Caballero,
   J. A.; Aceituno, J.; Bauer, F. F.; Bejar, V. J. S.; Czesla, S.;
   Dreizler, S.; Fuhrmeister, B.; Hatzes, A. P.; Johnson, E. N.; Kurster,
   M.; Lafarga, M.; Montes, D.; Morales, J. C.; Reffert, S.; Sadegi,
   S.; Seifert, W.; Shulyak, D.
Bibcode: 2018yCat..36140122T
Altcode:
  The catalogue contains the data presented in Figures 5 and A.1 of the
  source paper. <P />(2 data files).

Title: The Radial Velocity Variability of the K-giant γ Draconis:
    Stellar Variability Masquerading as a Planet
Authors: Hatzes, A. P.; Endl, M.; Cochran, W. D.; MacQueen, P. J.;
   Han, I.; Lee, B. -C.; Kim, K. -M.; Mkrtichian, D.; Döllinger, M.;
   Hartmann, M.; Karjalainen, M.; Dreizler, S.
Bibcode: 2018AJ....155..120H
Altcode: 2018arXiv180105239H
  We present precise stellar radial velocity (RV) measurements of γ Dra
  taken from 2003 to 2017. The data from 2003 to 2011 show coherent,
  long-lived variations with a period of 702 days. These variations
  are consistent with the presence of a planetary companion having m
  sin i = 10.7 M <SUB>Jup</SUB> whose orbital properties are typical
  for giant planets found around evolved stars. An analysis of the
  Hipparcos photometry, Ca II S-index measurements, and measurements
  of the spectral line shapes during this time show no variations with
  the RV of the planet, which seems to “confirm” the presence of
  the planet. However, RV measurements taken from 2011-2017 seem to
  refute this. From 2011-2013, the RV variations virtually disappear,
  only to return in 2014 but with a noticeable phase shift. The total RV
  variations are consistent either with amplitude variations on timescales
  of ≈10.6 year, or the beating effect between two periods of 666
  and 801 days. It seems unlikely that both these signals stem from a
  two-planet system. A simple dynamical analysis indicates that there
  is only a 1%-2% chance that the two-planet system is stable. Rather,
  we suggest that this multi-periodic behavior may represent a new form
  of stellar variability, possibly related to oscillatory convective
  modes. If such intrinsic stellar variability is common around K
  giant stars and is attributed to planetary companions, then the
  planet occurrence rate among these stars may be significantly lower
  than thought.

Title: A detached stellar-mass black hole candidate in the globular
    cluster NGC 3201
Authors: Giesers, Benjamin; Dreizler, Stefan; Husser, Tim-Oliver;
   Kamann, Sebastian; Anglada Escudé, Guillem; Brinchmann, Jarle;
   Carollo, C. Marcella; Roth, Martin M.; Weilbacher, Peter M.; Wisotzki,
   Lutz
Bibcode: 2018MNRAS.475L..15G
Altcode: 2018arXiv180105642G
  As part of our massive spectroscopic survey of 25 Galactic globular
  clusters with MUSE, we performed multiple epoch observations of NGC
  3201 with the aim of constraining the binary fraction. In this cluster,
  we found one curious star at the main-sequence turn-off with radial
  velocity variations of the order of 100 km s<SUP>- 1</SUP>, indicating
  the membership to a binary system with an unseen component since no
  other variations appear in the spectra. Using an adapted variant of the
  generalized Lomb-Scargle periodogram, we could calculate the orbital
  parameters and found the companion to be a detached stellar-mass
  black hole with a minimum mass of 4.36 ± 0.41 M<SUB>⊙</SUB>. The
  result is an important constraint for binary and black hole evolution
  models in globular clusters as well as in the context of gravitational
  wave sources.

Title: VizieR Online Data Catalog: Temporal evolution of
    neutron-capture elements (Spina+, 2018)
Authors: Spina, L.; Melendez, J.; Karakas, A. I.; Dos Santos, L.;
   Bedell, M.; Asplund, M.; Ramirez, I.; Yong, D.; Alves-Brito, A.;
   Bean, J. L.; Dreizler, S.
Bibcode: 2018yCat..74742580S
Altcode:
  Spectroscopic parameters and abundances for the 79 solar twin stars
  analysed in this paper. <P />(4 data files).

Title: The CARMENES search for exoplanets around M dwarfs . First
    visual-channel radial-velocity measurements and orbital parameter
    updates of seven M-dwarf planetary systems
Authors: Trifonov, T.; Kürster, M.; Zechmeister, M.; Tal-Or,
   L.; Caballero, J. A.; Quirrenbach, A.; Amado, P. J.; Ribas, I.;
   Reiners, A.; Reffert, S.; Dreizler, S.; Hatzes, A. P.; Kaminski, A.;
   Launhardt, R.; Henning, Th.; Montes, D.; Béjar, V. J. S.; Mundt,
   R.; Pavlov, A.; Schmitt, J. H. M. M.; Seifert, W.; Morales, J. C.;
   Nowak, G.; Jeffers, S. V.; Rodríguez-López, C.; del Burgo, C.;
   Anglada-Escudé, G.; López-Santiago, J.; Mathar, R. J.; Ammler-von
   Eiff, M.; Guenther, E. W.; Barrado, D.; González Hernández, J. I.;
   Mancini, L.; Stürmer, J.; Abril, M.; Aceituno, J.; Alonso-Floriano,
   F. J.; Antona, R.; Anwand-Heerwart, H.; Arroyo-Torres, B.; Azzaro,
   M.; Baroch, D.; Bauer, F. F.; Becerril, S.; Benítez, D.; Berdiñas,
   Z. M.; Bergond, G.; Blümcke, M.; Brinkmöller, M.; Cano, J.; Cárdenas
   Vázquez, M. C.; Casal, E.; Cifuentes, C.; Claret, A.; Colomé,
   J.; Cortés-Contreras, M.; Czesla, S.; Díez-Alonso, E.; Feiz, C.;
   Fernández, M.; Ferro, I. M.; Fuhrmeister, B.; Galadí-Enríquez, D.;
   Garcia-Piquer, A.; García Vargas, M. L.; Gesa, L.; Gómez Galera,
   V.; González-Peinado, R.; Grözinger, U.; Grohnert, S.; Guàrdia,
   J.; Guijarro, A.; de Guindos, E.; Gutiérrez-Soto, J.; Hagen,
   H. -J.; Hauschildt, P. H.; Hedrosa, R. P.; Helmling, J.; Hermelo, I.;
   Hernández Arabí, R.; Hernández Castaño, L.; Hernández Hernando,
   F.; Herrero, E.; Huber, A.; Huke, P.; Johnson, E.; de Juan, E.; Kim,
   M.; Klein, R.; Klüter, J.; Klutsch, A.; Lafarga, M.; Lampón, M.;
   Lara, L. M.; Laun, W.; Lemke, U.; Lenzen, R.; López del Fresno, M.;
   López-González, M. J.; López-Puertas, M.; López Salas, J. F.;
   Luque, R.; Magán Madinabeitia, H.; Mall, U.; Mandel, H.; Marfil,
   E.; Marín Molina, J. A.; Maroto Fernández, D.; Martín, E. L.;
   Martín-Ruiz, S.; Marvin, C. J.; Mirabet, E.; Moya, A.; Moreno-Raya,
   M. E.; Nagel, E.; Naranjo, V.; Nortmann, L.; Ofir, A.; Oreiro, R.;
   Pallé, E.; Panduro, J.; Pascual, J.; Passegger, V. M.; Pedraz,
   S.; Pérez-Calpena, A.; Pérez Medialdea, D.; Perger, M.; Perryman,
   M. A. C.; Pluto, M.; Rabaza, O.; Ramón, A.; Rebolo, R.; Redondo,
   P.; Reinhardt, S.; Rhode, P.; Rix, H. -W.; Rodler, F.; Rodríguez,
   E.; Rodríguez Trinidad, A.; Rohloff, R. -R.; Rosich, A.; Sadegi, S.;
   Sánchez-Blanco, E.; Sánchez Carrasco, M. A.; Sánchez-López, A.;
   Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schäfer, S.; Schiller,
   J.; Schöfer, P.; Schweitzer, A.; Solano, E.; Stahl, O.; Strachan,
   J. B. P.; Suárez, J. C.; Tabernero, H. M.; Tala, M.; Tulloch, S. M.;
   Veredas, G.; Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Winkler,
   J.; Wolthoff, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2018A&A...609A.117T
Altcode: 2017arXiv171001595T
  Context. The main goal of the CARMENES survey is to find Earth-mass
  planets around nearby M-dwarf stars. Seven M dwarfs included in the
  CARMENES sample had been observed before with HIRES and HARPS and
  either were reported to have one short period planetary companion (GJ
  15 A, GJ 176, GJ 436, GJ 536 and GJ 1148) or are multiple planetary
  systems (GJ 581 and GJ 876). <BR /> Aims: We aim to report new precise
  optical radial velocity measurements for these planet hosts and test
  the overall capabilities of CARMENES. <BR /> Methods: We combined our
  CARMENES precise Doppler measurements with those available from HIRES
  and HARPS and derived new orbital parameters for the systems. Bona-fide
  single planet systems were fitted with a Keplerian model. The multiple
  planet systems were analyzed using a self-consistent dynamical model
  and their best fit orbits were tested for long-term stability. <BR />
  Results: We confirm or provide supportive arguments for planets around
  all the investigated stars except for GJ 15 A, for which we find that
  the post-discovery HIRES data and our CARMENES data do not show a
  signal at 11.4 days. Although we cannot confirm the super-Earth planet
  GJ 15 Ab, we show evidence for a possible long-period (P<SUB>c</SUB> =
  7030<SUB>-630</SUB><SUP>+970</SUP> d) Saturn-mass (m<SUB>c</SUB>sini
  = 51.8M<SUB>⊕</SUB>) planet around GJ 15 A. In addition, based
  on our CARMENES and HIRES data we discover a second planet around
  GJ 1148, for which we estimate a period P<SUB>c</SUB> = 532.6 days,
  eccentricity e<SUB>c</SUB> = 0.342 and minimum mass m<SUB>c</SUB>sini =
  68.1M<SUB>⊕</SUB>. <BR /> Conclusions: The CARMENES optical radial
  velocities have similar precision and overall scatter when compared
  to the Doppler measurements conducted with HARPS and HIRES. We
  conclude that CARMENES is an instrument that is up to the challenge
  of discovering rocky planets around low-mass stars. <P />Based on
  observations collected at the European Organisation for Astronomical
  Research in the Southern Hemisphere under ESO programmes 072.C-0488,
  072.C-0513, 074.C-0012, 074.C-0364, 075.D-0614, 076.C-0878, 077.C-0364,
  077.C-0530, 078.C-0044, 078.C-0833, 079.C-0681, 183.C-0437, 60.A-9036,
  082.C-0718, 183.C-0972, 085.C-0019, 087.C-0831, 191.C-0873. The
  appendix tables are only available at the CDS via anonymous ftp to
  <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://130.79.128.5">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/609/A117">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/609/A117</A>

Title: A stellar census in globular clusters with MUSE: The
    contribution of rotation to cluster dynamics studied with 200
    000 stars
Authors: Kamann, S.; Husser, T. -O.; Dreizler, S.; Emsellem, E.;
   Weilbacher, P. M.; Martens, S.; Bacon, R.; den Brok, M.; Giesers,
   B.; Krajnović, D.; Roth, M. M.; Wendt, M.; Wisotzki, L.
Bibcode: 2018MNRAS.473.5591K
Altcode: 2017arXiv171007257K
  This is the first of a series of papers presenting the results from our
  survey of 25 Galactic globular clusters with the MUSE integral-field
  spectrograph. In combination with our dedicated algorithm for source
  deblending, MUSE provides unique multiplex capabilities in crowded
  stellar fields and allows us to acquire samples of up to 20 000 stars
  within the half-light radius of each cluster. The present paper focuses
  on the analysis of the internal dynamics of 22 out of the 25 clusters,
  using about 500 000 spectra of 200 000 individual stars. Thanks to the
  large stellar samples per cluster, we are able to perform a detailed
  analysis of the central rotation and dispersion fields using both
  radial profiles and two-dimensional maps. The velocity dispersion
  profiles we derive show a good general agreement with existing radial
  velocity studies but typically reach closer to the cluster centres. By
  comparison with proper motion data, we derive or update the dynamical
  distance estimates to 14 clusters. Compared to previous dynamical
  distance estimates for 47 Tuc, our value is in much better agreement
  with other methods. We further find significant (&gt;3σ) rotation in
  the majority (13/22) of our clusters. Our analysis seems to confirm
  earlier findings of a link between rotation and the ellipticities
  of globular clusters. In addition, we find a correlation between the
  strengths of internal rotation and the relaxation times of the clusters,
  suggesting that the central rotation fields are relics of the cluster
  formation that are gradually dissipated via two-body relaxation.

Title: The temporal evolution of neutron-capture elements in the
    Galactic discs
Authors: Spina, Lorenzo; Meléndez, Jorge; Karakas, Amanda I.; dos
   Santos, Leonardo; Bedell, Megan; Asplund, Martin; Ramírez, Ivan;
   Yong, David; Alves-Brito, Alan; Bean, Jacob L.; Dreizler, Stefan
Bibcode: 2018MNRAS.474.2580S
Altcode: 2017arXiv171103643S
  Important insights into the formation and evolution of the Galactic
  disc(s) are contained in the chemical compositions of stars. We
  analysed high-resolution and high signal-to-noise HARPS spectra of 79
  solar twin stars in order to obtain precise determinations of their
  atmospheric parameters, ages (σ ∼0.4 Gyr) and chemical abundances
  (σ &lt;0.01 dex) of 12 neutron-capture elements (Sr, Y, Zr, Ba, La,
  Ce, Pr, Nd, Sm, Eu, Gd and Dy). This valuable data set allows us to
  study the [X/Fe]-age relations over a time interval of ∼10 Gyr and
  among stars belonging to the thin and thick discs. These relations show
  that (i) the s-process has been the main channel of nucleosynthesis
  of n-capture elements during the evolution of the thin disc; (ii)
  the thick disc is rich in r-process elements which suggests that its
  formation has been rapid and intensive. In addition, the heavy (Ba,
  La, Ce) and light (Sr, Y, Zr) s-process elements revealed details on
  the dependence between the yields of AGB stars and the stellar mass
  or metallicity. Finally, we confirmed that both [Y/Mg] and [Y/Al]
  ratios can be employed as stellar clocks, allowing ages of solar twin
  stars to be estimated with an average precision of ∼0.5 Gyr.

Title: The CARMENES search for exoplanets around M dwarfs. HD147379 b:
    A nearby Neptune in the temperate zone of an early-M dwarf
Authors: Reiners, A.; Ribas, I.; Zechmeister, M.; Caballero, J. A.;
   Trifonov, T.; Dreizler, S.; Morales, J. C.; Tal-Or, L.; Lafarga,
   M.; Quirrenbach, A.; Amado, P. J.; Kaminski, A.; Jeffers, S. V.;
   Aceituno, J.; Béjar, V. J. S.; Guàrdia, J.; Guenther, E. W.; Hagen,
   H. -J.; Montes, D.; Passegger, V. M.; Seifert, W.; Schweitzer, A.;
   Cortés-Contreras, M.; Abril, M.; Alonso-Floriano, F. J.; Ammler-von
   Eiff, M.; Antona, R.; Anglada-Escudé, G.; Anwand-Heerwart, H.;
   Arroyo-Torres, B.; Azzaro, M.; Baroch, D.; Barrado, D.; Bauer,
   F. F.; Becerril, S.; Benítez, D.; Berdiñas, Z. M.; Bergond, G.;
   Blümcke, M.; Brinkmöller, M.; del Burgo, C.; Cano, J.; Cárdenas
   Vázquez, M. C.; Casal, E.; Cifuentes, C.; Claret, A.; Colomé, J.;
   Czesla, S.; Díez-Alonso, E.; Feiz, C.; Fernández, M.; Ferro, I. M.;
   Fuhrmeister, B.; Galadí-Enríquez, D.; Garcia-Piquer, A.; García
   Vargas, M. L.; Gesa, L.; Gómez Galera, V.; González Hernández,
   J. I.; González-Peinado, R.; Grözinger, U.; Grohnert, S.; Guijarro,
   A.; de Guindos, E.; Gutiérrez-Soto, J.; Hatzes, A. P.; Hauschildt,
   P. H.; Hedrosa, R. P.; Helmling, J.; Henning, Th.; Hermelo, I.;
   Hernández Arabí, R.; Hernández Castaño, L.; Hernández Hernando,
   F.; Herrero, E.; Huber, A.; Huke, P.; Johnson, E. N.; de Juan, E.; Kim,
   M.; Klein, R.; Klüter, J.; Klutsch, A.; Kürster, M.; Labarga, F.;
   Lamert, A.; Lampón, M.; Lara, L. M.; Laun, W.; Lemke, U.; Lenzen,
   R.; Launhardt, R.; López del Fresno, M.; López-González, M. J.;
   López-Puertas, M.; López Salas, J. F.; López-Santiago, J.; Luque,
   R.; Magán Madinabeitia, H.; Mall, U.; Mancini, L.; Mandel, H.;
   Marfil, E.; Marín Molina, J. A.; Maroto Fernández, D.; Martín,
   E. L.; Martín-Ruiz, S.; Marvin, C. J.; Mathar, R. J.; Mirabet, E.;
   Moreno-Raya, M. E.; Moya, A.; Mundt, R.; Nagel, E.; Naranjo, V.;
   Nortmann, L.; Nowak, G.; Ofir, A.; Oreiro, R.; Pallé, E.; Panduro,
   J.; Pascual, J.; Pavlov, A.; Pedraz, S.; Pérez-Calpena, A.; Pérez
   Medialdea, D.; Perger, M.; Perryman, M. A. C.; Pluto, M.; Rabaza,
   O.; Ramón, A.; Rebolo, R.; Redondo, P.; Reffert, S.; Reinhart, S.;
   Rhode, P.; Rix, H. -W.; Rodler, F.; Rodríguez, E.; Rodríguez-López,
   C.; Rodríguez Trinidad, A.; Rohloff, R. -R.; Rosich, A.; Sadegi,
   S.; Sánchez-Blanco, E.; Sánchez Carrasco, M. A.; Sánchez-López,
   A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schäfer, S.;
   Schmitt, J. H. M. M.; Schiller, J.; Schöfer, P.; Solano, E.; Stahl,
   O.; Strachan, J. B. P.; Stürmer, J.; Suárez, J. C.; Tabernero, H. M.;
   Tala, M.; Tulloch, S. M.; Ulbrich, R. -G.; Veredas, G.; Vico Linares,
   J. I.; Vilardell, F.; Wagner, K.; Winkler, J.; Wolthoff, V.; Xu, W.;
   Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2018A&A...609L...5R
Altcode: 2017arXiv171205797R
  We report on the first star discovered to host a planet detected by
  radial velocity (RV) observations obtained within the CARMENES survey
  for exoplanets around M dwarfs. HD 147379 (V = 8.9 mag, M = 0.58 ±
  0.08 M<SUB>⊙</SUB>), a bright M0.0 V star at a distance of 10.7 pc,
  is found to undergo periodic RV variations with a semi-amplitude of
  K = 5.1 ± 0.4 m s<SUP>-1</SUP> and a period of P = 86.54 ± 0.06
  d. The RV signal is found in our CARMENES data, which were taken
  between 2016 and 2017, and is supported by HIRES/Keck observations
  that were obtained since 2000. The RV variations are interpreted
  as resulting from a planet of minimum mass m<SUB>P</SUB> sin i =
  25 ± 2 M<SUB>⊕</SUB>, 1.5 times the mass of Neptune, with an
  orbital semi-major axis a = 0.32 au and low eccentricity (e &lt;
  0.13). HD 147379 b is orbiting inside the temperate zone around the
  star, where water could exist in liquid form. The RV time-series and
  various spectroscopic indicators show additional hints of variations
  at an approximate period of 21.1 d (and its first harmonic), which
  we attribute to the rotation period of the star. <P />RV data
  (Table A.1) are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/609/L5">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/609/L5</A>

Title: Spectroscopic binaries in the Solar Twin Planet Search program:
    from substellar-mass to M dwarf companions
Authors: dos Santos, Leonardo A.; Meléndez, Jorge; Bedell, Megan;
   Bean, Jacob L.; Spina, Lorenzo; Alves-Brito, Alan; Dreizler, Stefan;
   Ramírez, Iván; Asplund, Martin
Bibcode: 2017MNRAS.472.3425D
Altcode: 2017arXiv170807465D
  Previous studies on the rotation of Sun-like stars revealed that
  the rotational rates of young stars converge towards a well-defined
  evolution that follows a power-law decay. It seems, however, that some
  binary stars do not obey this relation, often by displaying enhanced
  rotational rates and activity. In the Solar Twin Planet Search program,
  we observed several solar twin binaries, and found a multiplicity
  fraction of 42 per cent ± 6 per cent in the whole sample; moreover,
  at least three of these binaries (HIP 19911, HIP 67620 and HIP 103983)
  clearly exhibit the aforementioned anomalies. We investigated the
  configuration of the binaries in the program, and discovered new
  companions for HIP 6407, HIP 54582, HIP 62039 and HIP 30037, of which
  the latter is orbited by a 0.06 M<SUB>⊙</SUB> brown dwarf in a 1
  m long orbit. We report the orbital parameters of the systems with
  well-sampled orbits and, in addition, the lower limits of parameters
  for the companions that only display a curvature in their radial
  velocities. For the linear trend binaries, we report an estimate
  of the masses of their companions when their observed separation
  is available, and a minimum mass otherwise. We conclude that solar
  twin binaries with low-mass stellar companions at moderate orbital
  periods do not display signs of a distinct rotational evolution when
  compared to single stars. We confirm that the three peculiar stars are
  double-lined binaries, and that their companions are polluting their
  spectra, which explains the observed anomalies.

Title: Mapping diffuse interstellar bands in the local ISM on small
    scales via MUSE 3D spectroscopy. A pilot study based on globular
    cluster NGC 6397
Authors: Wendt, Martin; Husser, Tim-Oliver; Kamann, Sebastian;
   Monreal-Ibero, Ana; Richter, Philipp; Brinchmann, Jarle; Dreizler,
   Stefan; Weilbacher, Peter M.; Wisotzki, Lutz
Bibcode: 2017A&A...607A.133W
Altcode: 2017arXiv170903982W
  Context. We map the interstellar medium (ISM) including the diffuse
  interstellar bands (DIBs) in absorption toward the globular cluster NGC
  6397 using VLT/MUSE. Assuming the absorbers are located at the rim of
  the Local Bubble we trace structures on the order of mpc (milliparsec,
  a few thousand AU). <BR /> Aims: We aimed to demonstrate the feasibility
  to map variations of DIBs on small scales with MUSE. The sightlines
  defined by binned stellar spectra are separated by only a few arcseconds
  and we probe the absorption within a physically connected region. <BR />
  Methods: This analysis utilized the fitting residuals of individual
  stellar spectra of NGC 6397 member stars and analyzed lines from
  neutral species and several DIBs in Voronoi-binned composite spectra
  with high signal-to-noise ratio (S/N). <BR /> Results: This pilot study
  demonstrates the power of MUSE for mapping the local ISM on very small
  scales which provides a new window for ISM observations. We detect small
  scale variations in Na I and K I as well as in several DIBs within
  few arcseconds, or mpc with regard to the Local Bubble. We verify
  the suitability of the MUSE 3D spectrograph for such measurements and
  gain new insights by probing a single physical absorber with multiple
  sight lines.

Title: VizieR Online Data Catalog: Diffuse ionized gas in the Antennae
    galaxy (Weilbacher+, 2018)
Authors: Weilbacher, P. M.; Monreal-Ibero, A.; Verhamme, A.; Sandin,
   C.; Steinmetz, M.; Kollatschny, W.; Krajnovic, D.; Kamann, S.; Roth,
   M. M.; Erroz-Ferrer, S.; Marino, R. A.; Maseda, M. V.; Wendt, M.;
   Bacon, R.; Dreizler, S.; Richard, J.; Wisotzki, L.
Bibcode: 2017yCat..36110095W
Altcode:
  We provide two-dimensional maps of two different ways to measure
  the diffuse ionized gas as traced by the Halpha emission line in the
  Antennae Galaxy, both for the central field and the field at the end
  of the southern tidal tail. We provide a velocity map derived from
  the Halpha emission line, binned to a S/N~30. Finally, we provide line
  measurements and derived properties for all HII regions discussed in
  the paper. <P />(4 data files).

Title: VizieR Online Data Catalog: HD147379 b velocity curve
    (Reiners+, 2018)
Authors: Reiners, A.; Ribas, I.; Zechmeister, M.; Caballero, J. A.;
   Trifonov, T.; Dreizler, S.; Morales, J. C.; Tal-Or, L.; Lafarga,
   M.; Quirrenbach, A.; Amado, P. J.; Kaminski, A.; Jeffers, S. V.;
   Aceituno, J.; Bejar, V. J. S.; Guardia, J.; Guenther, E. W.; Hagen,
   H. -J.; Montes, D.; Passegger, V. M.; Seifert, W.; Schweitzer, A.;
   Cortes-Contreras, M.; Abril, M.; Alonso-Floriano, F. J.; Ammler-von
   Eiff, M.; Antona, R.; Anglada-Escude, G.; Anwand-Heerwart, H.;
   Arroyo-Torres, B.; Azzaro, M.; Baroch, D.; Barrado, D.; Bauer, F. F.;
   Becerril, S.; Benitez, D.; Berdinas, Z. M.; Bergond, G.; Bluemcke,
   M.; Brinkmoeller, M.; Del Burgo, C.; Cano, J.; Cardenas Vazquez,
   M. C.; Casal, E.; Cifuentes, C.; Claret, A.; Colome, J.; Czesla, S.;
   Diez-Alonso, E.; Feiz, C.; Fernandez, M.; Ferro, I. M.; Fuhrmeister,
   B.; Galadi-Enriquez, D.; Garcia-Piquer, A.; Garcia Vargas, M. L.; Gesa,
   L.; Gomez Galera, V.; Gonzalez Hernandez, J. I.; Gonzalez-Peinado,
   R.; Groezinger, U.; Grohnert, S.; Guijarro, A.; de Guindos, E.;
   Gutierrez-Soto, J.; Hatzes, A. P.; Hauschildt, P. H.; Hedrosa,
   R. P.; Helml!, Ing J.; H Enning, Th.; Hermelo, I.; Hernandez Arabi,
   R.; Hernandez Castano, L.; Hernandez Hernando, F.; Herrero, E.;
   Huber, A.; Huke, P.; Johnson, E. N.; de Juan, E.; Kim, M.; Klein,
   R.; Klueter, J.; Klutsch, A.; Kuerster, M.; Labarga, F.; Lamert, A.;
   Lampon, M.; Lara, L. M.; Laun, W.; Lemke, U.; Lenzen, R.; Launhardt,
   R.; Lopez Del Fresno, M.; Lopez-Gonzalez, M. J.; Lopez-Puertas, M.;
   Lopez Salas, J. F.; Lopez-Santiago, J.; Luque, R.; Magan Madinabeitia,
   H.; Mall, U.; Mancini, L.; Mandel, H.; Marfil, E.; Marin Molina,
   J. A.; Maroto Fernandez, D.; Martin, E. L.; Martin-Ruiz, S.; Marvin,
   C. J.; Mathar, R. J.; Mirabet, E.; Moreno-Raya, M. E.; Moya, A.;
   Mundt, R.; Nagel, E.; Naranjo, V.; Nortmann, L.; Nowak, G.; Ofir, A.;
   Oreiro, R.; Palle, E.; Panduro, J.; Pascual, J.; Pavlov, A.; Pedraz,
   S.; Perez-Calpena, A.; Perez Medialdea, D.; Perger, M.; Perryman,
   M. A. C.; Pluto, M.; Rabaza, O.; Ramon, A.; Rebolo, R.; Redondo,
   P.; Reffert, S.; Reinhart, S.; Rhode, P.; Rix, H. -W.; Rodler, F.;
   Rodriguez, E.; Rodriguez-Lopez, C.; Rodriguez Trinidad, A.; Rohloff,
   R. -R.; Rosich, A.; ! Sadegi, S.; Sanchez-Blanco, E.; Sanchez Carrasco,
   M. A.; Sanchez-Lopez, A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento,
   L. F.; Schaefer, S.; Schmitt, J. H. M. M.; Schiller, J.; Schoefer,
   P.; Solano, E.; Stahl, O.; Strachan, J. B. P.; Stuermer, J.; Suarez,
   J. C.; Tabernero, H. M.; Tala, M.; Tulloch, S. M.; Ulbrich, R. -G.;
   Veredas, G.; Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Winkler,
   J.; Wolthoff, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2017yCat..36099005R
Altcode:
  We analyzed data from the CARMENES VIS channel and HIRES/Keck. The
  CARMENES measurements were taken in the context of the CARMENES search
  for exoplanets around M dwarfs. The CARMENES instrument consists of two
  channels: the VIS channel obtains spectra at a resolution of R=94600 in
  the wavelength range 520-960nm, while the NIR channel yields spectra of
  R=80400 covering 960-1710nm. Both channels are calibrated in wavelength
  with hollow-cathode lamps and use temperature- and pressure-stabilized
  Fabry-Perot etalons to interpolate the wavelength solution and
  simultaneously monitor the spectrograph drift during nightly operations
  (Bauer et al., 2015A&amp;A...581A.117B). <P />(1 data file).

Title: VizieR Online Data Catalog: CARMENES radial velocity curves
    of 7 M-dwarf (Trifonov+, 2018)
Authors: Trifonov, T.; Kuerster, M.; Zechmeister, M.; Tal-Or, L.;
   Caballero, J. A.; Quirrenbach, A.; Amado, P. J.; Ribas, I.; Reiners,
   A.; Reffert, S.; Dreizler, S.; Hatzes, A. P.; Kaminski, A.; Launhardt,
   R.; Henning, T.; Montes, D.; Bejar, V. J. S.; Mundt, R.; Pavlov,
   A.; Schmitt, J. H. M. M.; Seifert, W.; Morales, J. C.; Nowak, G.;
   Jeffers, S. V.; Rodriguez-Lopez, C.; Del Burgo, C.; Anglada-Escude,
   G.; Lopez-Santiago, J.; Mathar, R. J.; Ammler-von Eiff, M.; Guenther,
   E. W.; Barrado, D.; Gonzalez Hernandez, J. I.; Mancini, L.; Stuermer,
   J.; Abril, M.; Aceituno, J.; Alonso-Floriano, F. J.; Antona, R.;
   Anwand-Heerwart, H.; Arroyo-Torres, B.; Azzaro, M.; Baroch, D.;
   Bauer, F. F.; Becerril, S.; Benitez, D.; Berdinas, Z. M.; Bergond,
   G.; Bluemcke, M.; Brinkmoeller, M.; Cano, J.; Cardenas Vazquez, M. C.;
   Casal, E.; Cifuentes, C.; Claret, A.; Colome, J.; Cortes-Contreras, M.;
   Czesla, S.; Diez-Alonso, E.; Feiz, C.; Fernandez, M.; Ferro, I. M.;
   Fuhrmeister, B.; Galadi-Enriquez, D.; Garcia-Piquer, A.; Garcia
   Vargas, M. L.; Gesa, L.; Gomez Galera, V.; Gonzalez-Peinado, R.;
   Groezinger, U.; Grohnert, S.; Guardia, J.; Guijarro, A.; de Guindos,
   E.; Gutierrez-Soto, J.; Hagen, H. -J.; Hauschildt, P. H.; Hedrosa,
   R. P.; Helmling, J.; Hermelo, I.; Hernandez Arabi, R.; Hernandez
   Castano, L.; Hernandez Hernando, F.; Herrero, E.; Huber, A.; Huke, P.;
   Johnson, E.; de Juan, E.; Kim, M.; Klein, R.; Klueter, J.; Klutsch, A.;
   Lafarga, M.; Lampon, M.; Lara, L. M.; Laun, W.; Lemke, U.; Lenzen,
   R.; Lopez Del Fresno, M.; Lopez-Gonzalez, J.; Lopez-Puertas, M.;
   Lopez Salas, J. F.; Luque, R.; Magan Madinabeitia, H.; Mall, U.;
   Mandel, H.; Marfil, E.; Marin Molina, J. A.; Maroto Fernandez, D.;
   Martin, E. L.; Martin-Ruiz, S.; Marvin, C. J.; Mirabet, E.; Moya,
   A.; Moreno-Raya, M. E.; Nagel, E.; Naranjo, V.; Nortmann, L.; Ofir,
   A.; Oreiro, R.; Palle, E.; Panduro, J.; Pascual, J.; Passegger,
   V. M.; Pedraz, S.; Perez-Calpena, A.; Perez Medialdea, D.; Perger,
   M.; Perryman, M. A. C.; Pluto, M.; Rabaza, O.; Ramon, A.; Rebolo,
   R.; Redondo, P.; Reinhardt, S.; Rhode, P.; Rix, H. -W.; Rodler, F.;
   Rodriguez, E.; Rodriguez Trinidad, A.; Rohlo, R. -R.; Rosich, A.;
   Sadegi, S.; Sanchez-Blanco, E.; Sanchez Carrasco, M. A.; Sanchez-Lopez,
   A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schaefer, S.;
   Schiller, J.; Schoefer, P.; Schweitzer, A.; Solano, E.; Stahl, O.;
   Strachan, J. B. P.; Suarez, J. C.; Tabernero, H. M.; Tala, M.; Tulloch,
   S. M.; Veredas, G.; Vico Linares, J. I.; Vilardel, F.; Wagner, K.;
   Winkler, J.; Woltho, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.
Bibcode: 2017yCat..36090117T
Altcode:
  The two CARMENES spectrographs are grism cross-dispersed, white pupil,
  echelle spectrograph working in quasi-Littrow mode using a two-beam,
  two-slice image slicer. The visible spectrograph covers the wavelength
  range from 0.52um to 1.05um with 61 orders, a resolving power of
  R=94600, and a mean sampling of 2.8 pixels per resolution element. <P
  />The data presented in this paper were taken during the early phase
  of operation of the CARMENES visible-light spectrograph. <P />(8
  data files).

Title: Understanding stellar activity-induced radial velocity jitter
    using simultaneous K2 photometry and HARPS RV measurements
Authors: Oshagh, M.; Santos, N. C.; Figueira, P.; Barros, S. C. C.;
   Donati, J. -F.; Adibekyan, V.; Faria, J. P.; Watson, C. A.; Cegla,
   H. M.; Dumusque, X.; Hébrard, E.; Demangeon, O.; Dreizler, S.;
   Boisse, I.; Deleuil, M.; Bonfils, X.; Pepe, F.; Udry, S.
Bibcode: 2017A&A...606A.107O
Altcode: 2017arXiv170701827O
  One of the best ways to improve our understanding of the stellar
  activity-induced signal in radial velocity (RV) measurements is through
  simultaneous high-precision photometric and RV observations. This is of
  prime importance to mitigate the RV signal induced by stellar activity
  and therefore unveil the presence of low-mass exoplanets. The K2
  Campaign 7 and 8 fields of view were located in the southern hemisphere,
  and provided a unique opportunity to gather unprecedented simultaneous
  high-precision photometric observation with K2 and high-precision RV
  measurements with the HARPS spectrograph to study the relationship
  between photometric variability and RV jitter. We observed nine stars
  with different levels of activity, from quiet to very active. We first
  probed the presence of any meaningful relation between measured RV
  jitter and the simultaneous photometric variation, and also other
  activity indicators (such as BIS, FWHM, log R'<SUB>HK</SUB>, and
  F8) by evaluating the strength and significance of the monotonic
  correlation between RVs and each indicator. We found that for the
  case of very active stars, strong and significant correlations
  exist between almost all the observables and measured RVs; however,
  when we move towards lower activity levels the correlations become
  random, and we could not reach any conclusion regarding the tendency
  of correlations depending on the stellar activity level. Except for
  the F8 whose strong correlation with RV jitter persists over a wide
  range of stellar activity level, and thus our result suggests that F8
  might be a powerful proxy for activity-induced RV jitter over a wide
  range of stellar activity. Moreover, we examine the capability of two
  state-of-the-art modeling techniques, namely the FF' method and SOAP2.0,
  to accurately predict the RV jitter amplitude using the simultaneous
  photometric observation. We found that for the very active stars both
  techniques can predict the amplitude of the RV jitter reasonably well;
  however, at lower activity levels the FF' method underpredicts the RV
  jitter amplitude. <P />RV measurements obtained from the HARPS pipeline
  are only available in electronic form at the CDS via anonymous ftp to
  <A href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://130.79.128.5">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/606/A107">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/606/A107</A>

Title: Hot horizontal branch stars in NGC 288 - effects of diffusion
    and stratification on their atmospheric parameters (Corrigendum)
Authors: Moehler, S.; Dreizler, S.; LeBlanc, F.; Khalack, V.; Michaud,
   G.; Richer, J.; Sweigart, A. V.; Grundahl, F.
Bibcode: 2017A&A...605C...4M
Altcode:
  We found that the script to determine the masses of the stars contains
  two errors. This script and a related one have been used to determine
  masses of globular cluster stars and distances to field stars in 12
  papers published between 1990 and 2014. While the numerical values
  need to be revised none of the conclusions are affected. We provide the
  updated numerical values and figures for all 12 publications here. In
  addition we describe the effects on those refereed publications that
  used the distances to the field stars.

Title: VizieR Online Data Catalog: K2/HARPS measurements for 8 stars
    (Oshagh+, 2017)
Authors: Oshagh, M.; Santos, N. C.; Figueira, P.; Barros, S. C. C.;
   Donati, J. -F.; Adibekyan, V.; Faria, J. P.; Watson, C. A.; Cegla,
   H. M.; Dumusque, X.; Hebrard, E.; Demangeon, O.; Dreizler, S.; Boisse,
   I.; Deleuil, M.; Bonfils, X.; Pepe, F.; Udry, S.
Bibcode: 2017yCat..36060107O
Altcode:
  Tables contain the radial velocity, BIS, FWHM, S-index, and logR'HK
  obtained from the HARPS pipeline for 8 stars in our sample. <P />(2
  data files).

Title: Exploring plausible formation scenarios for the planet
    candidate orbiting Proxima Centauri
Authors: Coleman, G. A. L.; Nelson, R. P.; Paardekooper, S. J.;
   Dreizler, S.; Giesers, B.; Anglada-Escudé, G.
Bibcode: 2017MNRAS.467..996C
Altcode: 2016arXiv160806908C; 2017MNRAS.tmp..175C
  We present a study of four different formation scenarios that
  may be able to explain the origin of the recently announced planet
  ('Proxima b') orbiting Proxima Centauri. The aim is to examine how the
  formation scenarios differ in their predictions for the multiplicity
  of the Proxima system, the water/volatile content of Proxima b and
  its orbital eccentricity, so that these can be tested by future
  observations. A scenario of in situ formation via giant impacts from
  a locally enhanced disc of planetary embryos/planetesimals predicts
  that Proxima b will be in a multiplanet system with a measurably
  finite eccentricity. Assuming that the local solid enhancement needed
  to form a Proxima b analogue arises because of the inwards drift of
  solids in the form of small planetesimals/boulders, this scenario also
  results in Proxima b analogues being only moderately endowed with
  water/volatiles. A scenario in which multiple embryos form, migrate
  and mutually collide within a gas disc results in Proxima b being a
  member of a multiple system, possibly displaying mean-motion resonances,
  but where the constituent members are Ocean planets due to accretion
  occurring mainly outside of the snowline. A scenario in which a single
  accreting embryo forms outside the snowline, and migrates inwards while
  accreting planetesimals/pebbles results in Proxima b being an isolated
  Ocean planet on a circular orbit. A scenario in which Proxima b formed
  via pebble accretion interior to the snowline produces a dry planet on
  a circular orbit. Future observations that characterize the physical
  and orbital properties of Proxima b, and any additional planets in the
  system, will provide valuable insights into the formation history of
  this neighbouring planetary system.

Title: How eclipse time variations, eclipse duration variations,
    and radial velocities can reveal S-type planets in close eclipsing
    binaries
Authors: Oshagh, M.; Heller, R.; Dreizler, S.
Bibcode: 2017MNRAS.466.4683O
Altcode: 2016arXiv161004047O; 2016MNRAS.tmp.1555O
  While about a dozen transiting planets have been found in wide orbits
  around an inner, close stellar binary (so-called P-type planets),
  no planet has yet been detected orbiting only one star (a so-called
  S-type planet) in an eclipsing binary. This is despite a large number
  of eclipsing binary systems discovered with the Kepler telescope. Here
  we propose a new detection method for these S-type planets, which uses a
  correlation between the stellar radial velocities (RVs), eclipse timing
  variations (ETVs) and eclipse duration variations (EDVs). We test the
  capability of this technique by simulating a realistic benchmark system
  and demonstrate its detectability with existing high-accuracy RV and
  photometry instruments. We illustrate that with a small number of RV
  observations, the RV-ETV diagrams allows us to distinguish between
  prograde and retrograde planetary orbits and also the planetary mass
  can be estimated if the stellar cross-correlation functions can be
  disentangled. We also identify a new (though minimal) contribution
  of S-type planets to the Rossiter-McLaughlin effect in eclipsing
  stellar binaries. We finally explore possible detection of exomoons
  around transiting luminous giant planets and find that the precision
  required to detect moons in the RV curves of their host planets is
  of the order of cm s<SUP>-1</SUP> and therefore not accessible with
  current instruments.

Title: Faint-source-star planetary microlensing: the discovery of
    the cold gas-giant planet OGLE-2014-BLG-0676Lb
Authors: Rattenbury, N. J.; Bennett, D. P.; Sumi, T.; Koshimoto,
   N.; Bond, I. A.; Udalski, A.; Shvartzvald, Y.; Maoz, D.; Jørgensen,
   U. G.; Dominik, M.; Street, R. A.; Tsapras, Y.; Abe, F.; Asakura, Y.;
   Barry, R.; Bhattacharya, A.; Donachie, M.; Evans, P.; Freeman, M.;
   Fukui, A.; Hirao, Y.; Itow, Y.; Li, M. C. A.; Ling, C. H.; Masuda,
   K.; Matsubara, Y.; Muraki, Y.; Nagakane, M.; Ohnishi, K.; Oyokawa,
   H.; Saito, To.; Sharan, A.; Sullivan, D. J.; Suzuki, D.; Tristram,
   P. J.; Yonehara, A.; Poleski, R.; Skowron, J.; Mróz, P.; Szymański,
   M. K.; Soszyński, I.; Pietrukowicz, P.; Kozłowski, S.; Ulaczyk, K.;
   Wyrzykowski, Ł.; Friedmann, M.; Kaspi, S.; Alsubai, K.; Browne, P.;
   Andersen, J. M.; Bozza, V.; Calchi Novati, S.; Damerdji, Y.; Diehl,
   C.; Dreizler, S.; Elyiv, A.; Giannini, E.; Hardis, S.; Harpsøe, K.;
   Hinse, T. C.; Liebig, C.; Hundertmark, M.; Juncher, D.; Kains, N.;
   Kerins, E.; Korhonen, H.; Mancini, L.; Martin, R.; Mathiasen, M.;
   Rabus, M.; Rahvar, S.; Scarpetta, G.; Skottfelt, J.; Snodgrass, C.;
   Surdej, J.; Taylor, J.; Tregloan-Reed, J.; Vilela, C.; Wambsganss,
   J.; Williams, A.; D'Ago, G.; Bachelet, E.; Bramich, D. M.; Figuera
   Jaimes, R.; Horne, K.; Menzies, J.; Schmidt, R.; Steele, I. A.
Bibcode: 2017MNRAS.466.2710R
Altcode: 2016arXiv161203511R
  We report the discovery of a planet - OGLE-2014-BLG-0676Lb- via
  gravitational microlensing. Observations for the lensing event were
  made by the following groups: Microlensing Observations in Astrophysics;
  Optical Gravitational Lensing Experiment; Wise Observatory; RoboNET/Las
  Cumbres Observatory Global Telescope; Microlensing Network for
  the Detection of Small Terrestrial Exoplanets; and μ-FUN. All
  analyses of the light-curve data favour a lens system comprising a
  planetary mass orbiting a host star. The most-favoured binary lens
  model has a mass ratio between the two lens masses of (4.78 ±
  0.13) × 10<SUP>-3</SUP>. Subject to some important assumptions,
  a Bayesian probability density analysis suggests the lens system
  comprises a 3.09_{-1.12}^{+1.02} M<SUB>J</SUB> planet orbiting a
  0.62_{-0.22}^{+0.20} M<SUB>⊙</SUB> host star at a deprojected orbital
  separation of 4.40_{-1.46}^{+2.16} au. The distance to the lens system
  is 2.22_{-0.83}^{+0.96} kpc. Planet OGLE-2014-BLG-0676Lb provides
  additional data to the growing number of cool planets discovered
  using gravitational microlensing against which planetary formation
  theories may be tested. Most of the light in the baseline of this
  event is expected to come from the lens and thus high-resolution
  imaging observations could confirm our planetary model interpretation.

Title: Exoplanetary atmospheric sodium revealed by orbital
    motion. Narrow-band transmission spectroscopy of HD 189733b with UVES
Authors: Khalafinejad, S.; von Essen, C.; Hoeijmakers, H. J.; Zhou,
   G.; Klocová, T.; Schmitt, J. H. M. M.; Dreizler, S.; Lopez-Morales,
   M.; Husser, T. -O.; Schmidt, T. O. B.; Collet, R.
Bibcode: 2017A&A...598A.131K
Altcode: 2016arXiv161001610K
  Context. During primary transits, the spectral signatures of exoplanet
  atmospheres can be measured using transmission spectroscopy. We
  can obtain information on the upper atmosphere of these planets by
  investigating the exoplanets' excess sodium absorption in the optical
  region. However, a number of factors can affect the observed sodium
  absorption signature. We present a detailed model correcting for
  systematic biases to yield an accurate depth for the sodium absorption
  in HD 189733b. <BR /> Aims: The goal of this work is to accurately
  measure the atomspheric sodium absorption light curve in HD 189733b,
  correcting for the effects of stellar differential limb-darkening,
  stellar activity, and a "bump" caused by the changing radial velocity
  of the exoplanet. In fact, owing to the high cadence and quality of
  our data, it is the first time that the last feature can be detected
  even by visual inspection. <BR /> Methods: We use 244 high-resolution
  optical spectra taken by the UVES instrument mounted at the VLT. Our
  observations cover a full transit of HD 189733b, with a cadence of
  45 s. To probe the transmission spectrum of sodium we produce excess
  light curves integrating the stellar flux in passbands of 1 Å, 1.5 Å,
  and 3 Å inside the core of each sodium D-line. We model the effects
  of external sources on the excess light curves, which correspond
  to an observed stellar flare beginning close to mid-transit time
  and the wavelength dependent limb-darkening effects. In addition, by
  characterizing the effect of the changing radial velocity and Doppler
  shifts of the planetary sodium lines inside the stellar sodium lines,
  we estimate the depth and width of the exoplanetary sodium feature. <BR
  /> Results: We estimate the shape of the planetary sodium line by
  a Gaussian profile with an equivalent width of 0.0023 ± 0.0010Å,
  thereby confirming the presence of sodium in the atmosphere of HD
  189733b with excess absorption levels of 0.72 ± 0.25%, 0.34 ± 0.11%,
  and 0.20 ± 0.06% for the integration bands of 1 Å, 1.5 Å, and 3 Å,
  respectively. Using the equivalent width of the planetary sodium line,
  we produce a first order estimate of the number density of sodium in
  the exoplanet atmosphere.

Title: The Solar Twin Planet Search. V. Close-in, low-mass planet
    candidates and evidence of planet accretion in the solar twin
    HIP 68468
Authors: Meléndez, Jorge; Bedell, Megan; Bean, Jacob L.; Ramírez,
   Iván; Asplund, Martin; Dreizler, Stefan; Yan, Hong-Liang; Shi,
   Jian-Rong; Lind, Karin; Ferraz-Mello, Sylvio; Galarza, Jhon Yana; dos
   Santos, Leonardo; Spina, Lorenzo; Maia, Marcelo Tucci; Alves-Brito,
   Alan; Monroe, TalaWanda; Casagrande, Luca
Bibcode: 2017A&A...597A..34M
Altcode: 2016arXiv161009067M; 2016A&A...597A..34M
  Context. More than two thousand exoplanets have been discovered to
  date. Of these, only a small fraction have been detected around solar
  twins, which are key stars because we can obtain accurate elemental
  abundances especially for them, which is crucial for studying the
  planet-star chemical connection with the highest precision. <BR />
  Aims: We aim to use solar twins to characterise the relationship between
  planet architecture and stellar chemical composition. <BR /> Methods:
  We obtained high-precision (1 m s<SUP>-1</SUP>) radial velocities
  with the HARPS spectrograph on the ESO 3.6 m telescope at La Silla
  Observatory and determined precise stellar elemental abundances ( 0.01
  dex) using spectra obtained with the MIKE spectrograph on the Magellan
  6.5 m telescope. <BR /> Results: Our data indicate the presence of a
  planet with a minimum mass of 26 ± 4 Earth masses around the solar
  twin HIP 68468. The planet is more massive than Neptune (17 Earth
  masses), but unlike the distant Neptune in our solar system (30 AU),
  HIP 68468c is close-in, with a semi-major axis of 0.66 AU, similar to
  that of Venus. The data also suggest the presence of a super-Earth with
  a minimum mass of 2.9 ± 0.8 Earth masses at 0.03 AU; if the planet is
  confirmed, it will be the fifth least massive radial velocity planet
  candidate discovery to date and the first super-Earth around a solar
  twin. Both isochrones (5.9 ± 0.4 Gyr) and the abundance ratio [Y/Mg]
  (6.4 ± 0.8 Gyr) indicate an age of about 6 billion years. The star
  is enhanced in refractory elements when compared to the Sun, and the
  refractory enrichment is even stronger after corrections for Galactic
  chemical evolution. We determined a nonlocal thermodynamic equilibrium
  Li abundance of 1.52 ± 0.03 dex, which is four times higher than
  what would be expected for the age of HIP 68468. The older age is
  also supported by the low log () (-5.05) and low jitter (&lt;1 m
  s<SUP>-1</SUP>). Engulfment of a rocky planet of 6 Earth masses can
  explain the enhancement in both lithium and the refractory elements. <BR
  /> Conclusions: The super-Neptune planet candidate is too massive for in
  situ formation, and therefore its current location is most likely the
  result of planet migration that could also have driven other planets
  towards its host star, enhancing thus the abundance of lithium and
  refractory elements in HIP 68468. The intriguing evidence of planet
  accretion warrants further observations to verify the existence of
  the planets that are indicated by our data and to better constrain
  the nature of the planetary system around this unique star.

Title: No Evidence for Activity Correlations in the Radial Velocities
    of Kapteyn’s Star
Authors: Anglada-Escudé, G.; Tuomi, M.; Arriagada, P.; Zechmeister,
   M.; Jenkins, J. S.; Ofir, A.; Dreizler, S.; Gerlach, E.; Marvin, C. J.;
   Reiners, A.; Jeffers, S. V.; Butler, R. Paul; Vogt, S. S.; Amado,
   P. J.; Rodríguez-López, C.; Berdiñas, Z. M.; Morin, J.; Crane,
   J. D.; Shectman, S. A.; Díaz, M. R.; Sarmiento, L. F.; Jones, H. R. A.
Bibcode: 2016ApJ...830...74A
Altcode: 2015arXiv150609072A
  Stellar activity may induce Doppler variability at the level of a few
  m s<SUP>-1</SUP> which can then be confused by the Doppler signal of
  an exoplanet orbiting the star. To first order, linear correlations
  between radial velocity measurements and activity indices have been
  proposed to account for any such correlation. The likely presence of two
  super-Earths orbiting Kapteyn’s star was reported in Anglada-Escudé
  et al., but this claim was recently challenged by Robertson et al.,
  who argued for evidence of a rotation period (143 days) at three times
  the orbital period of one of the proposed planets (Kapteyn’s b, P =
  48.6 days) and the existence of strong linear correlations between
  its Doppler signal and activity data. By re-analyzing the data using
  global statistics and model comparison, we show that such a claim is
  incorrect given that (1) the choice of a rotation period at 143 days
  is unjustified, and (2) the presence of linear correlations is not
  supported by the data. We conclude that the radial velocity signals of
  Kapteyn’s star remain more simply explained by the presence of two
  super-Earth candidates orbiting it. We note that analysis of time series
  of activity indices must be executed with the same care as Doppler time
  series. We also advocate for the use of global optimization procedures
  and objective arguments, instead of claims based on residual analyses
  which are prone to biases and incorrect interpretations.

Title: The GTC exoplanet transit spectroscopy survey. IV. Confirmation
    of the flat transmission spectrum of HAT-P-32b
Authors: Nortmann, L.; Pallé, E.; Murgas, F.; Dreizler, S.; Iro,
   N.; Cabrera-Lavers, A.
Bibcode: 2016A&A...594A..65N
Altcode: 2016arXiv160406041N
  We observed the hot Jupiter <ASTROBJ>HAT-P-32b</ASTROBJ> (also known
  as HAT-P-32Ab) to determine its optical transmission spectrum by
  measuring the wavelength-dependent, planet-to-star radius ratios
  in the region between 518-918 nm. We used the OSIRIS instrument at
  the Gran Telescopio CANARIAS (GTC) in long-slit spectroscopy mode,
  placing <ASTROBJ>HAT-P-32</ASTROBJ> and a reference star in the same
  slit and obtaining a time series of spectra covering two transit
  events. Using the best quality data set, we were able to yield 20
  narrowband transit light curves, with each passband spanning a 20
  nm wide interval. After removal of all systematic noise signals and
  light curve modeling, the uncertainties for the resulting radius
  ratios lie between 337 and 972 ppm. The radius ratios show little
  variation with wavelength, suggesting a high altitude cloud layer
  masking any atmospheric features. Alternatively, a strong depletion in
  alkali metals or a much smaller than expected planetary atmospheric
  scale height could be responsible for the lack of atmospheric
  features. Our result of a flat transmission spectrum is consistent
  with a previous ground-based study of the optical spectrum of this
  planet. This agreement between independent results demonstrates
  that ground-based measurements of exoplanet atmospheres can give
  reliable and reproducible results despite the fact that the data
  often is heavily affected by systematic noise as long as the noise
  source is well understood and properly corrected. We also extract
  an optical spectrum of the M-dwarf companion HAT-P-32B. Using
  PHOENIX stellar atmosphere models we determine an effective
  temperature of T<SUB>eff</SUB> = 3187<SUP>+60</SUP><SUB>-71</SUB>
  K, which is slightly colder than previous studies relying only on
  broadband infrared data. <P />The 20 narrowband and white light
  curves are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://130.79.128.5">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/594/A65">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/594/A65</A>

Title: Search for Transits by the Earth Analogue around Proxima
    Centauri
Authors: Jenkins, James; Harrington, Joseph; Challener, Ryan; Rojo,
   Patricio; Kempton, Eliza; Ramirez, Ricardo; Ofir, Aviv; Ribas,
   Ignasi; Kipping, David; Rodriguez-Lopez, Cristina; Dreizler, Stefan;
   Freudenthal, Jantje; Rodriguez-Martinez, Eloy; Anglada-Escude, Guillem
Bibcode: 2016sptz.prop13155J
Altcode:
  We will search for transits of the recently discovered Proxima Centauri
  b. Radial-velocity (RV) data indicate a planet with &gt;1.5 Me (Earth
  masses) and an equilibrium temperature of 230 K (assuming 0.3 albedo and
  complete heat redistribution). Comparing to Earth's 255 K equilibrium
  temperature, the planet may be an excellent candidate to host life,
  and its proximity, at just 1.3 pc, makes it particularly favorable
  for observation, compared to more distant planets. It is thus the
  exoplanet with the highest priority for characterization. Due to the
  red-dwarf star's high activity level, the small size of the planet,
  and the orbital period, optical ground-based transit surveys have not
  achieved the sensitivity needed to detect the transit, but Spitzer
  easily can. The Pale Red Dot project, the planet's discoverers,
  thus request observations that should find any transit with 99%
  confidence, and that will characterize the atmosphere with transits
  at both Spitzer wavelengths.

Title: A terrestrial planet candidate in a temperate orbit around
    Proxima Centauri
Authors: Anglada-Escudé, Guillem; Amado, Pedro J.; Barnes, John;
   Berdiñas, Zaira M.; Butler, R. Paul; Coleman, Gavin A. L.; de La
   Cueva, Ignacio; Dreizler, Stefan; Endl, Michael; Giesers, Benjamin;
   Jeffers, Sandra V.; Jenkins, James S.; Jones, Hugh R. A.; Kiraga,
   Marcin; Kürster, Martin; López-González, María J.; Marvin,
   Christopher J.; Morales, Nicolás; Morin, Julien; Nelson, Richard P.;
   Ortiz, José L.; Ofir, Aviv; Paardekooper, Sijme-Jan; Reiners, Ansgar;
   Rodríguez, Eloy; Rodríguez-López, Cristina; Sarmiento, Luis F.;
   Strachan, John P.; Tsapras, Yiannis; Tuomi, Mikko; Zechmeister, Mathias
Bibcode: 2016Natur.536..437A
Altcode: 2016arXiv160903449A
  At a distance of 1.295 parsecs, the red dwarf Proxima Centauri (α
  Centauri C, GL 551, HIP 70890 or simply Proxima) is the Sun’s closest
  stellar neighbour and one of the best-studied low-mass stars. It has
  an effective temperature of only around 3,050 kelvin, a luminosity of
  0.15 per cent of that of the Sun, a measured radius of 14 per cent of
  the radius of the Sun and a mass of about 12 per cent of the mass of
  the Sun. Although Proxima is considered a moderately active star, its
  rotation period is about 83 days (ref. 3) and its quiescent activity
  levels and X-ray luminosity are comparable to those of the Sun. Here
  we report observations that reveal the presence of a small planet
  with a minimum mass of about 1.3 Earth masses orbiting Proxima with
  a period of approximately 11.2 days at a semi-major-axis distance of
  around 0.05 astronomical units. Its equilibrium temperature is within
  the range where water could be liquid on its surface.

Title: CARMENES: an overview six months after first light
Authors: Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Mundt,
   R.; Reiners, A.; Ribas, I.; Seifert, W.; Abril, M.; Aceituno, J.;
   Alonso-Floriano, F. J.; Anwand-Heerwart, H.; Azzaro, M.; Bauer, F.;
   Barrado, D.; Becerril, S.; Bejar, V. J. S.; Benitez, D.; Berdinas,
   Z. M.; Brinkmöller, M.; Cardenas, M. C.; Casal, E.; Claret, A.;
   Colomé, J.; Cortes-Contreras, M.; Czesla, S.; Doellinger, M.;
   Dreizler, S.; Feiz, C.; Fernandez, M.; Ferro, I. M.; Fuhrmeister,
   B.; Galadi, D.; Gallardo, I.; Gálvez-Ortiz, M. C.; Garcia-Piquer,
   A.; Garrido, R.; Gesa, L.; Gómez Galera, V.; González Hernández,
   J. I.; Gonzalez Peinado, R.; Grözinger, U.; Guàrdia, J.; Guenther,
   E. W.; de Guindos, E.; Hagen, H. -J.; Hatzes, A. P.; Hauschildt,
   P. H.; Helmling, J.; Henning, T.; Hermann, D.; Hernández Arabi, R.;
   Hernández Castaño, L.; Hernández Hernando, F.; Herrero, E.; Huber,
   A.; Huber, K. F.; Huke, P.; Jeffers, S. V.; de Juan, E.; Kaminski,
   A.; Kehr, M.; Kim, M.; Klein, R.; Klüter, J.; Kürster, M.; Lafarga,
   M.; Lara, L. M.; Lamert, A.; Laun, W.; Launhardt, R.; Lemke, U.;
   Lenzen, R.; Llamas, M.; Lopez del Fresno, M.; López-Puertas, M.;
   López-Santiago, J.; Lopez Salas, J. F.; Magan Madinabeitia, H.; Mall,
   U.; Mandel, H.; Mancini, L.; Marin Molina, J. A.; Maroto Fernández,
   D.; Martín, E. L.; Martín-Ruiz, S.; Marvin, C.; Mathar, R. J.;
   Mirabet, E.; Montes, D.; Morales, J. C.; Morales Muñoz, R.; Nagel,
   E.; Naranjo, V.; Nowak, G.; Palle, E.; Panduro, J.; Passegger, V. M.;
   Pavlov, A.; Pedraz, S.; Perez, E.; Pérez-Medialdea, D.; Perger,
   M.; Pluto, M.; Ramón, A.; Rebolo, R.; Redondo, P.; Reffert, S.;
   Reinhart, S.; Rhode, P.; Rix, H. -W.; Rodler, F.; Rodríguez, E.;
   Rodríguez López, C.; Rohloff, R. R.; Rosich, A.; Sanchez Carrasco,
   M. A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schäfer,
   S.; Schiller, J.; Schmidt, C.; Schmitt, J. H. M. M.; Schöfer,
   P.; Schweitzer, A.; Shulyak, D.; Solano, E.; Stahl, O.; Storz, C.;
   Tabernero, H. M.; Tala, M.; Tal-Or, L.; Ulbrich, R. -G.; Veredas, G.;
   Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Winkler, J.; Zapatero
   Osorio, M. -R.; Zechmeister, M.; Ammler-von Eiff, M.; Anglada-Escudé,
   G.; del Burgo, C.; Garcia-Vargas, M. L.; Klutsch, A.; Lizon, J. -L.;
   Lopez-Morales, M.; Ofir, A.; Pérez-Calpena, A.; Perryman, M. A. C.;
   Sánchez-Blanco, E.; Strachan, J. B. P.; Stürmer, J.; Suárez, J. C.;
   Trifonov, T.; Tulloch, S. M.; Xu, W.
Bibcode: 2016SPIE.9908E..12Q
Altcode:
  The CARMENES instrument is a pair of high-resolution (R&gt; 80,000)
  spectrographs covering the wavelength range from 0.52 to 1.71 μm,
  optimized for precise radial velocity measurements. It was installed
  and commissioned at the 3.5m telescope of the Calar Alto observatory
  in Southern Spain in 2015. The first large science program of CARMENES
  is a survey of 300 M dwarfs, which started on Jan 1, 2016. We present
  an overview of all subsystems of CARMENES (front end, fiber system,
  visible-light spectrograph, near-infrared spectrograph, calibration
  units, etalons, facility control, interlock system, instrument control
  system, data reduction pipeline, data flow, and archive), and give an
  overview of the assembly, integration, verification, and commissioning
  phases of the project. We show initial results and discuss further
  plans for the scientific use of CARMENES.

Title: MICADO: first light imager for the E-ELT
Authors: Davies, R.; Schubert, J.; Hartl, M.; Alves, J.; Clénet, Y.;
   Lang-Bardl, F.; Nicklas, H.; Pott, J. -U.; Ragazzoni, R.; Tolstoy, E.;
   Agocs, T.; Anwand-Heerwart, H.; Barboza, S.; Baudoz, P.; Bender, R.;
   Bizenberger, P.; Boccaletti, A.; Boland, W.; Bonifacio, P.; Briegel,
   F.; Buey, T.; Chapron, F.; Cohen, M.; Czoske, O.; Dreizler, S.; Falomo,
   R.; Feautrier, P.; Förster Schreiber, N.; Gendron, E.; Genzel, R.;
   Glück, M.; Gratadour, D.; Greimel, R.; Grupp, F.; Häuser, M.; Haug,
   M.; Hennawi, J.; Hess, H. J.; Hörmann, V.; Hofferbert, R.; Hopp, U.;
   Hubert, Z.; Ives, D.; Kausch, W.; Kerber, F.; Kravcar, H.; Kuijken, K.;
   Lang-Bardl, F.; Leitzinger, M.; Leschinski, K.; Massari, D.; Mei, S.;
   Merlin, F.; Mohr, L.; Monna, A.; Müller, F.; Navarro, R.; Plattner,
   M.; Przybilla, N.; Ramlau, R.; Ramsay, S.; Ratzka, T.; Rhode, P.;
   Richter, J.; Rix, H. -W.; Rodeghiero, G.; Rohloff, R. -R.; Rousset,
   G.; Ruddenklau, R.; Schaffenroth, V.; Schlichter, J.; Sevin, A.; Stuik,
   R.; Sturm, E.; Thomas, J.; Tromp, N.; Turatto, M.; Verdoes-Kleijn, G.;
   Vidal, F.; Wagner, R.; Wegner, M.; Zeilinger, W.; Ziegler, B.; Zins, G.
Bibcode: 2016SPIE.9908E..1ZD
Altcode: 2016arXiv160701954D
  MICADO will equip the E-ELT with a first light capability for
  diffraction limited imaging at near-infrared wavelengths. The
  instrument's observing modes focus on various flavours of imaging,
  including astrometric, high contrast, and time resolved. There is also
  a single object spectroscopic mode optimised for wavelength coverage
  at moderately high resolution. This contribution provides an overview
  of the key functionality of the instrument, outlining the scientific
  rationale for its observing modes. The interface between MICADO and
  the adaptive optics system MAORY that feeds it is summarised. The
  design of the instrument is discussed, focusing on the optics and
  mechanisms inside the cryostat, together with a brief overview of the
  other key sub-systems.

Title: Can stellar activity make a planet seem misaligned?
Authors: Oshagh, M.; Dreizler, S.; Santos, N. C.; Figueira, P.;
   Reiners, A.
Bibcode: 2016A&A...593A..25O
Altcode: 2016arXiv160703134O
  Several studies have shown that the occultation of stellar active
  regions by the transiting planet can generate anomalies in the
  high-precision transit light curves, and these anomalies may lead to
  an inaccurate estimate of the planetary parameters (e.g., the planet
  radius). Since the physics and geometry behind the transit light curve
  and the Rossiter-McLaughlin effect (spectroscopic transit) are the
  same, the Rossiter-McLaughlin observations are expected to be affected
  by the occultation of stellar active regions in a similar way. In
  this paper we perform a fundamental test on the spin-orbit angles
  as derived by Rossiter-McLaughlin measurements, and we examine the
  impact of the occultation of stellar active regions by the transiting
  planet on the spin-orbit angle estimations. Our results show that the
  inaccurate estimation on the spin-orbit angle due to stellar activity
  can be quite significant (up to ~30 deg), particularly for the edge-on,
  aligned, and small transiting planets. Therefore, our results suggest
  that the aligned transiting planets are the ones that can be easily
  misinterpreted as misaligned owing to the stellar activity. In other
  words, the biases introduced by ignoring stellar activity are unlikely
  to be the culprit for the highly misaligned systems.

Title: The Solar Twin Planet Search. IV. The Sun as a typical rotator
    and evidence for a new rotational braking law for Sun-like stars
Authors: dos Santos, Leonardo A.; Meléndez, Jorge; do Nascimento,
   José-Dias; Bedell, Megan; Ramírez, Iván; Bean, Jacob L.; Asplund,
   Martin; Spina, Lorenzo; Dreizler, Stefan; Alves-Brito, Alan;
   Casagrande, Luca
Bibcode: 2016A&A...592A.156D
Altcode: 2016arXiv160606214D
  Context. It is still unclear how common the Sun is when compared to
  other similar stars in regards to some of its physical properties,
  such as rotation. Considering that gyrochronology relations are
  widely used today to estimate ages of stars in the main sequence,
  and that the Sun is used to calibrate it, it is crucial to assess
  whether these procedures are acceptable. <BR /> Aims: We analyze the
  rotational velocities, limited by the unknown rotation axis inclination
  angle, of an unprecedented large sample of solar twins to study the
  rotational evolution of Sun-like stars, and assess whether the Sun is a
  typical rotator. <BR /> Methods: We used high-resolution (R = 115 000)
  spectra obtained with the HARPS spectrograph and the 3.6 m telescope
  at La Silla Observatory. The projected rotational velocities for 81
  solar twins were estimated by line profile fitting with synthetic
  spectra. Macroturbulence velocities were inferred from a prescription
  that accurately reflects their dependence with effective temperature
  and luminosity of the stars. <BR /> Results: Our sample of solar twins
  include some spectroscopic binaries with enhanced rotational velocities,
  and we do not find any nonspectroscopic binaries with unusually high
  rotation velocities. We verified that the Sun does not have a peculiar
  rotation, but the solar twins exhibit rotational velocities that depart
  from the Skumanich relation. <BR /> Conclusions: The Sun is a regular
  rotator when compared to solar twins with a similar age. Additionally,
  we obtain a rotational braking law that better describes the stars in
  our sample (v ∝ t<SUP>-0.6</SUP>) in contrast to previous, often-used
  scalings. <P />Based on observations collected at the European
  Organisation for Astronomical Research in the Southern Hemisphere under
  ESO programs 188.C-0265, 183.D-0729, 292.C-5004, 077.C-0364, 072.C-0488,
  092.C-0721, 093.C-0409, 183.C-0972, 192.C-0852, 091.C-0936, 089.C-0732,
  091.C-0034, 076.C-0155, 185.D-0056, 074.C-0364, 075.C-0332, 089.C-0415,
  60.A-9036, 075.C-0202, 192.C-0224, 090.C-0421 and 088.C-0323.Full
  Table 3 is only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (<A href="http://130.79.128.5">http://130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/592/A156">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/592/A156</A>

Title: VizieR Online Data Catalog: The Solar Twin Planet
    Search. IV. (dos Santos+, 2016)
Authors: Dos Santos, L. A.; Melendez, J.; Do Nascimento, J. -D. Jr;
   Bedell, M.; Ramirez, I.; Bean, J. L.; Asplund, M.; Spina, L.; Dreizler,
   S.; Alves-Brito, A.; Casagrande, L.
Bibcode: 2016yCat..35920156D
Altcode:
  Ages, the measured projected rotational velocities (vsini) and stellar
  parameters of the 81 solar twins and the Sun. The ages of all solar
  twins and stellar parameters for HIP68468 were obtained by Tucci Maia et
  al. (2016A&amp;A...590A..32T). Stellar parameters for the other solar
  twins were obtained by Ramirez et al. (2014A&amp;A...572A..48R). The
  vsini were measured by line profile fitting using red spectra from
  HARPS (R=115000). Macroturbulence velocities were inferred from the
  scaling Eq. 2 in our study. <P />(1 data file).

Title: A Stellar Census in NGC 6397 with MUSE
Authors: Kamann, S.; Husser, T. -O.; Wendt, M.; Bacon, R.; Brinchmann,
   J.; Dreizler, S.; Emsellem, E.; Krajnović, D.; Monreal-Ibero, A.;
   Roth, M. M.; Weilbacher, P. M.; Wisotzki, L.
Bibcode: 2016Msngr.164...18K
Altcode:
  The new and powerful integral-field spectrograph on the VLT, the Multi-
  Unit Spectroscopic Explorer (MUSE), was designed to search for distant
  galaxies to an unprecedented depth, but it is also capable of opening
  new science windows on the Galaxy. To demonstrate this capability,
  the globular cluster NGC 6397 was observed during the commissioning
  of MUSE in August 2014. We outline how the analysis of this unique
  dataset allowed us to assemble the largest spectroscopic sample of
  stars in a globular cluster to date. We also highlight the scientific
  applications that benefit from such MUSE data.

Title: VizieR Online Data Catalog: GTC transit light curves of
    HAT-P-32b (Nortmann+, 2016)
Authors: Nortmann, L.; Palle, E.; Murgas, F.; Dreizler, S.; Iro, N.;
   Cabrera-Lavers, A.
Bibcode: 2016yCat..35940065N
Altcode:
  We provide two transit light curves of the hot Jupiter HAT-P-32b
  obtained on the nights of 2012/09/15 and 2012/09/30 using the OSIRIS
  instrument at the 10.4-m GTC telescope. The data was obtained by using
  OSIRIS in broad slit spectroscopy mode and covering the wavelength
  region between 518nm-918nm. For the night of 2012/09/30 we further
  provide twenty narrowband light curves which were created by summing
  the flux over 20-nm-wide channels instead over the whole wavelength
  region. We provide several auxiliary parameters of the observations
  which we have used to correct the data from correlated noise. These
  auxiliary parameters are the position drift of the stars on the CCD
  detector in spatial and dispersion direction, air mass and seeing
  (FWHM). <P />(23 data files).

Title: Erratum: A detailed census of variable stars in the globular
    cluster NGC 6333 (M9) from CCD differential photometry
Authors: Arellano Ferro, A.; Bramich, D. M.; Figuera Jaimes, R.;
   Giridhar, Sunetra; Kains, N.; Kuppuswamy, K.; Jørgensen, U. G.;
   Alsubai, K. A.; Andersen, J. M.; Bozza, V.; Browne, P.; Calchi Novati,
   S.; Damerdji, Y.; Diehl, C.; Dominik, M.; Dreizler, S.; Elyiv, A.;
   Giannini, E.; Harpsøe, K.; Hessman, F. V.; Hinse, T. C.; Hundertmark,
   M.; Juncher, D.; Kerins, E.; Korhonen, H.; Liebig, C.; Mancini,
   L.; Mathiasen, M.; Penny, M. T.; Rabus, M.; Rahvar, S.; Ricci, D.;
   Scarpetta, G.; Skottfelt, J.; Snodgrass, C.; Southworth, J.; Surdej,
   J.; Tregloan-Reed, J.; Vilela, C.; Wertz, O.; Mindstep Consortium
Bibcode: 2016MNRAS.458.1188A
Altcode: 2016MNRAS.tmp..123F
  No abstract at ADS

Title: MUSE crowded field 3D spectroscopy of over 12 000 stars in
    the globular cluster NGC 6397. II. Probing the internal dynamics
    and the presence of a central black hole
Authors: Kamann, S.; Husser, T. -O.; Brinchmann, J.; Emsellem, E.;
   Weilbacher, P. M.; Wisotzki, L.; Wendt, M.; Krajnović, D.; Roth,
   M. M.; Bacon, R.; Dreizler, S.
Bibcode: 2016A&A...588A.149K
Altcode: 2016arXiv160201643K
  We present a detailed analysis of the kinematics of the Galactic
  globular cluster <ASTROBJ>NGC 6397</ASTROBJ> based on more than ~18 000
  spectra obtained with the novel integral field spectrograph MUSE. While
  <ASTROBJ>NGC 6397</ASTROBJ> is often considered a core collapse cluster,
  our analysis suggests a flattening of the surface brightness profile
  at the smallest radii. Although it is among the nearest globular
  clusters, the low velocity dispersion of <ASTROBJ>NGC 6397</ASTROBJ>
  of &lt; 5 km s<SUP>-1</SUP> imposes heavy demands on the quality of the
  kinematical data. We show that despite its limited spectral resolution,
  MUSE reaches an accuracy of 1 km s<SUP>-1</SUP> in the analysis of
  stellar spectra. We find slight evidence for a rotational component
  in the cluster and the velocity dispersion profile that we obtain
  shows a mild central cusp. To investigate the nature of this feature,
  we calculate spherical Jeans models and compare these models to our
  kinematical data. This comparison shows that if a constant mass-to-light
  ratio is assumed, the addition of an intermediate-mass black hole
  with a mass of 600 M<SUB>⊙</SUB> brings the model predictions into
  agreement with our data, and therefore could be at the origin of the
  velocity dispersion profile. We further investigate cases with varying
  mass-to-light ratios and find that a compact dark stellar component can
  also explain our observations. However, such a component would closely
  resemble the black hole from the constant mass-to-light ratio models as
  this component must be confined to the central ~5″ of the cluster and
  must have a similar mass. Independent constraints on the distribution
  of stellar remnants in the cluster or kinematic measurements at the
  highest possible spatial resolution should be able to distinguish
  the two alternatives. <P />Based on observations obtained at the Very
  Large Telescope (VLT) of the European Southern Observatory, Paranal,
  Chile (ESO Programme ID 60.A-9100(C))

Title: MUSE crowded field 3D spectroscopy of over 12 000 stars in
    the globular cluster NGC 6397. I. The first comprehensive HRD of a
    globular cluster
Authors: Husser, Tim-Oliver; Kamann, Sebastian; Dreizler, Stefan;
   Wendt, Martin; Wulff, Nina; Bacon, Roland; Wisotzki, Lutz; Brinchmann,
   Jarle; Weilbacher, Peter M.; Roth, Martin M.; Monreal-Ibero, Ana
Bibcode: 2016A&A...588A.148H
Altcode: 2016arXiv160201649H
  <BR /> Aims: We demonstrate the high multiplex advantage of crowded
  field 3D spectroscopy with the new integral field spectrograph MUSE
  by means of a spectroscopic analysis of more than 12 000 individual
  stars in the globular cluster NGC 6397. <BR /> Methods: The stars
  are deblended with a point spread function fitting technique, using a
  photometric reference catalogue from HST as prior, including relative
  positions and brightnesses. This catalogue is also used for a first
  analysis of the extracted spectra, followed by an automatic in-depth
  analysis via a full-spectrum fitting method based on a large grid
  of PHOENIX spectra. <BR /> Results: We analysed the largest sample
  so far available for a single globular cluster of 18 932 spectra
  from 12 307 stars in <ASTROBJ>NGC 6397</ASTROBJ>. We derived a mean
  radial velocity of v<SUB>rad</SUB> = 17.84 ± 0.07 km s<SUP>-1</SUP>
  and a mean metallicity of [Fe/H] = -2.120 ± 0.002, with the latter
  seemingly varying with temperature for stars on the red giant branch
  (RGB). We determine T<SUB>eff</SUB> and [Fe/H] from the spectra,
  and log g from HST photometry. This is the first very comprehensive
  Hertzsprung-Russell diagram (HRD) for a globular cluster based on the
  analysis of several thousands of stellar spectra, ranging from the main
  sequence to the tip of the RGB. Furthermore, two interesting objects
  were identified; one is a post-AGB star and the other is a possible
  millisecond-pulsar companion. <P />Data products are available at <A
  href="http://muse-vlt.eu/science">http://muse-vlt.eu/science</A>Based on
  observations obtained at the Very Large Telescope (VLT) of the European
  Southern Observatory, Paranal, Chile (ESO Programme ID 60.A-9100(C)).

Title: Transmission Spectroscopy of HAT-P-32Ab with GTC/OSIRIS
Authors: Nortmann, Lisa; Pallé, Enric; Murgas, Felipe; Dreizler,
   Stefan; Iro, Nicolas; Cabrera-Lavers, Antonio
Bibcode: 2015ESS.....311120N
Altcode:
  I will present one of the latest results of our GTC exoplanet transit
  spectroscopy survey. Over the last years our group has obtained
  ground-based optical (538 nm - 918 nm) spectrophotometric transit
  observations for several hot Jupiters including HAT-P-32Ab using
  the OSIRIS (Optical System for Imaging and low Resolution Integrated
  Spectroscopy) instrument at the Spanish 10-meter telescope GTC.I will
  discuss the source, nature and proper correction of instrument specific
  systematic noise we found to affect our data. After its correction,
  we were able to yield high quality results with a precision between
  482 and 1703 ppm depending on the wavelength channel. We measure a
  flat optical transmission spectrum for HAT-P-32Ab, consistent with the
  results of Gibson et al. (2013, MNRAS, 436, 2974) obtained with GMOS
  at Gemini-North. This independent reproduction of consistent results
  re-establishes faith in the reliability of ground-based transmission
  spectroscopy and emphasizes the high potential of OSIRIS at the GTC
  as a tool to complement current and future space-based observations.

Title: A temperature inversion in WASP-33b? Large Binocular Telescope
    occultation data confirm significant thermal flux at short wavelengths
Authors: von Essen, C.; Mallonn, M.; Albrecht, S.; Antoci, V.; Smith,
   A. M. S.; Dreizler, S.; Strassmeier, K. G.
Bibcode: 2015A&A...584A..75V
Altcode: 2015arXiv150705963V
  We observed a secondary eclipse of WASP-33 b quasi-simultaneously
  in the optical (~0.55 μm) and the near-infrared (~1.05 μm) using
  the 2×8.4 m Large Binocular Telescope. WASP-33 is a δ Scuti star
  pulsating with periods comparable to the eclipse duration, making
  the determination of the eclipse depth challenging. We use previously
  determined oscillation frequencies to model and remove the pulsation
  signal from the light curves, isolating the secondary eclipse. The
  determined eclipse depth is ΔF = 1.03 ± 0.34 parts per thousand,
  corresponding to a brightness temperature of T<SUB>B</SUB> = 3398 ± 302
  K. Combining previously published data with our new measurement we find
  the equilibrium temperature of WASP-33 b to be T<SUB>B</SUB> = 3358 ±
  165 K. We compare all existing eclipse data to a blackbody spectrum,
  to a carbon-rich non-inverted model and to a solar composition model
  with an inverted temperature structure. We find that current available
  data on WASP-33 b's atmosphere can be best represented by a simple
  blackbody emission, without the need for more sophisticated atmospheric
  models with temperature inversions. Although our data cannot rule out
  models with or without a temperature inversion, they do confirm a high
  brightness temperature for the planet at short wavelengths. WASP-33 b
  is one of the hottest exoplanets known till date, and its equilibrium
  temperature is consistent with rapid reradiation of the absorbed stellar
  light and a low albedo. <P />The LBT is an international collaboration
  among institutions in the United States, Italy and Germany. LBT
  Corporation partners are: The University of Arizona on behalf of the
  Arizona university system; Instituto Nazionale di Astrofisica, Italy;
  LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck
  Society, the Leibniz-Institute for Astrophysics Potsdam, and Heidelberg
  University; The Ohio State University, and The Research Corporation,
  on behalf of The University of Notre Dame, University of Minnesota and
  University of Virginia.Appendix A is available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201526202/olm">http://www.aanda.org</A>

Title: Planets around post-common envelope binaries
Authors: Dreizler, Stefan; Beuermann, Klaus; Hessman, Frederic;
   Husser, Tim-Oliver
Bibcode: 2015ESS.....311702D
Altcode:
  The timing method enables to search planets in extreme conditions,
  e.g. as companion to pulsars or as planets in post-common envelope
  binaries (PCEB). In both cases, the planetary systems have experience
  a dramatic evolution of the primary star.Eclipse time variations in
  PCEBs with white dwarfs and subdwarf-B stars as primaries have been
  interpreted as signatures from circumbinary planets and planetary
  systems. Several of these interpretations have been questioned later
  on, either due to dynamical instability of the proposed planetary
  systems or due to non-detection of the proposed companions. We will
  give an overview of our long-term monitoring of PCEB systems and the
  modelling in terms of Keplerian and Newtonian planetary orbits in
  order to assess the circumbinary planet scenario for these systems. We
  discuss the implications for the first-generation or second-generatoin
  planet scenario for these potential planets around these evolved stars.

Title: Using Solar Twins to Explore the Planet-Star Connection with
    Unparallelled Precision
Authors: Meléndez, J.; Bean, J. L.; Bedell, M.; Ramírez, I.; Asplund,
   M.; Dreizler, S.; Alves-Brito, A.; Spina, L.; Casagrande, L.; Monroe,
   T.; Maia, M. T.; Freitas, F.
Bibcode: 2015Msngr.161...28M
Altcode:
  This year marks the 20th anniversary of the first definitive
  detection of an exoplanet orbiting a Sun-like star by Mayor and
  Queloz (1995). Almost 2000 exoplanets have been discovered since this
  breakthrough, but many fundamental questions remain open despite the
  enormous progress: How common are analogues of the Solar System? How
  do planets form and evolve? What is the relationship between stars and
  planets? We are observing stars that are near-perfect matches to the
  Sun to provide new insights into the above questions, thus exploring
  the planet-star connection with unprecedented precision.

Title: The Solar Twin Planet Search. II. A Jupiter twin around a
    solar twin
Authors: Bedell, M.; Meléndez, J.; Bean, J. L.; Ramírez, I.; Asplund,
   M.; Alves-Brito, A.; Casagrande, L.; Dreizler, S.; Monroe, T.; Spina,
   L.; Tucci Maia, M.
Bibcode: 2015A&A...581A..34B
Altcode: 2015arXiv150703998B
  Context. With high-precision radial velocity surveys reaching a
  sufficiently long time baseline, the domain of long-period planet
  detections has recently opened up. The search for Jupiter-like planets
  is especially important if we wish to investigate the prevalence
  of solar system analogs, but their detection is complicated by the
  existence of stellar activity cycles on similar timescales. Radial
  velocity data with sufficiently long-term instrumental precision and
  robust methods of diagnosing activity are crucial to the detection of
  extrasolar Jupiters. <BR /> Aims: Through our HARPS survey for planets
  around solar twin stars, we have identified a promising Jupiter twin
  candidate around the star HIP11915. We characterize this Keplerian
  signal and investigate its potential origins in stellar activity. <BR
  /> Methods: We carry out a Markov chain Monte Carlo (MCMC) analysis of
  the radial velocity data. To examine the signal's origin, we employ
  a variety of statistical tests using activity diagnostics such as
  the Ca II H and K lines and line asymmetry tracers. <BR /> Results:
  Our analysis indicates that HIP11915 hosts a Jupiter-mass planet with
  a 3800-day orbital period and low eccentricity. Although we cannot
  definitively rule out an activity cycle interpretation, we find that a
  planet interpretation is more likely based on a joint analysis of radial
  velocity and activity index data. <BR /> Conclusions: The challenges of
  long-period radial velocity signals addressed in this paper are critical
  for the ongoing discovery of Jupiter-like exoplanets. If planetary in
  nature, the signal investigated here represents a very close analog to
  the solar system in terms of both Sun-like host star and Jupiter-like
  planet. <P />Table 3 and Fig. 5 are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201525748/olm">http://www.aanda.org</A>

Title: Spectroscopic Surface Brightness Fluctuations: a new method
    to analyze the stellar population content of galaxies
Authors: Walcher, C. Jakob; Mitzkus, Martin; Roth, Martin; Dreizler,
   Stefan
Bibcode: 2015IAUGA..2194398W
Altcode:
  Rare luminous phases of stellar evolution are important scientific
  targets because our understanding of them strongly influences what
  physical parameters we can recover from integrated spectra. (TP-)AGB
  stars have been the focus of much attention over the last decade,
  as their flux contribution to the spectra of intermediate age stellar
  populations is highly uncertain. We here present a new approach to this
  problem, which relies on Surface Brightness Fluctuations (SBF) with high
  spectral resolution - a domain that is opening up for the first time
  thanks to the new MUSE integral field unit at the VLT. We will present
  the SSBF technique, illustrating its power through simulations. We
  will then present the analysis of dedicated data obtained with MUSE,
  providing new benchmark constraints on the luminous stellar population
  of entire galaxies.

Title: Spectroscopic Surface Brightness Fluctuations: Amplifying
    Bright Stars in Unresolved Stellar Populations
Authors: Mitzkus, M.; Dreizler, S.; Roth, M. M.
Bibcode: 2015ASPC..497..491M
Altcode:
  We report on our early-stage efforts to resolve the Surface Brightness
  Fluctuations (SBFs) in the spectral dimension. Combining the diagnostic
  power of SBFs with the physical information content of spectra
  seems a tempting possibility to gain new insights into the bright
  stars in unresolved stellar populations. The new VLT integral field
  spectrograph MUSE is the first instrument that enables spectroscopic
  SBFs observationally.

Title: Planet formation in post-common-envelope binaries
Authors: Schleicher, D. R. G.; Dreizler, S.; Völschow, M.; Banerjee,
   R.; Hessman, F. V.
Bibcode: 2015AN....336..458S
Altcode: 2015arXiv150101656S
  To understand the evolution of planetary systems, it is important to
  investigate planets in highly evolved stellar systems, and to explore
  the implications of their observed properties with respect to potential
  formation scenarios. Observations suggest the presence of giant planets
  in post-common-envelope binaries (PCEBs). A particularly well-studied
  system with planetary masses of 1.7 M_J and 7.0 M_J is NN Ser. We
  show here that a pure first-generation scenario where the planets
  form before the common envelope (CE) phase and the orbits evolve due
  to the changes in the gravitational potential is inconsistent with
  the current data. We propose a second-generation scenario where the
  planets are formed from the material that is ejected during the CE,
  which may naturally explain the observed planetary masses. In addition,
  hybrid scenarios where the planets form before the CE and evolve due
  to the accretion of the ejected gas appear as a realistic possibility.

Title: Periodicity and eclipse minima timing of CM Draconis.
Authors: Vázquez-Martín, S.; Deeg, H. J.; Dreizler, S.; von Essen,
   C.; Kozhevnikov, V. P.
Bibcode: 2015hsa8.conf..618V
Altcode:
  Periodic deviations from a linear ephemeris of a binary star's eclipses
  can indicate the presence of a third body in orbit around both. Hints
  for such companion around the M4.5/M4.5 binary CMDra were published
  by Deeg et al. (2008). The assignment of a planet in the CMDra system
  can however only be accepted if the earlier observed periodicity
  trends can be verified through further observations over several
  years. For eclipsing binary stars of low mass, the method of eclipse
  minimum timing allows one to set mass limits for the detection of a
  third body. Deeg et al. (2008) concluded that the two possibilities
  for the source of CMDra's timing variations that remain valid are
  a planet of a few Jupiter masses on a two decade-long orbit, or an
  object on a century-to-millenium long orbit with masses 1.5M_J &lt;
  M_{p} &lt; 0.1M_{⊙}. However, they concluded that it is necessary
  to do continued observations of the timing of CMDra's eclipses to be
  decisive regarding the continued viability of the sinusoidal-fit-model,
  and hence, about the validity of a Jovian-type planet in a circumbinary
  orbiting around the system. Here we update the analysis of Deeg et
  al. (2008), including further data presented in Morales et al. (2009r)
  and new observations taken at Ural Observatory (2008-2013). Eclipse
  minimum times were obtained using the Kwee-van-Woerden method.

Title: OGLE-2011-BLG-0265Lb: A Jovian Microlensing Planet Orbiting
    an M Dwarf
Authors: Skowron, J.; Shin, I. -G.; Udalski, A.; Han, C.; Sumi,
   T.; Shvartzvald, Y.; Gould, A.; Dominis Prester, D.; Street,
   R. A.; Jørgensen, U. G.; Bennett, D. P.; Bozza, V.; Szymański,
   M. K.; Kubiak, M.; Pietrzyński, G.; Soszyński, I.; Poleski, R.;
   Kozłowski, S.; Pietrukowicz, P.; Ulaczyk, K.; Wyrzykowski, Ł.; OGLE
   Collaboration; Abe, F.; Bhattacharya, A.; Bond, I. A.; Botzler, C. S.;
   Freeman, M.; Fukui, A.; Fukunaga, D.; Itow, Y.; Ling, C. H.; Koshimoto,
   N.; Masuda, K.; Matsubara, Y.; Muraki, Y.; Namba, S.; Ohnishi, K.;
   Philpott, L. C.; Rattenbury, N.; Saito, T.; Sullivan, D. J.; Suzuki,
   D.; Tristram, P. J.; Yock, P. C. M.; MOA Collaboration; Maoz, D.;
   Kaspi, S.; Friedmann, M.; Wise Group; Almeida, L. A.; Batista, V.;
   Christie, G.; Choi, J. -Y.; DePoy, D. L.; Gaudi, B. S.; Henderson, C.;
   Hwang, K. -H.; Jablonski, F.; Jung, Y. K.; Lee, C. -U.; McCormick,
   J.; Natusch, T.; Ngan, H.; Park, H.; Pogge, R. W.; Yee, J. C.;
   μFUN Collaboration; Albrow, M. D.; Bachelet, E.; Beaulieu, J. -P.;
   Brillant, S.; Caldwell, J. A. R.; Cassan, A.; Cole, A.; Corrales, E.;
   Coutures, Ch.; Dieters, S.; Donatowicz, J.; Fouqué, P.; Greenhill,
   J.; Kains, N.; Kane, S. R.; Kubas, D.; Marquette, J. -B.; Martin,
   R.; Menzies, J.; Pollard, K. R.; Ranc, C.; Sahu, K. C.; Wambsganss,
   J.; Williams, A.; Wouters, D.; PLANET Collaboration; Tsapras, Y.;
   Bramich, D. M.; Horne, K.; Hundertmark, M.; Snodgrass, C.; Steele,
   I. A.; RoboNet Collaboration; Alsubai, K. A.; Browne, P.; Burgdorf,
   M. J.; Calchi Novati, S.; Dodds, P.; Dominik, M.; Dreizler, S.; Fang,
   X. -S.; Gu, C. -H.; Hardis; Harpsøe, K.; Hessman, F. V.; Hinse, T. C.;
   Hornstrup, A.; Jessen-Hansen, J.; Kerins, E.; Liebig, C.; Lund, M.;
   Lundkvist, M.; Mancini, L.; Mathiasen, M.; Penny, M. T.; Rahvar, S.;
   Ricci, D.; Scarpetta, G.; Skottfelt, J.; Southworth, J.; Surdej, J.;
   Tregloan-Reed, J.; Wertz, O.; MiNDSTEp Consortium
Bibcode: 2015ApJ...804...33S
Altcode: 2014arXiv1410.8252S
  We report the discovery of a Jupiter-mass planet orbiting an M-dwarf
  star that gave rise to the microlensing event OGLE-2011-BLG-0265. Such
  a system is very rare among known planetary systems and thus the
  discovery is important for theoretical studies of planetary formation
  and evolution. High-cadence temporal coverage of the planetary
  signal, combined with extended observations throughout the event,
  allows us to accurately model the observed light curve. However, the
  final microlensing solution remains degenerate, yielding two possible
  configurations of the planet and the host star. In the case of the
  preferred solution, the mass of the planet is {{M}<SUB>p</SUB>}=0.9+/-
  0.3 {{M}<SUB>J</SUB>}, and the planet is orbiting a star with a mass
  M=0.22+/- 0.06 {{M}<SUB>⊙ </SUB>}. The second possible configuration
  (2σ away) consists of a planet with {{M}<SUB>p</SUB>}=0.6+/- 0.3
  {{M}<SUB>J</SUB>} and host star with M=0.14+/- 0.06 {{M}<SUB>⊙
  </SUB>}. The system is located in the Galactic disk 3-4 kpc toward
  the Galactic bulge. In both cases, with an orbit size of 1.5-2.0 AU,
  the planet is a “cold Jupiter”—located well beyond the “snow
  line” of the host star. Currently available data make the secure
  selection of the correct solution difficult, but there are prospects
  for lifting the degeneracy with additional follow-up observations in
  the future, when the lens and source star separate.

Title: VizieR Online Data Catalog: MUSE 3D view of HDF-S (Bacon+,
    2015)
Authors: Bacon, R.; Brinchmann, J.; Richard, J.; Contini, T.; Drake,
   A.; Franx, M.; Tacchella, S.; Vernet, J.; Wisotzki, L.; Blaizot, J.;
   Bouche, N.; Bouwens, R.; Cantalupo, S.; Carollo, C. M.; Carton, D.;
   Caruana, J.; Clement, B.; Dreizler, S.; Epinat, B.; Guiderdoni, B.;
   Herenz, C.; Husser, T. -O.; Kamann, S.; Kerutt, J.; Kollatschny, W.;
   Krajnovic, D.; Lilly, S.; Martinsson, T.; Michel-Dansac, L.; Patricio,
   V.; Schaye, J.; Shirazi, M.; Soto, K.; Soucail, G.; Steinmetz, M.;
   Urrutia, T.; Weilbacher, P.; de Zeeuw, T.
Bibcode: 2015yCat..35750075B
Altcode:
  The HDFS was observed during six nights in July 25-29, 31 and August
  2, 3 2014 of the last commissioning run of MUSE. We used the nominal
  wavelength range (4750-9300Å) and performed a series of exposures of
  30min each. <P />(3 data files).

Title: VizieR Online Data Catalog: MUSE 3D view of HDF-S (Bacon+,
    2015)
Authors: Bacon, R.; Brinchmann, J.; Richard, J.; Contini, T.; Drake,
   A.; Franx, M.; Tacchella, S.; Vernet, J.; Wisotzki, L.; Blaizot, J.;
   Bouche, N.; Bouwens, R.; Cantalupo, S.; Carollo, C. M.; Carton, D.;
   Caruana, J.; Clement, B.; Dreizler, S.; Epinat, B.; Guiderdoni, B.;
   Herenz, C.; Husser, T. -O.; Kamann, S.; Kerutt, J.; Kollatschny, W.;
   Krajnovic, D.; Lilly, S.; Martinsson, T.; Michel-Dansac, L.; Patricio,
   V.; Schaye, J.; Shirazi, M.; Soto, K.; Soucail, G.; Steinmetz, M.;
   Urrutia, T.; Weilbacher, P.; de Zeeuw, T.
Bibcode: 2015yCat..35759075B
Altcode:
  The HDFS was observed during six nights in July 25-29, 31 and August
  2, 3 2014 of the last commissioning run of MUSE. We used the nominal
  wavelength range (4750-9300Å) and performed a series of exposures of
  30min each. <P />(3 data files).

Title: The MUSE 3D view of the Hubble Deep Field South
Authors: Bacon, R.; Brinchmann, J.; Richard, J.; Contini, T.; Drake,
   A.; Franx, M.; Tacchella, S.; Vernet, J.; Wisotzki, L.; Blaizot, J.;
   Bouché, N.; Bouwens, R.; Cantalupo, S.; Carollo, C. M.; Carton, D.;
   Caruana, J.; Clément, B.; Dreizler, S.; Epinat, B.; Guiderdoni, B.;
   Herenz, C.; Husser, T. -O.; Kamann, S.; Kerutt, J.; Kollatschny, W.;
   Krajnovic, D.; Lilly, S.; Martinsson, T.; Michel-Dansac, L.; Patricio,
   V.; Schaye, J.; Shirazi, M.; Soto, K.; Soucail, G.; Steinmetz, M.;
   Urrutia, T.; Weilbacher, P.; de Zeeuw, T.
Bibcode: 2015A&A...575A..75B
Altcode: 2014arXiv1411.7667B
  We observed Hubble Deep Field South with the new panoramic
  integral-field spectrograph MUSE that we built and have just
  commissioned at the VLT. The data cube resulting from 27 h of
  integration covers one arcmin<SUP>2</SUP> field of view at an
  unprecedented depth with a 1σ emission-line surface brightness
  limit of 1 × 10<SUP>-19</SUP> erg s<SUP>-1</SUP> cm<SUP>-2</SUP>
  arcsec<SUP>-2</SUP>, and contains ~90 000 spectra. We present the
  combined and calibrated data cube, and we performed a first-pass
  analysis of the sources detected in the Hubble Deep Field South
  imaging. We measured the redshifts of 189 sources up to a magnitude
  I<SUB>814</SUB> = 29.5, increasing the number of known spectroscopic
  redshifts in this field by more than an order of magnitude. We
  also discovered 26 Lyα emitting galaxies that are not detected
  in the HST WFPC2 deep broad-band images. The intermediate spectral
  resolution of 2.3 Å allows us to separate resolved asymmetric Lyα
  emitters, [O ii]3727 emitters, and C iii]1908 emitters, and the broad
  instantaneous wavelength range of 4500 Å helps to identify single
  emission lines, such as [O iii]5007, Hβ, and Hα, over a very wide
  redshift range. We also show how the three-dimensional information of
  MUSE helps to resolve sources that are confused at ground-based image
  quality. Overall, secure identifications are provided for 83% of the
  227 emission line sources detected in the MUSE data cube and for 32% of
  the 586 sources identified in the HST catalogue. The overall redshift
  distribution is fairly flat to z = 6.3, with a reduction between z =
  1.5 to 2.9, in the well-known redshift desert. The field of view of
  MUSE also allowed us to detect 17 groups within the field. We checked
  that the number counts of [O ii]3727 and Lyα emitters are roughly
  consistent with predictions from the literature. Using two examples, we
  demonstrate that MUSE is able to provide exquisite spatially resolved
  spectroscopic information on the intermediate-redshift galaxies
  present in the field. Thisunique data set can be used for a wide
  range of follow-up studies. We release the data cube, the associated
  products, and the source catalogue with redshifts, spectra, and
  emission-line fluxes. <P />Advanced data products are available at <A
  href="http://muse-vlt.eu/science">http://muse-vlt.eu/science</A>. Based
  on observations made with ESO telescopes at
  the La Silla Paranal Observatory under program ID
  60.A-9100(C).Appendices are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201425419/olm">http://www.aanda.org</A>

Title: The Solar Twin Planet Search. I. Fundamental parameters of
    the stellar sample
Authors: Ramírez, I.; Meléndez, J.; Bean, J.; Asplund, M.; Bedell,
   M.; Monroe, T.; Casagrande, L.; Schirbel, L.; Dreizler, S.; Teske,
   J.; Tucci Maia, M.; Alves-Brito, A.; Baumann, P.
Bibcode: 2014A&A...572A..48R
Altcode: 2014arXiv1408.4130R
  Context. We are carrying out a search for planets around a sample
  of solar twin stars using the HARPS spectrograph. The goal of this
  project is to exploit the advantage offered by solar twins to obtain
  chemical abundances of unmatched precision. This survey will enable
  new studies of the stellar composition - planet connection. <BR />
  Aims: We determine the fundamental parameters of the 88 solar twin
  stars that have been chosen as targets for our experiment. <BR />
  Methods: We used the MIKE spectrograph on the Magellan Clay Telescope
  to acquire high resolution, high signal-to-noise ratio spectra of
  our sample stars. We measured the equivalent widths of iron lines
  and used strict differential excitation/ionization balance analysis
  to determine atmospheric parameters of unprecedented internal
  precision: σ(T<SUB>eff</SUB>) = 7 K, σ(log g) = 0.019, σ( [Fe/H]
  ) = 0.006 dex, σ(v<SUB>t</SUB>) = 0.016 km s<SUP>-1</SUP>. Reliable
  relative ages and highly precise masses were then estimated using
  theoretical isochrones. <BR /> Results: The spectroscopic parameters
  we derived are in good agreement with those measured using other
  independent techniques. There is even better agreement if the
  sample is restricted to those stars with the most internally precise
  determinations of stellar parameters in every technique involved. The
  root-mean-square scatter of the differences seen is fully compatible
  with the observational errors, demonstrating, as assumed thus far,
  that systematic uncertainties in the stellar parameters are negligible
  in the study of solar twins. We find a tight activity-age relation
  for our sample stars, which validates the internal precision of our
  dating method. Furthermore, we find that the solar cycle is perfectly
  consistent both with this trend and its star-to-star scatter. <BR />
  Conclusions: We present the largest sample of solar twins analyzed
  homogeneously using high quality spectra. The fundamental parameters
  derived from this work will be employed in subsequent work that aims to
  explore the connections between planet formation and stellar chemical
  composition. <P />Tables 2-4 are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201424244/olm">http://www.aanda.org</A>

Title: The PLATO 2.0 mission
Authors: Rauer, H.; Catala, C.; Aerts, C.; Appourchaux, T.; Benz,
   W.; Brandeker, A.; Christensen-Dalsgaard, J.; Deleuil, M.; Gizon,
   L.; Goupil, M. -J.; Güdel, M.; Janot-Pacheco, E.; Mas-Hesse,
   M.; Pagano, I.; Piotto, G.; Pollacco, D.; Santos, Ċ.; Smith, A.;
   Suárez, J. -C.; Szabó, R.; Udry, S.; Adibekyan, V.; Alibert, Y.;
   Almenara, J. -M.; Amaro-Seoane, P.; Eiff, M. Ammler-von; Asplund, M.;
   Antonello, E.; Barnes, S.; Baudin, F.; Belkacem, K.; Bergemann, M.;
   Bihain, G.; Birch, A. C.; Bonfils, X.; Boisse, I.; Bonomo, A. S.;
   Borsa, F.; Brandão, I. M.; Brocato, E.; Brun, S.; Burleigh, M.;
   Burston, R.; Cabrera, J.; Cassisi, S.; Chaplin, W.; Charpinet, S.;
   Chiappini, C.; Church, R. P.; Csizmadia, Sz.; Cunha, M.; Damasso, M.;
   Davies, M. B.; Deeg, H. J.; Díaz, R. F.; Dreizler, S.; Dreyer, C.;
   Eggenberger, P.; Ehrenreich, D.; Eigmüller, P.; Erikson, A.; Farmer,
   R.; Feltzing, S.; de Oliveira Fialho, F.; Figueira, P.; Forveille,
   T.; Fridlund, M.; García, R. A.; Giommi, P.; Giuffrida, G.; Godolt,
   M.; Gomes da Silva, J.; Granzer, T.; Grenfell, J. L.; Grotsch-Noels,
   A.; Günther, E.; Haswell, C. A.; Hatzes, A. P.; Hébrard, G.; Hekker,
   S.; Helled, R.; Heng, K.; Jenkins, J. M.; Johansen, A.; Khodachenko,
   M. L.; Kislyakova, K. G.; Kley, W.; Kolb, U.; Krivova, N.; Kupka, F.;
   Lammer, H.; Lanza, A. F.; Lebreton, Y.; Magrin, D.; Marcos-Arenal,
   P.; Marrese, P. M.; Marques, J. P.; Martins, J.; Mathis, S.; Mathur,
   S.; Messina, S.; Miglio, A.; Montalban, J.; Montalto, M.; Monteiro,
   M. J. P. F. G.; Moradi, H.; Moravveji, E.; Mordasini, C.; Morel, T.;
   Mortier, A.; Nascimbeni, V.; Nelson, R. P.; Nielsen, M. B.; Noack,
   L.; Norton, A. J.; Ofir, A.; Oshagh, M.; Ouazzani, R. -M.; Pápics,
   P.; Parro, V. C.; Petit, P.; Plez, B.; Poretti, E.; Quirrenbach, A.;
   Ragazzoni, R.; Raimondo, G.; Rainer, M.; Reese, D. R.; Redmer, R.;
   Reffert, S.; Rojas-Ayala, B.; Roxburgh, I. W.; Salmon, S.; Santerne,
   A.; Schneider, J.; Schou, J.; Schuh, S.; Schunker, H.; Silva-Valio,
   A.; Silvotti, R.; Skillen, I.; Snellen, I.; Sohl, F.; Sousa, S. G.;
   Sozzetti, A.; Stello, D.; Strassmeier, K. G.; Švanda, M.; Szabó,
   Gy. M.; Tkachenko, A.; Valencia, D.; Van Grootel, V.; Vauclair,
   S. D.; Ventura, P.; Wagner, F. W.; Walton, N. A.; Weingrill, J.;
   Werner, S. C.; Wheatley, P. J.; Zwintz, K.
Bibcode: 2014ExA....38..249R
Altcode: 2014ExA...tmp...41R; 2013arXiv1310.0696R
  PLATO 2.0 has recently been selected for ESA's M3 launch opportunity
  (2022/24). Providing accurate key planet parameters (radius, mass,
  density and age) in statistical numbers, it addresses fundamental
  questions such as: How do planetary systems form and evolve? Are there
  other systems with planets like ours, including potentially habitable
  planets? The PLATO 2.0 instrument consists of 34 small aperture
  telescopes (32 with 25 s readout cadence and 2 with 2.5 s candence)
  providing a wide field-of-view (2232 deg <SUP>2</SUP>) and a large
  photometric magnitude range (4-16 mag). It focusses on bright (4-11
  mag) stars in wide fields to detect and characterize planets down to
  Earth-size by photometric transits, whose masses can then be determined
  by ground-based radial-velocity follow-up measurements. Asteroseismology
  will be performed for these bright stars to obtain highly accurate
  stellar parameters, including masses and ages. The combination of
  bright targets and asteroseismology results in high accuracy for
  the bulk planet parameters: 2 %, 4-10 % and 10 % for planet radii,
  masses and ages, respectively. The planned baseline observing strategy
  includes two long pointings (2-3 years) to detect and bulk characterize
  planets reaching into the habitable zone (HZ) of solar-like stars
  and an additional step-and-stare phase to cover in total about 50 %
  of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect
  and characterize hundreds of small planets, and thousands of planets
  in the Neptune to gas giant regime out to the HZ. It will therefore
  provide the first large-scale catalogue of bulk characterized planets
  with accurate radii, masses, mean densities and ages. This catalogue
  will include terrestrial planets at intermediate orbital distances,
  where surface temperatures are moderate. Coverage of this parameter
  range with statistical numbers of bulk characterized planets is unique
  to PLATO 2.0. The PLATO 2.0 catalogue allows us to e.g.: - complete
  our knowledge of planet diversity for low-mass objects, - correlate the
  planet mean density-orbital distance distribution with predictions from
  planet formation theories,- constrain the influence of planet migration
  and scattering on the architecture of multiple systems, and - specify
  how planet and system parameters change with host star characteristics,
  such as type, metallicity and age. The catalogue will allow us to study
  planets and planetary systems at different evolutionary phases. It
  will further provide a census for small, low-mass planets. This will
  serve to identify objects which retained their primordial hydrogen
  atmosphere and in general the typical characteristics of planets
  in such low-mass, low-density range. Planets detected by PLATO 2.0
  will orbit bright stars and many of them will be targets for future
  atmosphere spectroscopy exploring their atmosphere. Furthermore,
  the mission has the potential to detect exomoons, planetary rings,
  binary and Trojan planets. The planetary science possible with PLATO
  2.0 is complemented by its impact on stellar and galactic science via
  asteroseismology as well as light curves of all kinds of variable stars,
  together with observations of stellar clusters of different ages. This
  will allow us to improve stellar models and study stellar activity. A
  large number of well-known ages from red giant stars will probe the
  structure and evolution of our Galaxy. Asteroseismic ages of bright
  stars for different phases of stellar evolution allow calibrating
  stellar age-rotation relationships. Together with the results of ESA's
  Gaia mission, the results of PLATO 2.0 will provide a huge legacy to
  planetary, stellar and galactic science.

Title: Two planets around Kapteyn's star: a cold and a temperate
    super-Earth orbiting the nearest halo red dwarf.
Authors: Anglada-Escude, G.; Arriagada, P.; Tuomi, M.; Zechmeister,
   M.; Jenkins, J. S.; Ofir, A.; Dreizler, S.; Gerlach, E.; Marvin,
   C. J.; Reiners, A.; Jeffers, S. V.; Butler, R. P.; Vogt, S. S.; Amado,
   P. J.; Rodriguez-Lopez, C.; Berdinas, Z. M.; Morin, J.; Crane, J. D.;
   Shectman, S. A.; Thompson, I. B.; Diaz, M.; Rivera, E.; Sarmiento,
   L. F.; Jones, H. R. A.
Bibcode: 2014MNRAS.443L..89A
Altcode: 2014arXiv1406.0818A
  Exoplanets of a few Earth masses can be now detected around
  nearby low-mass stars using Doppler spectroscopy. In this Letter,
  we investigate the radial velocity variations of Kapteyn's star,
  which is both a sub-dwarf M-star and the nearest halo object to the
  Sun. The observations comprise archival and new HARPS (High Accuracy
  Radial velocity Planet Searcher), High Resolution Echelle Spectrometer
  (HIRES) and Planet Finder Spectrograph (PFS) Doppler measurements. Two
  Doppler signals are detected at periods of 48 and 120 d using likelihood
  periodograms and a Bayesian analysis of the data. Using the same
  techniques, the activity indices and archival All Sky Automated
  Survey (ASAS-3) photometry show evidence for low-level activity
  periodicities of the order of several hundred days. However, there
  are no significant correlations with the radial velocity variations on
  the same time-scales. The inclusion of planetary Keplerian signals in
  the model results in levels of correlated and excess white noise that
  are remarkably low compared to younger G, K and M dwarfs. We conclude
  that Kapteyn's star is most probably orbited by two super-Earth mass
  planets, one of which is orbiting in its circumstellar habitable zone,
  becoming the oldest potentially habitable planet known to date. The
  presence and long-term survival of a planetary system seem a remarkable
  feat given the peculiar origin and kinematic history of Kapteyn's
  star. The detection of super-Earth mass planets around halo stars
  provides important insights into planet-formation processes in the
  early days of the Milky Way.

Title: CARMENES ultra-stable cooling system: very promising results
Authors: Mirabet, E.; Carvas, P.; Lizon, J. -L.; Becerril, S.;
   Rodríguez, E.; Abril, M.; Cárdenas, M. C.; Morales, R.; Pérez,
   D.; Sánchez Carrasco, M. A.; Amado, P. J.; Seifert, W.; Quirrenbach,
   A.; Caballero, J. A.; Ribas, I.; Reiners, A.; Dreizler, S.
Bibcode: 2014SPIE.9151E..3YM
Altcode:
  CARMENES is a high resolution spectrograph to detect planets through the
  variation of radial velocity, destined for the Calar Alto Observatory
  in Almeria, Spain. The optical bench has a working temperature of 140K
  with a 24 hours stability of ±0,1K; goal ±0,01K. It is enclosed with
  a radiation shield actively cooled with thermalized nitrogen gas that
  flows through strategically positioned heat exchangers to remove its
  radiative load. The cooling system has an external preparation unit
  (N2GPU), which provides the nitrogen gas through actively vaporizing
  liquid nitrogen with heating resistances and a three stage circuit
  flow, each one controlled by an independent PID. Since CARMENES is
  still in the construction phase, a dedicated test facility has been
  built in order to simulate the instrument and correctly establish the
  N2GPU parameters. Furthermore, the test facility allows a wide range
  of configurations set-ups, which enables a full characterization of
  the N2GPU and the cooling system. The N2GPU has been designed to offer
  a wide temperature range of thermally stabilized nitrogen gas flow,
  which apart from CARMENES could also be used to provide ultra-high
  thermal stability in other cryogenic instruments. The present paper
  shows the testing of the cooling performance, the hardware used and
  the very promising results obtained.

Title: CARMENES instrument overview
Authors: Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Mundt,
   R.; Reiners, A.; Ribas, I.; Seifert, W.; Abril, M.; Aceituno, J.;
   Alonso-Floriano, F. J.; Ammler-von Eiff, M.; Antona Jiménez, R.;
   Anwand-Heerwart, H.; Azzaro, M.; Bauer, F.; Barrado, D.; Becerril, S.;
   Béjar, V. J. S.; Benítez, D.; Berdiñas, Z. M.; Cárdenas, M. C.;
   Casal, E.; Claret, A.; Colomé, J.; Cortés-Contreras, M.; Czesla,
   S.; Doellinger, M.; Dreizler, S.; Feiz, C.; Fernández, M.; Galadí,
   D.; Gálvez-Ortiz, M. C.; García-Piquer, A.; García-Vargas, M. L.;
   Garrido, R.; Gesa, L.; Gómez Galera, V.; González Álvarez, E.;
   González Hernández, J. I.; Grözinger, U.; Guàrdia, J.; Guenther,
   E. W.; de Guindos, E.; Gutiérrez-Soto, J.; Hagen, H. -J.; Hatzes,
   A. P.; Hauschildt, P. H.; Helmling, J.; Henning, T.; Hermann, D.;
   Hernández Castaño, L.; Herrero, E.; Hidalgo, D.; Holgado, G.;
   Huber, A.; Huber, K. F.; Jeffers, S.; Joergens, V.; de Juan, E.;
   Kehr, M.; Klein, R.; Kürster, M.; Lamert, A.; Lalitha, S.; Laun,
   W.; Lemke, U.; Lenzen, R.; López del Fresno, Mauro; López Martí,
   B.; López-Santiago, J.; Mall, U.; Mandel, H.; Martín, E. L.;
   Martín-Ruiz, S.; Martínez-Rodríguez, H.; Marvin, C. J.; Mathar,
   R. J.; Mirabet, E.; Montes, D.; Morales Muñoz, R.; Moya, A.; Naranjo,
   V.; Ofir, A.; Oreiro, R.; Pallé, E.; Panduro, J.; Passegger, V. -M.;
   Pérez-Calpena, A.; Pérez Medialdea, D.; Perger, M.; Pluto, M.;
   Ramón, A.; Rebolo, R.; Redondo, P.; Reffert, S.; Reinhardt, S.; Rhode,
   P.; Rix, H. -W.; Rodler, F.; Rodríguez, E.; Rodríguez-López, C.;
   Rodríguez-Pérez, E.; Rohloff, R. -R.; Rosich, A.; Sánchez-Blanco,
   E.; Sánchez Carrasco, M. A.; Sanz-Forcada, J.; Sarmiento, L. F.;
   Schäfer, S.; Schiller, J.; Schmidt, C.; Schmitt, J. H. M. M.; Solano,
   E.; Stahl, O.; Storz, C.; Stürmer, J.; Suárez, J. C.; Ulbrich,
   R. G.; Veredas, G.; Wagner, K.; Winkler, J.; Zapatero Osorio, M. R.;
   Zechmeister, M.; Abellán de Paco, F. J.; Anglada-Escudé, G.; del
   Burgo, C.; Klutsch, A.; Lizon, J. L.; López-Morales, M.; Morales,
   J. C.; Perryman, M. A. C.; Tulloch, S. M.; Xu, W.
Bibcode: 2014SPIE.9147E..1FQ
Altcode:
  This paper gives an overview of the CARMENES instrument and of the
  survey that will be carried out with it during the first years of
  operation. CARMENES (Calar Alto high-Resolution search for M dwarfs
  with Exoearths with Near-infrared and optical Echelle Spectrographs)
  is a next-generation radial-velocity instrument under construction
  for the 3.5m telescope at the Calar Alto Observatory by a consortium
  of eleven Spanish and German institutions. The scientific goal of the
  project is conducting a 600-night exoplanet survey targeting ~ 300 M
  dwarfs with the completed instrument. The CARMENES instrument consists
  of two separate echelle spectrographs covering the wavelength range
  from 0.55 to 1.7 μm at a spectral resolution of R = 82,000, fed by
  fibers from the Cassegrain focus of the telescope. The spectrographs
  are housed in vacuum tanks providing the temperature-stabilized
  environments necessary to enable a 1 m/s radial velocity precision
  employing a simultaneous calibration with an emission-line lamp
  or with a Fabry-Perot etalon. For mid-M to late-M spectral types,
  the wavelength range around 1.0 μm (Y band) is the most important
  wavelength region for radial velocity work. Therefore, the efficiency
  of CARMENES has been optimized in this range. The CARMENES instrument
  consists of two spectrographs, one equipped with a 4k x 4k pixel CCD
  for the range 0.55 - 1.05 μm, and one with two 2k x 2k pixel HgCdTe
  detectors for the range from 0.95 - 1.7μm. Each spectrograph will
  be coupled to the 3.5m telescope with two optical fibers, one for
  the target, and one for calibration light. The front end contains a
  dichroic beam splitter and an atmospheric dispersion corrector, to
  feed the light into the fibers leading to the spectrographs. Guiding
  is performed with a separate camera; on-axis as well as off-axis
  guiding modes are implemented. Fibers with octagonal cross-section
  are employed to ensure good stability of the output in the presence
  of residual guiding errors. The fibers are continually actuated to
  reduce modal noise. The spectrographs are mounted on benches inside
  vacuum tanks located in the coudé laboratory of the 3.5m dome. Each
  vacuum tank is equipped with a temperature stabilization system
  capable of keeping the temperature constant to within +/-0.01°C
  over 24 hours. The visible-light spectrograph will be operated near
  room temperature, while the near-IR spectrograph will be cooled to
  ~ 140 K. The CARMENES instrument passed its final design review in
  February 2013. The MAIV phase is currently ongoing. First tests at
  the telescope are scheduled for early 2015. Completion of the full
  instrument is planned for the fall of 2015. At least 600 useable
  nights have been allocated at the Calar Alto 3.5m Telescope for the
  CARMENES survey in the time frame until 2018. A data base of M stars
  (dubbed CARMENCITA) has been compiled from which the CARMENES sample
  can be selected. CARMENCITA contains information on all relevant
  properties of the potential targets. Dedicated imaging, photometric,
  and spectroscopic observations are underway to provide crucial data
  on these stars that are not available in the literature.

Title: VizieR Online Data Catalog: Kapteyn's star spectroscopic
    measurements (Anglada-Escude+ 2014)
Authors: Anglada-Escude, G.; Arriagada, P.; Tuomi, M.; Zechmeister,
   M.; Jenkins, J. S.; Ofir, A.; Dreizler, S.; Gerlach, E.; Marvin,
   C. J.; Reiners, A.; Jeffers, S. V.; Butler, R. P.; Vogt, S. S.; Amado,
   P. J.; Rodriguez-Lopez, C.; Berdinas, Z. M.; Morin, J.; Crane, J. D.;
   Shectman, S. A.; Thompson, I. B.; Diaz, M.; Rivera, E.; Sarmiento,
   L. F.; Jones, H. R. A.
Bibcode: 2014yCat..74439089A
Altcode:
  Time-series of spectroscopic measurements used in the paper. Median
  value and a perspective acceleration were subtracted to each RVs set
  (Ins. 1 is HARPS, 2 is HIRES, 3 is PFS). Measurements of the FWHM,
  BIS of the cross-correlation profiles and measurements of the S-index
  are provided for HARPS data only. Uncertainty in the FWHM is 2.5 times
  the uncertainty in BIS. Check (2012ApJS..200...15A), for more detailed
  definitions of the measurements and their uses. <P />(1 data file).

Title: TRIPP: Time Resolved Imaging Photometry Package
Authors: Geckeler, Ralf D.; Schuh, Sonja; Dreizler, Stefan; Deetjen,
   Jochen; Gleissner, Thomas; Risse, Patrick; Rauch, Thomas; Göhler,
   Eckart; Hügelmeyer, Simon; Husser, Tim-Oliver; Israel, Holger;
   Benlloch-Garcia, Sara; Pottschmidt, Katja; Wilms, Jörn
Bibcode: 2014ascl.soft05008G
Altcode:
  Written in IDL, TRIPP performs CCD time series reduction and
  analysis. It provides an on-line check of the incoming frames, performs
  relative aperture photometry and provides a set of time series tools,
  such as calculation of periodograms including false alarm probability
  determination, epoc folding, sinus fitting, and light curve simulations.

Title: Hot horizontal branch stars in NGC 288 - effects of diffusion
    and stratification on their atmospheric parameters
Authors: Moehler, S.; Dreizler, S.; LeBlanc, F.; Khalack, V.; Michaud,
   G.; Richer, J.; Sweigart, A. V.; Grundahl, F.
Bibcode: 2014A&A...565A.100M
Altcode: 2014arXiv1403.7397M
  Context. NGC 288 is a globular cluster with a well-developed blue
  horizontal branch (HB) covering the u-jump that indicates the onset of
  diffusion. It is therefore well suited to study the effects of diffusion
  in blue HB stars. <BR /> Aims: We compare observed abundances with
  predictions from stellar evolution models calculated with diffusion
  and from stratified atmospheric models. We verify the effect of
  using stratified model spectra to derive atmospheric parameters. In
  addition, we investigate the nature of the overluminous blue HB stars
  around the u-jump. <BR /> Methods: We defined a new photometric
  index sz from uvby measurements that is gravity-sensitive between
  8000 K and 12 000 K. Using medium-resolution spectra and Strömgren
  photometry, we determined atmospheric parameters (T<SUB>eff</SUB>,
  log g) and abundances for the blue HB stars. We used both homogeneous
  and stratified model spectra for our spectroscopic analyses. <BR />
  Results: The atmospheric parameters and masses of the hot HB stars in
  NGC 288 show a behaviour seen also in other clusters for temperatures
  between 9000 K and 14 000 K. Outside this temperature range, however,
  they instead follow the results found for such stars in ω Cen. The
  abundances derived from our observations are for most elements (except
  He and P) within the abundance range expected from evolutionary models
  that include the effects of atomic diffusion and assume a surface mixed
  mass of 10<SUP>-7</SUP> M<SUB>⊙</SUB>. The abundances predicted
  by stratified model atmospheres are generally significantly more
  extreme than observed, except for Mg. When effective temperatures,
  surface gravities, and masses are determined with stratified model
  spectra, the hotter stars agree better with canonical evolutionary
  predictions. <BR /> Conclusions: Our results show definite promise
  towards solving the long-standing problem of surface gravity and
  mass discrepancies for hot HB stars, but much work is still needed to
  arrive at a self-consistent solution. <P />Based on observations with
  the ESO Very Large Telescope at Paranal Observatory, Chile (proposal
  ID 71.D-0131).Tables 1 and 2 are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201322953/olm">http://www.aanda.org</A>The
  observed abundances plotted in Fig. 8 are
  only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/565/A100">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/565/A100</A>

Title: On the Current State of Ground-based Transmission Spectroscopy
    of Planet Atmospheres
Authors: Nortmann, Lisa; Dreizler, Stefan; Bean, Jacob
Bibcode: 2014IAUS..293..315N
Altcode:
  In response to the large number of exoplanet detections, the
  characterization of these planets has become a major focus of exoplanet
  science. Transiting planets are of particular interest as they allow
  us to investigate the transmission of their atmospheres. Our group uses
  ground-based facilities like the ESO/VLT to probe the atmosphere of hot
  Jupiters with the technique of spectrophotometry. In our preliminary
  results for the hot Jupiters WASP-17b and WASP-31b we find the reachable
  precision to be limited by instrumental systematic noise rather than
  photon noise. We discuss the source of the noise and suggest two
  approaches to correct it.

Title: Kepler-9 revisited 60% the mass with six times more data
Authors: Dreizler, Stefan; Ofir, Aviv
Bibcode: 2014arXiv1403.1372D
Altcode:
  Kepler-9 was the first case where transit timing variations have been
  used to confirm the planets in this system. Following predictions of
  dramatic TTVs - larger than a week - we re-analyse the system based
  on the full Kepler data set. We re-processed all available data for
  Kepler-9 removing short and long term trends, measured the times of
  mid-transit and used those for dynamical analysis of the system. The
  newly determined masses and radii of Kepler-9b and -9c change the nature
  of these planets relative to the one described in Holman et al. 2010
  (hereafter H10) with very low, but relatively well charcterised (to
  better than 7%), bulk densities of 0.18 and 0.14 g cm$^3$ (about 1/3
  of the H10 value). We constrain the masses (45.1 and 31.0 M$_\oplus$,
  for Kepler-9b and -9c respectively) from photometry alone, allowing
  us to see possible indications for an outer non-transiting planet in
  the radial velocity data. At $2R_\oplus$ Kepler-9d is determined to
  be larger than suggested before - suggesting that it is a low-mass
  low-density planet. The comparison between the H10 analysis and our
  new analysis suggests that small formal error in the TTV inversion
  may be misleading if the data does not cover a significant fraction
  of the interaction time scale.

Title: VizieR Online Data Catalog: NGC 288 hot horizontal branch
    stars abundances (Moehler+, 2014)
Authors: Moehler, S.; Dreizler, S.; Leblanc, F.; Khalack, V.; Michaud,
   G.; Richer, J.; Sweigart, A. V.; Grundahl, F.
Bibcode: 2014yCat..35650100M
Altcode: 2014yCat..35659100M
  Temperatures, surface gravities, and abundances for hot (Teff&gt;9000K)
  horizontal branch stars in NGC 288 as derived from medium-resolution
  FLAMES-GIRAFFE spectra (resolution about 0.7Å). Effective temperatures
  and surface gravities are derived from line profile fits. The abundances
  were derived via spectrum synthesis, using the presviously defined
  effective temperature and surface gravity. Errors are about Â±5%
  in Teff, Â±0.1 in logg, Â±0.2 (He), Â±0.28 (Mg), Â±0.34 (Si,
  P, Fe), Â±0.58 (Ti, Mn, Ni). 0.00 means that no abundance could be
  determined. <P />(2 data files).

Title: Planet formation from the ejecta of common envelopes
Authors: Schleicher, Dominik R. G.; Dreizler, Stefan
Bibcode: 2014A&A...563A..61S
Altcode: 2013arXiv1312.3479S
  Context. The close binary system NN Serpentis must have gone
  through a common envelope phase before the formation of its white
  dwarf. During this phase, a substantial amount of mass was lost from
  the envelope. The recently detected orbits of circumbinary planets are
  probably inconsistent with planet formation before the mass loss. <BR
  /> Aims: We explore whether new planets may have formed from the
  ejecta of the common envelope and derive the expected planetary mass
  as a function of radius. <BR /> Methods: We employed the Kashi &amp;
  Soker model to estimate the amount of mass that is retained during
  the ejection event and inferred the properties of the resulting disk
  from the conservation of mass and angular momentum. The resulting
  planetary masses were estimated from models with and without radiative
  feedback. <BR /> Results: We show that the observed planetary masses
  can be reproduced for appropriate model parameters. Photoheating
  can stabilize the disks in the interior, potentially explaining
  the observed planetary orbits on scales of a few AU. We compare
  the expected mass scale of planets for 11 additional systems with
  observational results and find hints of two populations, one consistent
  with planet formation from the ejecta of common envelopes and the
  other a separate population that may have formed earlier. <BR />
  Conclusions: The formation of the observed planets from the ejecta
  of common envelopes seems feasible. The model proposed here can be
  tested through refined observations of additional post-common envelope
  systems. While it appears observationally challenging to distinguish
  between the accretion on pre-existing planets and their growth from
  new fragments, it may be possible to further constrain the properties
  of the protoplanetary disk through additional observations of current
  planetary candidates and post-common envelope binary systems.

Title: Evidence for an oscillation of the magnetic axis of the white
    dwarf in the polar DP Leonis
Authors: Beuermann, K.; Dreizler, S.; Hessman, F. V.; Schwope, A. D.
Bibcode: 2014A&A...562A..63B
Altcode: 2014arXiv1401.1638B
  From 1979 to 2001, the magnetic axis of the white dwarf in the
  polar DP Leo slowly rotated by 50° in azimuth, possibly indicating
  a small asynchronism between the rotational and orbital periods of
  the magnetic white dwarf. Using the MONET/North telescope, we have
  obtained phase-resolved orbital light curves between 2009 and 2013,
  which show that this trend has not continued in recent years. Our data
  are consistent with the theoretically predicted oscillation of the
  magnetic axis of the white dwarf about an equilibrium orientation,
  which is defined by the competition between the accretion torque and
  the magnetostatic interaction of the primary and secondary star. Our
  data indicate an oscillation period of ~60 yr, an amplitude of about
  25°, and an equilibrium orientation leading the connecting line of
  the two stars by about 7°.

Title: An independent planet search in the Kepler dataset. II. An
    extremely low-density super-Earth mass planet around Kepler-87
Authors: Ofir, Aviv; Dreizler, Stefan; Zechmeister, Mathias; Husser,
   Tim-Oliver
Bibcode: 2014A&A...561A.103O
Altcode: 2013arXiv1310.2064O
  Context. The primary goal of the Kepler mission is the measurement of
  the frequency of Earth-like planets around Sun-like stars. However,
  the confirmation of the smallest of Kepler's candidates in long periods
  around FGK dwarfs is extremely difficult or even beyond the limit of
  current radial velocity technology. Transit timing variations (TTVs) may
  offer the possibility for these confirmations of near-resonant multiple
  systems by the mutual gravitational interaction of the planets. <BR />
  Aims: We previously detected the second planet candidate in the KOI
  1574 system. The two candidates have relatively long periods (about
  114 d and 191 d) and are in 5:3 resonance. We therefore searched for
  TTVs in this particularly promising system. <BR /> Methods: The full
  Kepler data was detrended with the proven SARS pipeline. The entire data
  allowed one to search for TTVs of the above signals, and to search for
  additional transit-like signals. <BR /> Results: We detected strong
  anti-correlated TTVs of the 114 d and 191 d signals, dynamically
  confirming them as members of the same system. Dynamical simulations
  reproducing the observed TTVs allowed us to also determine the masses
  of the planets. We found KOI 1574.01 (hereafter Kepler-87 b) to have
  a radius of 13.49 ± 0.55 R<SUB>⊕</SUB> and a mass of 324.2 ± 8.8
  M<SUB>⊕</SUB>, and KOI 1574.02 (Kepler-87 c) to have a radius of 6.14
  ± 0.29 R<SUB>⊕</SUB> and a mass of 6.4 ± 0.8 M<SUB>⊕</SUB>. Both
  planets have low densities of 0.729 and 0.152 g cm<SUP>-3</SUP>,
  respectively, which is non-trivial for such cold and old (7-8 Gyr)
  planets. Specifically, Kepler-87 c is the lowest-density planet
  in the super-Earth mass range. Both planets are thus particularly
  amenable to modeling and planetary structure studies, and also
  present an interesting case where ground-based photometric follow-up
  of Kepler planets is very desirable. Finally, we also detected two
  more short-period super-Earth sized (&lt;2 R<SUB>⊕</SUB>) planetary
  candidates in the system, making the relatively high multiplicity of
  this system notable against the general paucity of multiple systems
  in the presence of giant planets like Kepler-87 b.

Title: VizieR Online Data Catalog: WASP-15 and WASP-16 light curves
    (Southworth+, 2013)
Authors: Southworth, J.; Mancini, L.; Browne, P.; Burgdorf, M.; Calchi
   Novati, S.; Dominik, M.; Gerner, T.; Hinse, T. C.; Jorgensen, U. G.;
   Kains, N.; Ricci, D.; Schafer, S.; Schonebeck, F.; Tregloan-Reed, J.;
   Alsubai, K. A.; Bozza, V.; Chen, G.; Dodds, P.; Dreizler, S.; Fang,
   X. -S.; Finet, F.; Gu, S. -H.; Hardis, S.; Harpsoe, K.; Henning, T.;
   Hundertmark, M.; Jessen-Hansen, J.; Kerins, E.; Kjeldsen, H.; Liebig,
   C.; Lund, M. N.; Lundkvist, M.; Mathiasen, M.; Nikolov, N.; Penny,
   M. T.; Proft, S.; Rahvar, S.; Sahu, K.; Scarpetta, G.; Skottfelt,
   J.; Snodgrass, C.; Surdej, J.; Wertz, O.
Bibcode: 2013yCat..74341300S
Altcode:
  Nine light curves of six transits of the extrasolar planetary systems
  WASP-15 and WASP-16 are presented. The data were obtained using the
  Danish 1.5m telescope and DFOSC camera, and the ESO/MPI 2.2m telescope
  and GROND imager, with substantial telescope defocussing in order to
  improve the photometric precision of the observations. A Bessell R
  filter was used with DFOSC. The observations with GROND were obtained
  simultaneously through four filters: Sloan g, r, i and z. <P />(3
  data files).

Title: VizieR Online Data Catalog: New Kepler planetary candidates
    (Ofir+, 2013)
Authors: Ofir, A.; Dreizler, S.
Bibcode: 2013yCat..35550058O
Altcode: 2013yCat..35559058O
  We present first results of our efforts to re-analyze the Kepler
  photometric dataset, searching for planetary transits using an
  alternative processing pipeline to the one used by the Kepler mission
  The SARS pipeline was tried and tested extensively by processing all
  available CoRoT mission data. For this first paper of the series we
  used this pipeline to search for (additional) planetary transits only
  in a small subset of stars - the Kepler objects of interest (KOIs),
  which are already known to include at least one promising planet
  candidate. <P />(2 data files).

Title: The eclipsing post-common envelope binary CSS21055: a white
    dwarf with a probable brown-dwarf companion
Authors: Beuermann, K.; Dreizler, S.; Hessman, F. V.; Backhaus, U.;
   Boesch, A.; Husser, T. -O.; Nortmann, L.; Schmelev, A.; Springer, R.
Bibcode: 2013A&A...558A..96B
Altcode: 2013arXiv1312.5088B
  We report photometric observations of the eclipsing close binary
  CSS21055 (SDSS J141126+200911) that strongly suggest that the
  companion to the carbon-oxygen white dwarf is a brown dwarf with a
  mass between 0.030 and 0.074 M<SUB>⊙</SUB>. The measured orbital
  period is 121.73 min and the totality of the eclipse lasts 125 s. If
  confirmed, CSS21055 would be the first detached eclipsing WD+BD
  binary. Spectroscopy in the eclipse could provide information about
  the companion's evolutionary state and atmospheric structure. <P
  />Light curves are only available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/558/A96">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/558/A96</A>

Title: VizieR Online Data Catalog: Vi light curves of NGC6333
    variables (Arellano Ferro+, 2013)
Authors: Arellano Ferro, A.; Bramich, D. M.; Figuera Jaimes, R.;
   Giridhar, S.; Kains, N.; Kuppuswamy, K.; Jorgensen, U. G.; Alsubai,
   K. A.; Andersen, J. M.; Bozza, V.; Browne, P.; Calchi Novati,
   S.; Damerdji, Y.; Diehl, C.; Dominik, M.; Dreizler, S.; Elyiv, A.;
   Giannini, E.; Harpsoe, K.; Hessman, F. V.; Hinse, T. C.; Hundertmark,
   M.; Juncher, D.; Kerins, E.; Korhonen, H.; Liebig, C.; Mancini,
   L.; Mathiasen, M.; Penny, M. T.; Rabus, M.; Rahvar, S.; Ricci, D.;
   Scarpetta, G.; Skottfelt, J.; Snodgrass, C.; Southworth, J.; Surdej,
   J.; Tregloan-Reed, J.; Vilela, C.; Wertz, O.
Bibcode: 2013yCat..74341220A
Altcode:
  V and i time-series photometry for all confirmed variables in NGC
  6333. <P />(2 data files).

Title: A detailed census of variable stars in the globular cluster
    NGC 6333 (M9) from CCD differential photometry
Authors: Arellano Ferro, A.; Bramich, D. M.; Figuera Jaimes, R.;
   Giridhar, Sunetra; Kains, N.; Kuppuswamy, K.; Jørgensen, U. G.;
   Alsubai, K. A.; Andersen, J. M.; Bozza, V.; Browne, P.; Calchi Novati,
   S.; Damerdji, Y.; Diehl, C.; Dominik, M.; Dreizler, S.; Elyiv, A.;
   Giannini, E.; Harpsøe, K.; Hessman, F. V.; Hinse, T. C.; Hundertmark,
   M.; Juncher, D.; Kerins, E.; Korhonen, H.; Liebig, C.; Mancini,
   L.; Mathiasen, M.; Penny, M. T.; Rabus, M.; Rahvar, S.; Ricci, D.;
   Scarpetta, G.; Skottfelt, J.; Snodgrass, C.; Southworth, J.; Surdej,
   J.; Tregloan-Reed, J.; Vilela, C.; Wertz, O.; Mindstep Consortium
Bibcode: 2013MNRAS.434.1220A
Altcode: 2013MNRAS.tmp.1768A; 2013arXiv1306.3206A
  We report CCD V and I time series photometry of the globular cluster NGC
  6333 (M9). The technique of difference image analysis has been used,
  which enables photometric precision better than 0.05 mag for stars
  brighter than V ∼ 19.0 mag, even in the crowded central regions
  of the cluster. The high photometric precision has resulted in the
  discovery of two new RRc stars, three eclipsing binaries, seven
  long-term variables and one field RRab star behind the cluster. A
  detailed identification chart and equatorial coordinates are given for
  all the variable stars in the field of our images of the cluster. Our
  data together with the literature V-data obtained in 1994 and 1995
  allowed us to refine considerably the periods for all RR Lyrae
  stars. The nature of the new variables is discussed. We argue that
  variable V12 is a cluster member and an Anomalous Cepheid. Secular
  period variations, double-mode pulsations and/or the Blazhko-like
  modulations in some RRc variables are addressed. Through the light-curve
  Fourier decomposition of 12 RR Lyrae stars we have calculated a mean
  metallicity of [Fe/H]<SUB>ZW</SUB> = -1.70 ± 0.01(statistical) ±
  0.14(systematic) or [Fe/H]_{text{UVES}}=-1.67 ± 0.01(statistical)
  ± 0.19(systematic). Absolute magnitudes, radii and masses are also
  estimated for the RR Lyrae stars. A detailed search for SX Phe stars
  in the Blue Straggler region was conducted but none were discovered. If
  SX Phe exist in the cluster then their amplitudes must be smaller than
  the detection limit of our photometry. The colour-magnitude diagram
  has been corrected for heavy differential reddening using the detailed
  extinction map of the cluster of Alonso-García et al. This has allowed
  us to set the mean cluster distance from two independent estimates;
  from the RRab and RRc absolute magnitudes, we find 8.04 ± 0.19 and
  7.88 ± 0.30 kpc, respectively.

Title: VizieR Online Data Catalog: CSS21055 light curves (Beuermann+,
    2013)
Authors: Beuermann, K.; Dreizler, S.; Hessman, F. V.; Backhaus, U.;
   Boesch, A.; Husser, T. -O.; Nortmann, L.; Schmelev, A.; Springer, R.
Bibcode: 2013yCat..35580096B
Altcode: 2013yCat..35589096B
  Tables contain the numerical values for the light curves presented in
  Figs. 1a, 1b, and 1c. <P />(3 data files).

Title: High-precision photometry by telescope defocusing - V. WASP-15
    and WASP-16
Authors: Southworth, John; Mancini, L.; Browne, P.; Burgdorf,
   M.; Calchi Novati, S.; Dominik, M.; Gerner, T.; Hinse, T. C.;
   Jørgensen, U. G.; Kains, N.; Ricci, D.; Schäfer, S.; Schönebeck,
   F.; Tregloan-Reed, J.; Alsubai, K. A.; Bozza, V.; Chen, G.; Dodds,
   P.; Dreizler, S.; Fang, X. -S.; Finet, F.; Gu, S. -H.; Hardis, S.;
   Harpsøe, K.; Henning, Th.; Hundertmark, M.; Jessen-Hansen, J.;
   Kerins, E.; Kjeldsen, H.; Liebig, C.; Lund, M. N.; Lundkvist, M.;
   Mathiasen, M.; Nikolov, N.; Penny, M. T.; Proft, S.; Rahvar, S.; Sahu,
   K.; Scarpetta, G.; Skottfelt, J.; Snodgrass, C.; Surdej, J.; Wertz, O.
Bibcode: 2013MNRAS.434.1300S
Altcode: 2013MNRAS.tmp.1750S; 2013arXiv1306.3509S
  We present new photometric observations of WASP-15 and WASP-16,
  two transiting extrasolar planetary systems with measured orbital
  obliquities but without photometric follow-up since their discovery
  papers. Our new data for WASP-15 comprise observations of one transit
  simultaneously in four optical passbands using GROND on the MPG/European
  Southern Observatory (ESO) 2.2 m telescope, plus coverage of half
  a transit from DFOSC on the Danish 1.54 m telescope, both at ESO La
  Silla. For WASP-16 we present observations of four complete transits,
  all from the Danish telescope. We use these new data to refine the
  measured physical properties and orbital ephemerides of the two
  systems. Whilst our results are close to the originally determined
  values for WASP-15, we find that the star and planet in the WASP-16
  system are both larger and less massive than previously thought.

Title: VizieR Online Data Catalog: Transiting planetary system WASP-17
    (Southworth+, 2012)
Authors: Southworth, J.; Hinse, T. C.; Dominik, M.; Fang, X. -S.;
   Harpsoe, K.; Jorgensen, U. G.; Kerins, E.; Liebig, C.; Mancini, L.;
   Skottfelt, J.; Anderson, D. R.; Smalley, B.; Tregloan-Reed, J.; Wertz,
   O.; Alsubai, K. A.; Bozza, V.; Calchi Novati, S.; Dreizler, S.; Gu,
   S. -H.; Hundertmark, M.; Jessen-Hansen, J.; Kains, N.; Kjeldsen, H.;
   Lund, M. N.; Lundkvist, M.; Mathiasen, M.; Penny, M. T.; Rahvar, S.;
   Ricci, D.; Scarpetta, G.; Snodgrass, C.; Surdej, J.
Bibcode: 2013yCat..74261338S
Altcode:
  A light curve of four transits of the extrasolar planetary system
  WASP-17 is presented. The data were obtained using the Danish 1.5m
  telescope and DFOSC camera at ESO La Silla in 2012, with substantial
  telescope defocussing in order to improve the photometric precision
  of the observations. A Cousins R filter and exposure times of 120s
  were used. <P />(1 data file).

Title: High angular resolution imaging and infrared spectroscopy of
    CoRoT candidates
Authors: Guenther, E. W.; Fridlund, M.; Alonso, R.; Carpano, S.; Deeg,
   H. J.; Deleuil, M.; Dreizler, S.; Endl, M.; Gandolfi, D.; Gillon, M.;
   Guillot, T.; Jehin, E.; Léger, A.; Moutou, C.; Nortmann, L.; Rouan,
   D.; Samuel, B.; Schneider, J.; Tingley, B.
Bibcode: 2013A&A...556A..75G
Altcode: 2013arXiv1307.1660G
  Context. Studies of transiting extrasolar planets are of key
  importance for understanding the nature of planets outside our solar
  system because their masses, diameters, and bulk densities can be
  measured. An important part of transit-search programmes is the removal
  of false-positives. In the case of the CoRoT space mission, the majority
  of the false-positives are removed by a detailed analysis of the light
  curves and by seeing-limited imaging in- and out-of-transit. However,
  the critical question is how many of the candidates that passed all
  these tests are false-positives. Such false-positives can be caused
  by eclipsing binaries, which are either related or unrelated to the
  targets. <BR /> Aims: For our study we selected 25 CoRoT candidates
  that have already been screened against false-positives using detailed
  analysis of the light curves and seeing-limited imaging, which has
  transits that are between 0.7 and 0.05% deep. Our aim is to search
  for companion candidates that had not been recognized in previous
  observations. <BR /> Methods: We observed 20 candidates with the
  adaptive optics imager NaCo and 18 with the high-resolution infrared
  spectrograph CRIRES. <BR /> Results: We found previously unknown stars
  within 2'' of the targets in seven of the candidates. All of these are
  too faint and too close to the targets to have been previously detected
  with seeing-limited telescopes in the optical. Our study thus leads to
  the surprising results that if we remove all candidates excluded by the
  sophisticated analysis of the light-curve, as well as carrying out deep
  imaging with seeing-limited telescopes, still 28-35% of the remaining
  candidates are found to possess companions that are bright enough to be
  false-positives. <BR /> Conclusions: Given that the companion candidates
  cluster around the targets and that the J - K colours are consistent
  with physical companions, we conclude that the companion candidates
  are more likely to be physical companions rather than unrelated
  field stars. <P />Based on observations obtained at the European
  Southern Observatory at Paranal, Chile in programmes 282.C-5015A,
  282.C-5015B, 282.C-5015C, 285.C-5045A, and 285.C-5045B, 086.C-0235A,
  086.C-0235B, 088.C-0707A, 088.C-0707B, 090.C-0251A, 090.C-0251B, and
  091.C-203(A).Appendices A and B are available in electronic form at
  <A href="http://www.aanda.org">http://www.aanda.org</A>

Title: The quest for companions to post-common envelope
binaries. IV. The 2:1 mean-motion resonance of the planets orbiting
    NN Serpentis
Authors: Beuermann, K.; Dreizler, S.; Hessman, F. V.
Bibcode: 2013A&A...555A.133B
Altcode: 2013arXiv1305.6494B
  We present 69 new mid-eclipse times of the young post-common envelope
  binary (PCEB) <ASTROBJ>NN Ser</ASTROBJ>, which was previously suggested
  to possess two circumbinary planets. We have interpreted the observed
  eclipse-time variations in terms of the light-travel time effect
  caused by two planets, exhaustively covering the multi-dimensional
  parameter space by fits in the two binary and ten orbital parameters. We
  supplemented the fits by stability calculations for all models with an
  acceptable χ<SUP>2</SUP>. An island of secularly stable 2:1 resonant
  solutions exists, which coincides with the global χ<SUP>2</SUP>
  minimum. Our best-fit stable solution yields current orbital periods
  P<SUB>o</SUB> = 15.47 yr and P<SUB>i</SUB> = 7.65 yr and eccentricities
  e<SUB>o</SUB> = 0.14 and e<SUB>i</SUB> = 0.22 for the outer and inner
  planets, respectively. The companions qualify as giant planets, with
  masses of 7.0 M<SUB>Jup</SUB> and 1.7 M<SUB>Jup</SUB> for the case of
  orbits coplanar with that of the binary. The two-planet model that
  starts from the present system parameters has a lifetime greater
  than 10<SUP>8</SUP> yr, which significantly exceeds the age of NN
  Ser of 10<SUP>6</SUP> yr as a PCEB. The resonance is characterized by
  libration of the resonant variable Θ<SUB>1</SUB> and circulation of ,
  the difference between the arguments of periapse of the two planets. No
  stable nonresonant solutions were found, and the possibility of a
  5:2 resonance suggested previously by us is now excluded at the 99.3%
  confidence level. <P />Table 1 is available in electronic form at <A
  href="http://www.aanda.org">http://www.aanda.org</A>

Title: An independent planet search in the Kepler dataset. I. One
    hundred new candidates and revised Kepler objects of interest
Authors: Ofir, A.; Dreizler, S.
Bibcode: 2013A&A...555A..58O
Altcode: 2012arXiv1206.5347O
  <BR /> Aims: We present first results of our efforts to re-analyze the
  Kepler photometric dataset, searching for planetary transits using an
  alternative processing pipeline to the one used by the Kepler mission
  <BR /> Methods: The SARS pipeline was tried and tested extensively by
  processing all available CoRoT mission data. For this first paper of
  the series we used this pipeline to search for (additional) planetary
  transits only in a small subset of stars - the Kepler objects of
  interest (KOIs), which are already known to include at least one
  promising planet candidate. <BR /> Results: Although less than 1% of the
  Kepler dataset are KOIs we are able to significantly update the overall
  statistics of planetary multiplicity: we find 84 new transit signals
  on 64 systems on these light curves (LCs) only, nearly doubling the
  number of transit signals in these systems. Forty-one of the systems
  were singly-transiting systems that are now multiply-transiting. This
  significantly reduces the chances of false positive in them. Notable
  among the new discoveries are KOI 435 as a new six-candidate system
  (of which kind only Kepler-11 was known before), KOI 277 (which includes
  two candidates in a 6:7 period commensurability that has anti-correlated
  transit timing variations) - all but validating the system, KOIs 719,
  1574, and 1871 that have small planet candidates (1.15,2.05 and 1.71
  R<SUB>⊕</SUB>) in the habitable zone of their host star, and KOI 1843
  that exhibits the shortest period (4.25 h) and is among the smallest
  (0.63 R<SUB>⊕</SUB>) of all planet candidates. We are also able to
  reject 11 KOIs as eclipsing binaries based on photometry alone, update
  the ephemeris for five KOIs and otherwise discuss a number of other
  objects, which brings the total of new signals and revised KOIs in
  this study to more than one hundred. Interestingly, a large fraction,
  about ~1/3, of the newly detected candidates participate in period
  commensurabilities. Finally, we discuss the possible overestimation of
  parameter errors in the current list of KOIs and point out apparent
  problems in at least two of the parameters. <BR /> Conclusions: Our
  results strengthen previous analyses of the multi-transiting ensemble,
  and again highlight the great importance of this dataset. Nevertheless,
  we conclude that despite the phenomenal success of the Kepler mission,
  parallel analysis of the data by multiple teams is required to make
  full use of the data.

Title: A new extensive library of PHOENIX stellar atmospheres and
    synthetic spectra
Authors: Husser, T. -O.; Wende-von Berg, S.; Dreizler, S.; Homeier,
   D.; Reiners, A.; Barman, T.; Hauschildt, P. H.
Bibcode: 2013A&A...553A...6H
Altcode: 2013arXiv1303.5632H
  <BR /> Aims: We present a new library of high-resolution synthetic
  spectra based on the stellar atmosphere code PHOENIX that can be used
  for a wide range of applications of spectral analysis and stellar
  parameter synthesis. <BR /> Methods: The spherical mode of PHOENIX
  was used to create model atmospheres and to derive detailed synthetic
  stellar spectra from them. We present a new self-consistent way of
  describing micro-turbulence for our model atmospheres. <BR /> Results:
  The synthetic spectra cover the wavelength range from 500 Å to 5.5 μm
  with resolutions of R = 500 000 in the optical and near IR, R = 100 000
  in the IR and Δλ = 0.1 Å in the UV. The parameter space covers 2300
  K ≤ T<SUB>eff</SUB> ≤ 12 000 K, 0.0 ≤ log g ≤ +6.0, - 4.0 ≤
  [Fe/H] ≤ +1.0, and - 0.2 ≤ [α/Fe] ≤ +1.2. The library is a work
  in progress and we expect to extend it up to T<SUB>eff</SUB> = 25 000 K.

Title: CAFE: Calar Alto Fiber-fed Échelle spectrograph
Authors: Aceituno, J.; Sánchez, S. F.; Grupp, F.; Lillo, J.;
   Hernán-Obispo, M.; Benitez, D.; Montoya, L. M.; Thiele, U.; Pedraz,
   S.; Barrado, D.; Dreizler, S.; Bean, J.
Bibcode: 2013A&A...552A..31A
Altcode: 2013arXiv1301.2066A
  We present here CAFE, the Calar Alto Fiber-fed Échelle spectrograph,
  a new instrument built at the Centro Astronomico Hispano Alemán
  (CAHA). CAFE is a single-fiber, high-resolution (R ~ 70 000)
  spectrograph, covering the wavelength range between 3650-9800 Å. It was
  built on the basis of the common design for Échelle spectrographs. Its
  main aim is to measure radial velocities of stellar objects up to V ~
  13-14 mag with a precision as good as a few tens of m s<SUP>-1</SUP>. To
  achieve this goal the design was simplified at maximum, removing all
  possible movable components, the central wavelength is fixed, as is the
  wavelength coverage; there is no filter wheel, etc. Particular care
  was taken with the thermal and mechanical stability. The instrument
  is fully operational and publically accessible at the 2.2 m telescope
  of the Calar Alto Observatory. In this article we describe (i) the
  design, summarizing its manufacturing phase; (ii) characterize the main
  properties of the instrument; (iii) describe the reduction pipeline;
  and (iv) show the results from the first light and commissioning
  runs. The preliminar results indicate that the instrument fulfills the
  specifications and can achieve the planned goals. In particular, the
  results show that the instrument is more efficient than anticipated,
  reaching a signal-to-noise of ~20 for a stellar object as faint as V ~
  14.5 mag in ~2700 s integration time. The instrument is a wonderful
  machine for exoplanetary research (by studying large samples of
  possible systems cotaining massive planets), galactic dynamics (highly
  precise radial velocities in moving groups or stellar associations),
  or astrochemistry.

Title: A giant planet beyond the snow line in microlensing event
    OGLE-2011-BLG-0251
Authors: Kains, N.; Street, R. A.; Choi, J. -Y.; Han, C.; Udalski,
   A.; Almeida, L. A.; Jablonski, F.; Tristram, P. J.; Jørgensen,
   U. G.; Szymański, M. K.; Kubiak, M.; Pietrzyński, G.; Soszyński,
   I.; Poleski, R.; Kozłowski, S.; Pietrukowicz, P.; Ulaczyk, K.;
   Wyrzykowski, Ł.; Skowron, J.; Alsubai, K. A.; Bozza, V.; Browne, P.;
   Burgdorf, M. J.; Calchi Novati, S.; Dodds, P.; Dominik, M.; Dreizler,
   S.; Fang, X. -S.; Grundahl, F.; Gu, C. -H.; Hardis, S.; Harpsøe,
   K.; Hessman, F. V.; Hinse, T. C.; Hornstrup, A.; Hundertmark, M.;
   Jessen-Hansen, J.; Kerins, E.; Liebig, C.; Lund, M.; Lundkvist, M.;
   Mancini, L.; Mathiasen, M.; Penny, M. T.; Rahvar, S.; Ricci, D.;
   Sahu, K. C.; Scarpetta, G.; Skottfelt, J.; Snodgrass, C.; Southworth,
   J.; Surdej, J.; Tregloan-Reed, J.; Wambsganss, J.; Wertz, O.; Bajek,
   D.; Bramich, D. M.; Horne, K.; Ipatov, S.; Steele, I. A.; Tsapras,
   Y.; Abe, F.; Bennett, D. P.; Bond, I. A.; Botzler, C. S.; Chote,
   P.; Freeman, M.; Fukui, A.; Furusawa, K.; Itow, Y.; Ling, C. H.;
   Masuda, K.; Matsubara, Y.; Miyake, N.; Muraki, Y.; Ohnishi, K.;
   Rattenbury, N.; Saito, T.; Sullivan, D. J.; Sumi, T.; Suzuki, D.;
   Suzuki, K.; Sweatman, W. L.; Takino, S.; Wada, K.; Yock, P. C. M.;
   Allen, W.; Batista, V.; Chung, S. -J.; Christie, G.; DePoy, D. L.;
   Drummond, J.; Gaudi, B. S.; Gould, A.; Henderson, C.; Jung, Y. -K.;
   Koo, J. -R.; Lee, C. -U.; McCormick, J.; McGregor, D.; Muñoz, J. A.;
   Natusch, T.; Ngan, H.; Park, H.; Pogge, R. W.; Shin, I. -G.; Yee, J.;
   Albrow, M. D.; Bachelet, E.; Beaulieu, J. -P.; Brillant, S.; Caldwell,
   J. A. R.; Cassan, A.; Cole, A.; Corrales, E.; Coutures, Ch.; Dieters,
   S.; Dominis Prester, D.; Donatowicz, J.; Fouqué, P.; Greenhill, J.;
   Kane, S. R.; Kubas, D.; Marquette, J. -B.; Martin, R.; Meintjes, P.;
   Menzies, J.; Pollard, K. R.; Williams, A.; Wouters, D.; Zub, M.
Bibcode: 2013A&A...552A..70K
Altcode: 2013arXiv1303.1184K
  <BR /> Aims: We present the analysis of the gravitational microlensing
  event OGLE-2011-BLG-0251. This anomalous event was observed by several
  survey and follow-up collaborations conducting microlensing observations
  towards the Galactic bulge. <BR /> Methods: Based on detailed modelling
  of the observed light curve, we find that the lens is composed of
  two masses with a mass ratio q = 1.9 × 10<SUP>-3</SUP>. Thanks to
  our detection of higher-order effects on the light curve due to the
  Earth's orbital motion and the finite size of source, we are able
  to measure the mass and distance to the lens unambiguously. <BR />
  Results: We find that the lens is made up of a planet of mass 0.53 ±
  0.21 M<SUB>J</SUB> orbiting an M dwarf host star with a mass of 0.26 ±
  0.11 M<SUB>⊙</SUB>. The planetary system is located at a distance of
  2.57 ± 0.61 kpc towards the Galactic centre. The projected separation
  of the planet from its host star is d = 1.408 ± 0.019, in units of
  the Einstein radius, which corresponds to 2.72 ± 0.75 AU in physical
  units. We also identified a competitive model with similar planet and
  host star masses, but with a smaller orbital radius of 1.50 ± 0.50
  AU. The planet is therefore located beyond the snow line of its host
  star, which we estimate to be around ~1-1.5 AU.

Title: CARMENES: Blue planets orbiting red dwarfs
Authors: Quirrenbach, A.; Amado, P. J.; Caballero, J. A.; Mandel, H.;
   Mundt, R.; Reiners, A.; Ribas, I.; Sánchez Carrasco, M. A.; Seifert,
   W.; Azzaro, M.; Galadí, D.; Alonso-Floriano, F. J.; Dreizler, S.;
   Montes, D.; Rhode, P.; Stürmer, J.
Bibcode: 2013EPJWC..4705006Q
Altcode:
  The CARMENES (Calar Alto high-Resolution search for M dwarfs with
  Exo-earths with Near-infrared and optical Echelle Spectrographs)
  consortium, consisting of eleven Spanish and German institutions,
  has been established to conduct a radial-velocity survey of M dwarfs
  with the 3.5 m telescope at the Calar Alto Observatory. This survey
  will target ∼300 M stars, with emphasis on spectral types M4V
  and later. The CARMENES instrument is currently under construction;
  it consists of two independent échelle spectrographs covering the
  wavelength ranges 0.55 …1.05 μm and 0.95 …1.7 μm, respectively,
  at a spectral resolution of R = 82,000. The spectrographs are fed
  by fibers from the Cassegrain focus of the telescope; calibration is
  performed simultaneously with emission-line lamps. The optical benches
  of the spectrographs are housed in vacuum tanks and climatic chambers,
  which provide the temperature-stabilized environments necessary to
  enable a 1 m/s radial velocity precision.

Title: Flux and color variations of the doubly imaged quasar UM673
Authors: Ricci, D.; Elyiv, A.; Finet, F.; Wertz, O.; Alsubai, K.;
   Anguita, T.; Bozza, V.; Browne, P.; Burgdorf, M.; Calchi Novati,
   S.; Dodds, P.; Dominik, M.; Dreizler, S.; Gerner, T.; Glitrup, M.;
   Grundahl, F.; Hardis, S.; Harpsøe, K.; Hinse, T. C.; Hornstrup, A.;
   Hundertmark, M.; Jørgensen, U. G.; Kains, N.; Kerins, E.; Liebig, C.;
   Maier, G.; Mancini, L.; Masi, G.; Mathiasen, M.; Penny, M.; Proft,
   S.; Rahvar, S.; Scarpetta, G.; Sahu, K.; Schäfer, S.; Schönebeck,
   F.; Schmidt, R.; Skottfelt, J.; Snodgrass, C.; Southworth, J.; Thöne,
   C. C.; Wambsganss, J.; Zimmer, F.; Zub, M.; Surdej, J.
Bibcode: 2013A&A...551A.104R
Altcode: 2013arXiv1302.0766R
  <BR /> Aims: With the aim of characterizing the flux and color
  variations of the multiple components of the gravitationally lensed
  quasar <ASTROBJ>UM673</ASTROBJ> as a function of time, we have
  performed multiepoch and multiband photometric observations with the
  Danish telescope at the La Silla Observatory. <BR /> Methods: The
  observations were carried out in the VRi spectral bands during four
  seasons (2008-2011). We reduced the data using the point spread function
  photometric technique as well as aperture photometry. <BR /> Results:
  Our results show for the brightest lensed component some significant
  decrease in flux between the first two seasons (+ 0.09/+ 0.11/+ 0.05
  mag) and a subsequent increase during the following ones (- 0.11/-
  0.11/- 0.10 mag) in the V/R/i spectral bands, respectively. Comparing
  our results with previous studies, we find smaller color variations
  between these seasons as compared with previous ones. We also separate
  the contribution of the lensing galaxy from that of the fainter and
  close lensed component. <P />Based on data collected by MiNDSTEp with
  the Danish 1.54 m telescope at the ESO La Silla ObservatoryLight curves
  are only available in electronic from at the CDS via anonymous ftp
  to <A href="http://cdsarc.u-strasbg.fr">cdsarc.u-strasbg.fr</A>
  (<A href="http://130.79.128.5">130.79.128.5</A>) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/551/A104">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/551/A104</A>

Title: VizieR Online Data Catalog: Lensed QSO UM673/Q0142-100 VRi
    light curves (Ricci+, 2013)
Authors: Ricci, D.; Elyiv, A.; Finet, F.; Wertz, O.; Alsubai, K.;
   Anguita, T.; Bozza, V.; Browne, P.; Burgdorf, M.; Calchi Novati,
   S.; Dodds, P.; Dominik, M.; Dreizler, S.; Gerner, T.; Glitrup, M.;
   Grundahl, F.; Hardis, S.; Harpsoe, K.; Hinse, T. C.; Hornstrup, A.;
   Hundertmark, M.; Jorgensen, U. G.; Kains, N.; Kerins, E.; Liebig, C.;
   Maier, G.; Mancini, L.; Masi, G.; Mathiasen, M.; Penny, M.; Proft,
   S.; Rahvar, S.; Scarpetta, G.; Sahu, K.; Schaefer, S.; Schoenebeck,
   F.; Schmidt, R.; Skottfelt, J.; Snodgrass, C.; Southworth, J.; Thoene,
   C. C.; Wambsganss, J.; Zimmer, F.; Zub, M.; Surdej, J.
Bibcode: 2013yCat..35510104R
Altcode: 2013yCat..35519104R
  The Table contains the light curves, in the V, R, and i bands, of the
  two lensed components of the quasar UM673. The Table also contains
  the light curve of the "B+G" component, obtained by superposing the
  flux of the fainter B component and the flux of the lens galaxy. <P
  />(1 data file).

Title: MOA-2010-BLG-073L: An M-dwarf with a Substellar Companion at
    the Planet/Brown Dwarf Boundary
Authors: Street, R. A.; Choi, J. -Y.; Tsapras, Y.; Han, C.; Furusawa,
   K.; Hundertmark, M.; Gould, A.; Sumi, T.; Bond, I. A.; Wouters,
   D.; Zellem, R.; Udalski, A.; RoboNet Collaboration; Snodgrass, C.;
   Horne, K.; Dominik, M.; Browne, P.; Kains, N.; Bramich, D. M.; Bajek,
   D.; Steele, I. A.; Ipatov, S.; MOA Collaboration; Abe, F.; Bennett,
   D. P.; Botzler, C. S.; Chote, P.; Freeman, M.; Fukui, A.; Harris, P.;
   Itow, Y.; Ling, C. H.; Masuda, K.; Matsubara, Y.; Miyake, N.; Muraki,
   Y.; Nagayama, T.; Nishimaya, S.; Ohnishi, K.; Rattenbury, N.; Saito,
   To.; Sullivan, D. J.; Suzuki, D.; Sweatman, W. L.; Tristram, P. J.;
   Wada, K.; Yock, P. C. M.; OGLE Collaboration; Szymański, M. K.;
   Kubiak, M.; Pietrzyński, G.; Soszyński, I.; Poleski, R.; Ulaczyk,
   K.; Wyrzykowski, Ł.; μFUN Collaboration; Yee, J.; Dong, S.; Shin,
   I. -G.; Lee, C. -U.; Skowron, J.; De Almeida, L. Andrade; DePoy,
   D. L.; Gaudi, B. S.; Hung, L. -W.; Jablonski, F.; Kaspi, S.; Klein,
   N.; Hwang, K. -H.; Koo, J. -R.; Maoz, D.; Muñoz, J. A.; Pogge, R. W.;
   Polishhook, D.; Shporer, A.; McCormick, J.; Christie, G.; Natusch, T.;
   Allen, B.; Drummond, J.; Moorhouse, D.; Thornley, G.; Knowler, M.;
   Bos, M.; Bolt, G.; PLANET Collaboration; Beaulieu, J. -P.; Albrow,
   M. D.; Batista, V.; Brillant, S.; Caldwell, J. A. R.; Cassan, A.;
   Cole, A.; Corrales, E.; Coutures, Ch.; Dieters, S.; Dominis Prester,
   D.; Donatowicz, J.; Fouqué, P.; Bachelet, E.; Greenhill, J.; Kane,
   S. R.; Kubas, D.; Marquette, J. -B.; Martin, R.; Menzies, J.; Pollard,
   K. R.; Sahu, K. C.; Wambsganss, J.; Williams, A.; Zub, M.; MiNDSTEp;
   Alsubai, K. A.; Bozza, V.; Burgdorf, M. J.; Calchi Novati, S.; Dodds,
   P.; Dreizler, S.; Finet, F.; Gerner, T.; Hardis, S.; Harpsøe, K.;
   Hessman, F.; Hinse, T. C.; Jørgensen, U. G.; Kerins, E.; Liebig,
   C.; Mancini, L.; Mathiasen, M.; Penny, M. T.; Proft, S.; Rahvar, S.;
   Ricci, D.; Scarpetta, G.; Schäfer, S.; Schönebeck, F.; Southworth,
   J.; Surdej, J.
Bibcode: 2013ApJ...763...67S
Altcode: 2012arXiv1211.3782S
  We present an analysis of the anomalous microlensing event,
  MOA-2010-BLG-073, announced by the Microlensing Observations in
  Astrophysics survey on 2010 March 18. This event was remarkable
  because the source was previously known to be photometrically
  variable. Analyzing the pre-event source light curve, we demonstrate
  that it is an irregular variable over timescales &gt;200 days. Its
  dereddened color, (V - I)<SUB> S, 0</SUB>, is 1.221 ± 0.051 mag,
  and from our lens model we derive a source radius of 14.7 ± 1.3 R
  <SUB>⊙</SUB>, suggesting that it is a red giant star. We initially
  explored a number of purely microlensing models for the event but
  found a residual gradient in the data taken prior to and after the
  event. This is likely to be due to the variability of the source rather
  than part of the lensing event, so we incorporated a slope parameter
  in our model in order to derive the true parameters of the lensing
  system. We find that the lensing system has a mass ratio of q = 0.0654
  ± 0.0006. The Einstein crossing time of the event, t <SUB>E</SUB> =
  44.3 ± 0.1 days, was sufficiently long that the light curve exhibited
  parallax effects. In addition, the source trajectory relative to the
  large caustic structure allowed the orbital motion of the lens system
  to be detected. Combining the parallax with the Einstein radius, we
  were able to derive the distance to the lens, D<SUB>L</SUB> = 2.8 ±
  0.4 kpc, and the masses of the lensing objects. The primary of the lens
  is an M-dwarf with M <SUB> L, 1</SUB> = 0.16 ± 0.03 M <SUB>⊙</SUB>,
  while the companion has M <SUB> L, 2</SUB> = 11.0 ± 2.0 M <SUB>J</SUB>,
  putting it in the boundary zone between planets and brown dwarfs.

Title: Microlensing Binaries with Candidate Brown Dwarf Companions
Authors: Shin, I. -G.; Han, C.; Gould, A.; Udalski, A.; Sumi, T.;
   Dominik, M.; Beaulieu, J. -P.; Tsapras, Y.; Bozza, V.; Szymański,
   M. K.; Kubiak, M.; Soszyński, I.; Pietrzyński, G.; Poleski,
   R.; Ulaczyk, K.; Pietrukowicz, P.; Kozłowski, S.; Skowron, J.;
   Wyrzykowski, Ł.; OGLE Collaboration; Abe, F.; Bennett, D. P.;
   Bond, I. A.; Botzler, C. S.; Freeman, M.; Fukui, A.; Furusawa, K.;
   Hayashi, F.; Hearnshaw, J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.;
   Kilmartin, P. M.; Kobara, S.; Korpela, A.; Lin, W.; Ling, C. H.;
   Makita, S.; Masuda, K.; Matsubara, Y.; Miyake, N.; Muraki, Y.;
   Nagaya, M.; Nishimoto, K.; Ohnishi, K.; Okumura, T.; Omori, K.;
   Perrott, Y. C.; Rattenbury, N.; Saito, To.; Skuljan, L.; Sullivan,
   D. J.; Suzuki, D.; Sweatman, W. L.; Tristram, P. J.; Wada, K.; Yock,
   P. C. M.; MOA Collaboration; Christie, G. W.; Depoy, D. L.; Dong,
   S.; Gal-Yam, A.; Gaudi, B. S.; Hung, L. -W.; Janczak, J.; Kaspi, S.;
   Maoz, D.; McCormick, J.; McGregor, D.; Moorhouse, D.; Muñoz, J. A.;
   Natusch, T.; Nelson, C.; Pogge, R. W.; Tan, T. -G.; Polishook, D.;
   Shvartzvald, Y.; Shporer, A.; Thornley, G.; Malamud, U.; Yee, J. C.;
   Choi, J. -Y.; Jung, Y. -K.; Park, H.; Lee, C. -U.; Park, B. -G.; Koo,
   J. -R.; μFUN Collaboration; Bajek, D.; Bramich, D. M.; Browne, P.;
   Horne, K.; Ipatov, S.; Snodgrass, C.; Steele, I.; Street, R.; Alsubai,
   K. A.; Burgdorf, M. J.; Calchi Novati, S.; Dodds, P.; Dreizler, S.;
   Fang, X. -S.; Grundahl, F.; Gu, C. -H.; Hardis, S.; Harpsøe, K.;
   Hinse, T. C.; Hundertmark, M.; Jessen-Hansen, J.; Jørgensen, U. G.;
   Kains, N.; Kerins, E.; Liebig, C.; Lund, M.; Lundkvist, M.; Mancini,
   L.; Mathiasen, M.; Hornstrup, A.; Penny, M. T.; Proft, S.; Rahvar, S.;
   Ricci, D.; Scarpetta, G.; Skottfelt, J.; Southworth, J.; Surdej, J.;
   Tregloan-Reed, J.; Wertz, O.; Zimmer, F.; Albrow, M. D.; Batista, V.;
   Brillant, S.; Caldwell, J. A. R.; Calitz, J. J.; Cassan, A.; Cole,
   A.; Cook, K. H.; Corrales, E.; Coutures, Ch.; Dieters, S.; Dominis
   Prester, D.; Donatowicz, J.; Fouqué, P.; Greenhill, J.; Hill, K.;
   Hoffman, M.; Kane, S. R.; Kubas, D.; Marquette, J. -B.; Martin, R.;
   Meintjes, P.; Menzies, J.; Pollard, K. R.; Sahu, K. C.; Wambsganss,
   J.; Williams, A.; Vinter, C.; Zub, M.
Bibcode: 2012ApJ...760..116S
Altcode: 2012arXiv1208.2323S
  Brown dwarfs are important objects because they may provide a missing
  link between stars and planets, two populations that have dramatically
  different formation histories. In this paper, we present the candidate
  binaries with brown dwarf companions that are found by analyzing
  binary microlensing events discovered during the 2004-2011 observation
  seasons. Based on the low mass ratio criterion of q &lt; 0.2, we
  found seven candidate events: OGLE-2004-BLG-035, OGLE-2004-BLG-039,
  OGLE-2007-BLG-006, OGLE-2007-BLG-399/MOA-2007-BLG-334,
  MOA-2011-BLG-104/OGLE-2011-BLG-0172, MOA-2011-BLG-149, and
  MOA-201-BLG-278/OGLE-2011-BLG-012N. Among them, we are able to confirm
  that the companions of the lenses of MOA-2011-BLG-104/OGLE-2011-BLG-0172
  and MOA-2011-BLG-149 are brown dwarfs by determining the mass of the
  lens based on the simultaneous measurement of the Einstein radius and
  the lens parallax. The measured masses of the brown dwarf companions are
  0.02 ± 0.01 M <SUB>⊙</SUB> and 0.019 ± 0.002 M <SUB>⊙</SUB> for
  MOA-2011-BLG-104/OGLE-2011-BLG-0172 and MOA-2011-BLG-149, respectively,
  and both companions are orbiting low-mass M dwarf host stars. More
  microlensing brown dwarfs are expected to be detected as the number
  of lensing events with well-covered light curves increases with
  new-generation searches.

Title: TMAP: Tübingen NLTE Model-Atmosphere Package
Authors: Werner, Klaus; Dreizler, Stefan; Rauch, Thomas
Bibcode: 2012ascl.soft12015W
Altcode:
  The Tübingen NLTE Model-Atmosphere Package (TMAP) is a tool to
  calculate stellar atmospheres in spherical or plane-parallel geometry
  in hydrostatic and radiative equilibrium allowing departures from local
  thermodynamic equilibrium (LTE) for the population of atomic levels. It
  is based on the Accelerated Lambda Iteration (ALI) method and is able
  to account for line blanketing by metals. All elements from hydrogen
  to nickel may be included in the calculation with model atoms which
  are tailored for the aims of the user.

Title: A brown dwarf orbiting an M-dwarf: MOA 2009-BLG-411L
Authors: Bachelet, E.; Fouqué, P.; Han, C.; Gould, A.; Albrow,
   M. D.; Beaulieu, J. -P.; Bertin, E.; Bond, I. A.; Christie, G. W.;
   Heyrovský, D.; Horne, K.; Jørgensen, U. G.; Maoz, D.; Mathiasen,
   M.; Matsunaga, N.; McCormick, J.; Menzies, J.; Nataf, D.; Natusch, T.;
   Oi, N.; Renon, N.; Tsapras, Y.; Udalski, A.; Yee, J. C.; Batista, V.;
   Bennett, D. P.; Brillant, S.; Caldwell, J. A. R.; Cassan, A.; Cole,
   A.; Cook, K. H.; Coutures, C.; Dieters, S.; Dominik, M.; Dominis
   Prester, D.; Donatowicz, J.; Greenhill, J.; Kains, N.; Kane, S. R.;
   Marquette, J. -B.; Martin, R.; Pollard, K. R.; Sahu, K. C.; Street,
   R. A.; Wambsganss, J.; Williams, A.; Zub, M.; PLANET Collaboration;
   Bos, M.; Dong, Subo; Drummond, J.; Gaudi, B. S.; Graff, D.; Janczak,
   J.; Kaspi, S.; Kozłowski, S.; Lee, C. -U.; Monard, L. A. G.; Muñoz,
   J. A.; Park, B. -G.; Pogge, R. W.; Polishook, D.; Shporer, A.; Fun
   Collaboration; Abe, F.; Botzler, C. S.; Fukui, A.; Furusawa, K.;
   Hearnshaw, J. B.; Itow, Y.; Korpela, A. V.; Ling, C. H.; Masuda,
   K.; Matsubara, Y.; Miyake, N.; Muraki, Y.; Ohnishi, K.; Rattenbury,
   N. J.; Saito, To.; Sullivan, D.; Sumi, T.; Suzuki, D.; Sweatman,
   W. L.; Tristram, P. J.; Wada, K.; MOA Collaboration; Allan, A.; Bode,
   M. F.; Bramich, D. M.; Clay, N.; Fraser, S. N.; Hawkins, E.; Kerins,
   E.; Lister, T. A.; Mottram, C. J.; Saunders, E. S.; Snodgrass, C.;
   Steele, I. A.; Wheatley, P. J.; ROBONET-II Collaboration; Bozza, V.;
   Browne, P.; Burgdorf, M. J.; Calchi Novati, S.; Dreizler, S.; Finet,
   F.; Glitrup, M.; Grundahl, F.; HarpsøE, K.; Hessman, F. V.; Hinse,
   T. C.; Hundertmark, M.; Liebig, C.; Maier, G.; Mancini, L.; Rahvar,
   S.; Ricci, D.; Scarpetta, G.; Skottfelt, J.; Southworth, J.; Surdej,
   J.; Zimmer, F.; Mindstep Consortium
Bibcode: 2012A&A...547A..55B
Altcode:
  Context. Caustic crossing is the clearest signature of binary lenses
  in microlensing. In the present context, this signature is diluted
  by the large source star but a detailed analysis has allowed the
  companion signal to be extracted. <BR /> Aims: MOA 2009-BLG-411
  was detected on August 5, 2009 by the MOA-Collaboration. Alerted as
  a high-magnification event, it was sensitive to planets. Suspected
  anomalies in the light curve were not confirmed by a real-time model,
  but further analysis revealed small deviations from a single lens
  extended source fit. <BR /> Methods: Thanks to observations by all
  the collaborations, this event was well monitored. We first decided to
  characterize the source star properties by using a more refined method
  than the classical one: we measure the interstellar absorption along the
  line of sight in five different passbands (VIJHK). Secondly, we model
  the lightcurve by using the standard technique: make (s,q,α) grids
  to look for local minima and refine the results by using a downhill
  method (Markov chain Monte Carlo). Finally, we use a Galactic model
  to estimate the physical properties of the lens components. <BR />
  Results: We find that the source star is a giant G star with radius
  9 R<SUB>⊙</SUB>. The grid search gives two local minima, which
  correspond to the theoretical degeneracy s ≡ s<SUP>-1</SUP>. We
  find that the lens is composed of a brown dwarf secondary of mass
  M<SUB>S</SUB> = 0.05 M<SUB>⊙</SUB> orbiting a primary M-star
  of mass M<SUB>P</SUB> = 0.18 M<SUB>⊙</SUB>. We also reveal a new
  mass-ratio degeneracy for the central caustics of close binaries. <BR />
  Conclusions: As far as we are aware, this is the first detection using
  the microlensing technique of a binary system in our Galaxy composed of
  an M-star and a brown dwarf. <P />Appendix is available in electronic
  form at <A href="http://www.aanda.org">http://www.aanda.org</A>

Title: High-precision photometry by telescope defocusing -
    IV. Confirmation of the huge radius of WASP-17 b
Authors: Southworth, John; Hinse, T. C.; Dominik, M.; Fang, X. -S.;
   Harpsøe, K.; Jørgensen, U. G.; Kerins, E.; Liebig, C.; Mancini, L.;
   Skottfelt, J.; Anderson, D. R.; Smalley, B.; Tregloan-Reed, J.; Wertz,
   O.; Alsubai, K. A.; Bozza, V.; Calchi Novati, S.; Dreizler, S.; Gu,
   S. -H.; Hundertmark, M.; Jessen-Hansen, J.; Kains, N.; Kjeldsen, H.;
   Lund, M. N.; Lundkvist, M.; Mathiasen, M.; Penny, M. T.; Rahvar, S.;
   Ricci, D.; Scarpetta, G.; Snodgrass, C.; Surdej, J.
Bibcode: 2012MNRAS.426.1338S
Altcode: 2012arXiv1207.5797S
  We present photometric observations of four transits in the WASP-17
  planetary system, obtained using telescope defocusing techniques and
  with scatters reaching 0.5 mmag per point. Our revised orbital period is
  4.0 ± 0.6 s longer than previous measurements, a difference of 6.6σ,
  and does not support the published detections of orbital eccentricity
  in this system. We model the light curves using the JKTEBOP code and
  calculate the physical properties of the system by recourse to five
  sets of theoretical stellar model predictions. The resulting planetary
  radius, R<SUB>b</SUB> = 1.932 ± 0.052 ± 0.010 R<SUB>Jup</SUB>
  (statistical and systematic errors, respectively), provides confirmation
  that WASP-17 b is the largest planet currently known. All 14 planets
  with radii measured to be greater than 1.6 R<SUB>Jup</SUB> are found
  around comparatively hot (T<SUB>eff</SUB> &gt; 5900 K) and massive
  (M<SUB>A</SUB> &gt; 1.15 M<SUB>⊙</SUB>) stars. Chromospheric activity
  indicators are available for eight of these stars, and all imply a low
  activity level. The planets have small or zero orbital eccentricities,
  so tidal effects struggle to explain their large radii. The observed
  dearth of large planets around small stars may be natural but could
  also be due to observational biases against deep transits, if these are
  mistakenly labelled as false positives and so not followed up. Based
  on data collected by MiNDSTEp with the Danish 1.54-m telescope at the
  ESO La Silla Observatory.Royal Society University Research Fellow.

Title: A New Type of Ambiguity in the Planet and Binary
    Interpretations of Central Perturbations of High-magnification
    Gravitational Microlensing Events
Authors: Choi, J. -Y.; Shin, I. -G.; Han, C.; Udalski, A.; Sumi, T.;
   Gould, A.; Bozza, V.; Dominik, M.; Fouqué, P.; Horne, K.; Szymański,
   M. K.; Kubiak, M.; Soszyński, I.; Pietrzyński, G.; Poleski,
   R.; Ulaczyk, K.; Pietrukowicz, P.; Kozłowski, S.; Skowron, J.;
   Wyrzykowski, Ł.; OGLE Collaboration; Abe, F.; Bennett, D. P.; Bond,
   I. A.; Botzler, C. S.; Chote, P.; Freeman, M.; Fukui, A.; Furusawa,
   K.; Itow, Y.; Kobara, S.; Ling, C. H.; Masuda, K.; Matsubara, Y.;
   Miyake, N.; Muraki, Y.; Ohmori, K.; Ohnishi, K.; Rattenbury, N. J.;
   Saito, To.; Sullivan, D. J.; Suzuki, D.; Suzuki, K.; Sweatman,
   W. L.; Takino, S.; Tristram, P. J.; Wada, K.; Yock, P. C. M.;
   MOA Collaboration; Bramich, D. M.; Snodgrass, C.; Steele, I. A.;
   Street, R. A.; Tsapras, Y.; RoboNet Collaboration; Alsubai, K. A.;
   Browne, P.; Burgdorf, M. J.; Calchi Novati, S.; Dodds, P.; Dreizler,
   S.; Fang, X. -S.; Grundahl, F.; Gu, C. -H.; Hardis, S.; Harpsøe,
   K.; Hinse, T. C.; Hornstrup, A.; Hundertmark, M.; Jessen-Hansen,
   J.; Jørgensen, U. G.; Kains, N.; Kerins, E.; Liebig, C.; Lund, M.;
   Lunkkvist, M.; Mancini, L.; Mathiasen, M.; Penny, M. T.; Rahvar, S.;
   Ricci, D.; Scarpetta, G.; Skottfelt, J.; Southworth, J.; Surdej, J.;
   Tregloan-Reed, J.; Wambsganss, J.; Wertz, O.; MiNDSTEp Consortium;
   Almeida, L. A.; Batista, V.; Christie, G.; DePoy, D. L.; Dong, Subo;
   Gaudi, B. S.; Henderson, C.; Jablonski, F.; Lee, C. -U.; McCormick,
   J.; McGregor, D.; Moorhouse, D.; Natusch, T.; Ngan, H.; Pogge, R. W.;
   Tan, T. -G.; Thornley, G.; Yee, J. C.; μFUN Collaboration; Albrow,
   M. D.; Bachelet, E.; Beaulieu, J. -P.; Brillant, S.; Cassan, A.; Cole,
   A. A.; Corrales, E.; Coutures, C.; Dieters, S.; Dominis Prester, D.;
   Donatowicz, J.; Greenhill, J.; Kubas, D.; Marquette, J. -B.; Menzies,
   J. W.; Sahu, K. C.; Zub, M.; PLANET Collaboration
Bibcode: 2012ApJ...756...48C
Altcode: 2012arXiv1204.4789C
  High-magnification microlensing events provide an important channel to
  detect planets. Perturbations near the peak of a high-magnification
  event can be produced either by a planet or a binary companion. It
  is known that central perturbations induced by both types of
  companions can be generally distinguished due to the essentially
  different magnification pattern around caustics. In this paper, we
  present a case of central perturbations for which it is difficult to
  distinguish the planetary and binary interpretations. The peak of a
  lensing light curve affected by this perturbation appears to be blunt
  and flat. For a planetary case, this perturbation occurs when the
  source trajectory passes the negative perturbation region behind the
  back end of an arrowhead-shaped central caustic. For a binary case,
  a similar perturbation occurs for a source trajectory passing through
  the negative perturbation region between two cusps of an astroid-shaped
  caustic. We demonstrate the degeneracy for two high-magnification events
  of OGLE-2011-BLG-0526 and OGLE-2011-BLG-0950/MOA-2011-BLG-336. For
  OGLE-2011-BLG-0526, the χ<SUP>2</SUP> difference between the planetary
  and binary model is ~3, implying that the degeneracy is very severe. For
  OGLE-2011-BLG-0950/MOA-2011-BLG-336, the stellar binary model is
  formally excluded with Δχ<SUP>2</SUP> ~ 105 and the planetary model is
  preferred. However, it is difficult to claim a planet discovery because
  systematic residuals of data from the planetary model are larger than
  the difference between the planetary and binary models. Considering
  that two events observed during a single season suffer from such a
  degeneracy, it is expected that central perturbations experiencing
  this type of degeneracy is common.

Title: CARMENES. I: instrument and survey overview
Authors: Quirrenbach, Andreas; Amado, Pedro J.; Seifert, Walter;
   Sánchez Carrasco, Miguel A.; Mandel, Holger; Caballero, Jose A.;
   Mundt, Reinhard; Ribas, Ignasi; Reiners, Ansgar; Abril, Miguel;
   Aceituno, Jesus; Alonso-Floriano, Javier; Ammler-von Eiff, Matthias;
   Anglada-Escude, Guillem; Antona Jiménez, Regina; Anwand-Heerwart,
   Heiko; Barrado y Navascués, David; Becerril, Santiago; Bejar,
   Victor; Benitez, Daniel; Cardenas, Concepcion; Claret, Antonio;
   Colome, Josep; Cortés-Contreras, Miriam; Czesla, Stefan; del Burgo,
   Carlos; Doellinger, Michaela; Dorda, R.; Dreizler, Stefan; Feiz,
   Carmen; Fernandez, Matilde; Galadi, David; Garrido, Rafael; González
   Hernández, Jonay; Guardia, Josep; Guenther, Eike; de Guindos, Enrique;
   Gutiérrez-Soto, Juan; Hagen, Hans J.; Hatzes, Artie; Hauschildt,
   Peter; Helmling, Jens; Henning, Thomas; Herrero, Enrique; Huber,
   Armin; Huber, Klaus; Jeffers, Sandra; Joergens, Viki; de Juan,
   Enrique; Kehr, M.; Klutsch, Alexis; Kürster, Martin; Lalitha, S.;
   Laun, Werner; Lemke, Ulrike; Lenzen, Rainer; Lizon, Jean-Louis; López
   del Fresno, Mauro; López-Morales, Mercedes; López-Santiago, Javier;
   Mall, Ulrich; Martin, Eduardo; Martín-Ruiz, Susana; Mirabet, Eduard;
   Montes, David; Morales, Juan Carlos; Morales Muñoz, Rafael; Moya,
   Andres; Naranjo, Vianak; Oreiro, Raquel; Pérez Medialdea, David;
   Pluto, Michael; Rabaza, Ovidio; Ramon, Alejandro; Rebolo, Rafael;
   Reffert, Sabine; Rhode, Petra; Rix, Hans-Walter; Rodler, Florian;
   Rodríguez, Eloy; Rodríguez López, Cristina; Rodríguez Pérez,
   Emilio; Rodriguez Trinidad, A.; Rohloff, Ralf-Reiner; Sánchez-Blanco,
   Ernesto; Sanz-Forcada, Jorge; Schäfer, Sebastian; Schiller, Jörg;
   Schmidt, Christof; Schmitt, Jürgen; Solano, Enrique; Stahl, Otmar;
   Storz, Clemens; Stürmer, Julian; Suarez, Juan Carlos; Thiele, Ulrich;
   Ulbrich, Rainer; Vidal-Dasilva, Manuela; Wagner, Karl; Winkler,
   Johannes; Xu, Wenli; Zapatero Osorio, Maria Rosa; Zechmeister, Mathias
Bibcode: 2012SPIE.8446E..0RQ
Altcode:
  CARMENES (Calar Alto high-Resolution search for M dwarfs with
  Exo-earths with Near-infrared and optical Echelle Spectrographs)
  is a next-generation instrument for the 3.5m telescope at the Calar
  Alto Observatory, built by a consortium of eleven Spanish and German
  institutions. The CARMENES instrument consists of two separate
  échelle spectrographs covering the wavelength range from 0.55 μm
  to 1.7 μm at a spectral resolution of R = 82, 000, fed by fibers
  from the Cassegrain focus of the telescope. Both spectrographs are
  housed in temperature-stabilized vacuum tanks, to enable a long-term
  1 m/s radial velocity precision employing a simultaneous calibration
  with Th-Ne and U-Ne emission line lamps. CARMENES has been optimized
  for a search for terrestrial planets in the habitable zones (HZs)
  of low-mass stars, which may well provide our first chance to study
  environments capable of supporting the development of life outside the
  Solar System. With its unique combination of optical and near-infrared
  ´echelle spectrographs, CARMENES will provide better sensitivity for
  the detection of low-mass planets than any comparable instrument, and
  a powerful tool for discriminating between genuine planet detections
  and false positives caused by stellar activity. The CARMENES survey
  will target 300 M dwarfs in the 2014 to 2018 time frame.

Title: CARMENES. II: optical and opto-mechanical design
Authors: Seifert, W.; Sánchez Carrasco, M. A.; Xu, W.; Cárdenas,
   M. C.; Sánchez-Blanco, E.; Becerril, S.; Feiz, C.; Ramón, A.;
   Dreizler, S.; Rohde, P.; Quirrenbach, A.; Amado, P. J.; Ribas, I.;
   Reiners, A.; Mandel, H.; Caballero, J. A.
Bibcode: 2012SPIE.8446E..33S
Altcode:
  CARMENES is a fiber-fed high-resolution échelle spectrograph for the
  Calar Alto 3.5m telescope. The instrument is built by a German-Spanish
  consortium under the lead of the Landessternwarte Heidelberg. The
  search for planets around M dwarfs with a radial velocity accuracy of
  1 m/s is the main focus of the planned science. Two channels, one for
  the visible, another for the near-infrared, will allow observations
  in the complete wavelength range from 550 to 1700 nm. To ensure the
  stability, the instrument is working in vacuum in a thermally controlled
  environment. The optical design of both channels of the instrument
  and the front-end, as well as the opto-mechanical design, are described.

Title: Characterizing Low-mass Binaries from Observation of
    Long-timescale Caustic-crossing Gravitational Microlensing Events
Authors: Shin, I. -G.; Han, C.; Choi, J. -Y.; Udalski, A.; Sumi, T.;
   Gould, A.; Bozza, V.; Dominik, M.; Fouqué, P.; Horne, K.; Szymański,
   M. K.; Kubiak, M.; Soszyński, I.; Pietrzyński, G.; Poleski,
   R.; Ulaczyk, K.; Pietrukowicz, P.; Kozłowski, S.; Skowron, J.;
   Wyrzykowski, Ł.; OGLE Collaboration; Abe, F.; Bennett, D. P.; Bond,
   I. A.; Botzler, C. S.; Chote, P.; Freeman, M.; Fukui, A.; Furusawa, K.;
   Itow, Y.; Kobara, S.; Ling, C. H.; Masuda, K.; Matsubara, Y.; Miyake,
   N.; Muraki, Y.; Ohmori, K.; Ohnishi, K.; Rattenbury, N. J.; Saito,
   To.; Sullivan, D. J.; Suzuki, D.; Suzuki, K.; Sweatman, W. L.; Takino,
   S.; Tristram, P. J.; Wada, K.; Yock, P. C. M.; MOA Collaboration;
   Bramich, D. M.; Snodgrass, C.; Steele, I. A.; Street, R. A.; Tsapras,
   Y.; RoboNet Collaboration; Alsubai, K. A.; Browne, P.; Burgdorf,
   M. J.; Calchi Novati, S.; Dodds, P.; Dreizler, S.; Fang, X. -S.;
   Grundahl, F.; Gu, C. -H.; Hardis, S.; Harpsøe, K.; Hinse, T. C.;
   Hornstrup, A.; Hundertmark, M.; Jessen-Hansen, J.; Jørgensen, U. G.;
   Kains, N.; Kerins, E.; Liebig, C.; Lund, M.; Lunkkvist, M.; Mancini,
   L.; Mathiasen, M.; Penny, M. T.; Rahvar, S.; Ricci, D.; Scarpetta,
   G.; Skottfelt, J.; Southworth, J.; Surdej, J.; Tregloan-Reed, J.;
   Wambsganss, J.; Wertz, O.; MiNDSTEp Consortium; Almeida, L. A.;
   Batista, V.; Christie, G.; DePoy, D. L.; Dong, Subo; Gaudi, B. S.;
   Henderson, C.; Jablonski, F.; Lee, C. -U.; McCormick, J.; McGregor,
   D.; Moorhouse, D.; Natusch, T.; Ngan, H.; Park, S. -Y.; Pogge, R. W.;
   Tan, T. -G.; Thornley, G.; Yee, J. C.; μFUN Collaboration; Albrow,
   M. D.; Bachelet, E.; Beaulieu, J. -P.; Brillant, S.; Cassan, A.; Cole,
   A. A.; Corrales, E.; Coutures, C.; Dieters, S.; Dominis Prester, D.;
   Donatowicz, J.; Greenhill, J.; Kubas, D.; Marquette, J. -B.; Menzies,
   J. W.; Sahu, K. C.; Zub, M.; PLANET Collaboration
Bibcode: 2012ApJ...755...91S
Altcode: 2012arXiv1204.2869S
  Despite the astrophysical importance of binary star systems,
  detections are limited to those located in small ranges of separations,
  distances, and masses and thus it is necessary to use a variety of
  observational techniques for a complete view of stellar multiplicity
  across a broad range of physical parameters. In this paper, we
  report the detections and measurements of two binaries discovered
  from observations of microlensing events MOA-2011-BLG-090 and
  OGLE-2011-BLG-0417. Determinations of the binary masses are possible by
  simultaneously measuring the Einstein radius and the lens parallax. The
  measured masses of the binary components are 0.43 M <SUB>⊙</SUB> and
  0.39 M <SUB>⊙</SUB> for MOA-2011-BLG-090 and 0.57 M <SUB>⊙</SUB>
  and 0.17 M <SUB>⊙</SUB> for OGLE-2011-BLG-0417 and thus both lens
  components of MOA-2011-BLG-090 and one component of OGLE-2011-BLG-0417
  are M dwarfs, demonstrating the usefulness of microlensing in
  detecting binaries composed of low-mass components. From modeling of
  the light curves considering full Keplerian motion of the lens, we
  also measure the orbital parameters of the binaries. The blended light
  of OGLE-2011-BLG-0417 comes very likely from the lens itself, making
  it possible to check the microlensing orbital solution by follow-up
  radial-velocity observation. For both events, the caustic-crossing parts
  of the light curves, which are critical for determining the physical
  lens parameters, were resolved by high-cadence survey observations
  and thus it is expected that the number of microlensing binaries with
  measured physical parameters will increase in the future.

Title: MOA 2010-BLG-477Lb: Constraining the Mass of a Microlensing
    Planet from Microlensing Parallax, Orbital Motion, and Detection of
    Blended Light
Authors: Bachelet, E.; Shin, I. -G.; Han, C.; Fouqué, P.; Gould, A.;
   Menzies, J. W.; Beaulieu, J. -P.; Bennett, D. P.; Bond, I. A.; Dong,
   Subo; Heyrovský, D.; Marquette, J. -B.; Marshall, J.; Skowron, J.;
   Street, R. A.; Sumi, T.; Udalski, A.; Abe, L.; Agabi, K.; Albrow,
   M. D.; Allen, W.; Bertin, E.; Bos, M.; Bramich, D. M.; Chavez, J.;
   Christie, G. W.; Cole, A. A.; Crouzet, N.; Dieters, S.; Dominik, M.;
   Drummond, J.; Greenhill, J.; Guillot, T.; Henderson, C. B.; Hessman,
   F. V.; Horne, K.; Hundertmark, M.; Johnson, J. A.; Jørgensen, U. G.;
   Kandori, R.; Liebig, C.; Mékarnia, D.; McCormick, J.; Moorhouse,
   D.; Nagayama, T.; Nataf, D.; Natusch, T.; Nishiyama, S.; Rivet,
   J. -P.; Sahu, K. C.; Shvartzvald, Y.; Thornley, G.; Tomczak, A. R.;
   Tsapras, Y.; Yee, J. C.; Batista, V.; Bennett, C. S.; Brillant, S.;
   Caldwell, J. A. R.; Cassan, A.; Corrales, E.; Coutures, C.; Dominis
   Prester, D.; Donatowicz, J.; Kubas, D.; Martin, R.; Williams, A.;
   Zub, M.; PLANET Collaboration; de Almeida, L. Andrade; DePoy, D. L.;
   Gaudi, B. S.; Hung, L. -W.; Jablonski, F.; Kaspi, S.; Klein, N.;
   Lee, C. -U.; Lee, Y.; Koo, J. -R.; Maoz, D.; Muñoz, J. A.; Pogge,
   R. W.; Polishook, D.; Shporer, A.; μFUN Collaboration; Abe, F.;
   Botzler, C. S.; Chote, P.; Freeman, M.; Fukui, A.; Furusawa, K.;
   Harris, P.; Itow, Y.; Kobara, S.; Ling, C. H.; Masuda, K.; Matsubara,
   Y.; Miyake, N.; Ohmori, K.; Ohnishi, K.; Rattenbury, N. J.; Saito,
   To.; Sullivan, D. J.; Suzuki, D.; Sweatman, W. L.; Tristram, P. J.;
   Wada, K.; Yock, P. C. M.; MOA Collaboration; Szymański, M. K.;
   Soszyński, I.; Kubiak, M.; Poleski, R.; Ulaczyk, K.; Pietrzyński,
   G.; Wyrzykowski, Ł.; OGLE Collaboration; Kains, N.; Snodgrass, C.;
   Steele, I. A.; RoboNet Collaboration; Alsubai, K. A.; Bozza, V.;
   Browne, P.; Burgdorf, M. J.; Calchi Novati, S.; Dodds, P.; Dreizler,
   S.; Finet, F.; Gerner, T.; Hardis, S.; Harpsøe, K.; Hinse, T. C.;
   Kerins, E.; Mancini, L.; Mathiasen, M.; Penny, M. T.; Proft, S.;
   Rahvar, S.; Ricci, D.; Scarpetta, G.; Schäfer, S.; Schönebeck, F.;
   Southworth, J.; Surdej, J.; Wambsganss, J.; MiNDSTEp Consortium
Bibcode: 2012ApJ...754...73B
Altcode: 2012arXiv1205.6323B
  Microlensing detections of cool planets are important for the
  construction of an unbiased sample to estimate the frequency of planets
  beyond the snow line, which is where giant planets are thought to
  form according to the core accretion theory of planet formation. In
  this paper, we report the discovery of a giant planet detected from
  the analysis of the light curve of a high-magnification microlensing
  event MOA 2010-BLG-477. The measured planet-star mass ratio is q =
  (2.181 ± 0.004) × 10<SUP>-3</SUP> and the projected separation is
  s = 1.1228 ± 0.0006 in units of the Einstein radius. The angular
  Einstein radius is unusually large θ<SUB>E</SUB> = 1.38 ± 0.11
  mas. Combining this measurement with constraints on the "microlens
  parallax" and the lens flux, we can only limit the host mass to
  the range 0.13 &lt; M/M <SUB>⊙</SUB> &lt; 1.0. In this particular
  case, the strong degeneracy between microlensing parallax and planet
  orbital motion prevents us from measuring more accurate host and planet
  masses. However, we find that adding Bayesian priors from two effects
  (Galactic model and Keplerian orbit) each independently favors the
  upper end of this mass range, yielding star and planet masses of M
  <SUB>*</SUB> = 0.67<SUP>+0.33</SUP> <SUB>- 0.13</SUB> M <SUB>⊙</SUB>
  and m<SUB>p</SUB> = 1.5<SUP>+0.8</SUP> <SUB>- 0.3</SUB> M <SUB>JUP</SUB>
  at a distance of D = 2.3 ± 0.6 kpc, and with a semi-major axis of
  a = 2<SUP>+3</SUP> <SUB>- 1</SUB> AU. Finally, we show that the lens
  mass can be determined from future high-resolution near-IR adaptive
  optics observations independently from two effects, photometric and
  astrometric.

Title: The quest for companions to post-common envelope
    binaries. III. A reexamination of <ASTROBJ>HW Virginis</ASTROBJ>
Authors: Beuermann, K.; Dreizler, S.; Hessman, F. V.; Deller, J.
Bibcode: 2012A&A...543A.138B
Altcode: 2012arXiv1206.3080B
  We report new mid-eclipse times of the short-period sdB/dM binary
  <ASTROBJ>HW Virginis</ASTROBJ>, which differ substantially from the
  times predicted by a previous model. The proposed orbits of the two
  planets in that model are found to be unstable. We present a new
  secularly stable solution, which involves two companions orbiting
  <ASTROBJ>HW Vir</ASTROBJ> with periods of 12.7 yr and 55 ± 15 yr. For
  orbits coplanar with the binary, the inner companion is a giant planet
  with mass M<SUB>3</SUB> sin i<SUB>3</SUB> ≃ 14 M<SUB>Jup</SUB> and the
  outer one a brown dwarf or low-mass star with a mass of M<SUB>4</SUB>
  sin i<SUB>4</SUB> = 30-120 M<SUB>Jup</SUB>. Using the mercury6 code, we
  find that such a system would be stable over more than 10<SUP>7</SUP>
  yr, in spite of the sizeable interaction. Our model fits the observed
  eclipse-time variations by the light-travel time effect alone, without
  invoking any additional process, and provides support for the planetary
  hypothesis of the eclipse-time variations in close binaries. The
  signature of non-Keplerian orbits may be visible in the data.

Title: Characterizing Lenses and Lensed Stars of High-magnification
    Single-lens Gravitational Microlensing Events with Lenses Passing
    over Source Stars
Authors: Choi, J. -Y.; Shin, I. -G.; Park, S. -Y.; Han, C.; Gould,
   A.; Sumi, T.; Udalski, A.; Beaulieu, J. -P.; Street, R.; Dominik, M.;
   Allen, W.; Almeida, L. A.; Bos, M.; Christie, G. W.; Depoy, D. L.;
   Dong, S.; Drummond, J.; Gal-Yam, A.; Gaudi, B. S.; Henderson, C. B.;
   Hung, L. -W.; Jablonski, F.; Janczak, J.; Lee, C. -U.; Mallia, F.;
   Maury, A.; McCormick, J.; McGregor, D.; Monard, L. A. G.; Moorhouse,
   D.; Muñoz, J. A.; Natusch, T.; Nelson, C.; Park, B. -G.; Pogge, R. W.;
   "TG" Tan, T. -G.; Thornley, G.; Yee, J. C.; μFUN Collaboration; Abe,
   F.; Barnard, E.; Baudry, J.; Bennett, D. P.; Bond, I. A.; Botzler,
   C. S.; Freeman, M.; Fukui, A.; Furusawa, K.; Hayashi, F.; Hearnshaw,
   J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.; Kilmartin, P. M.; Kobara, S.;
   Korpela, A.; Lin, W.; Ling, C. H.; Makita, S.; Masuda, K.; Matsubara,
   Y.; Miyake, N.; Muraki, Y.; Nagaya, M.; Nishimoto, K.; Ohnishi, K.;
   Okumura, T.; Omori, K.; Perrott, Y. C.; Rattenbury, N.; Saito, To.;
   Skuljan, L.; Sullivan, D. J.; Suzuki, D.; Suzuki, K.; Sweatman,
   W. L.; Takino, S.; Tristram, P. J.; Wada, K.; Yock, P. C. M.;
   MOA Collaboration; Szymański, M. K.; Kubiak, M.; Pietrzyński,
   G.; Soszyński, I.; Poleski, R.; Ulaczyk, K.; Wyrzykowski, Ł.;
   Kozłowski, S.; Pietrukowicz, P.; OGLE Collaboration; Albrow, M. D.;
   Bachelet, E.; Batista, V.; Bennett, C. S.; Bowens-Rubin, R.; Brillant,
   S.; Cassan, A.; Cole, A.; Corrales, E.; Coutures, Ch.; Dieters, S.;
   Dominis Prester, D.; Donatowicz, J.; Fouqué, P.; Greenhill, J.;
   Kane, S. R.; Menzies, J.; Sahu, K. C.; Wambsganss, J.; Williams, A.;
   Zub, M.; PLANET Collaboration; Allan, A.; Bramich, D. M.; Browne, P.;
   Clay, N.; Fraser, S.; Horne, K.; Kains, N.; Mottram, C.; Snodgrass,
   C.; Steele, I.; Tsapras, Y.; RoboNet Collaboration; Alsubai, K. A.;
   Bozza, V.; Burgdorf, M. J.; Calchi Novati, S.; Dodds, P.; Dreizler,
   S.; Finet, F.; Gerner, T.; Glitrup, M.; Grundahl, F.; Hardis, S.;
   Harpsøe, K.; Hinse, T. C.; Hundertmark, M.; Jørgensen, U. G.;
   Kerins, E.; Liebig, C.; Maier, G.; Mancini, L.; Mathiasen, M.; Penny,
   M. T.; Proft, S.; Rahvar, S.; Ricci, D.; Scarpetta, G.; Schäfer, S.;
   Schönebeck, F.; Skottfelt, J.; Surdej, J.; Southworth, J.; Zimmer,
   F.; MiNDSTEp Consortium
Bibcode: 2012ApJ...751...41C
Altcode: 2011arXiv1111.4032C
  We present the analysis of the light curves of nine high-magnification
  single-lens gravitational microlensing events with lenses passing
  over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176,
  MOA-2007-BLG-233/OGLE-2007-BLG-302, MOA-2009-BLG-174, MOA-2010-BLG-436,
  MOA-2011-BLG-093, MOA-2011-BLG-274, OGLE-2011-BLG-0990/MOA-2011-BLG-300,
  and OGLE-2011-BLG-1101/MOA-2011-BLG-325. For all of the events, we
  measure the linear limb-darkening coefficients of the surface brightness
  profile of source stars by measuring the deviation of the light curves
  near the peak affected by the finite-source effect. For seven events,
  we measure the Einstein radii and the lens-source relative proper
  motions. Among them, five events are found to have Einstein radii
  of less than 0.2 mas, making the lenses very low mass star or brown
  dwarf candidates. For MOA-2011-BLG-274, especially, the small Einstein
  radius of θ<SUB>E</SUB> ~ 0.08 mas combined with the short timescale
  of t <SUB>E</SUB> ~ 2.7 days suggests the possibility that the lens
  is a free-floating planet. For MOA-2009-BLG-174, we measure the lens
  parallax and thus uniquely determine the physical parameters of the
  lens. We also find that the measured lens mass of ~0.84 M <SUB>⊙</SUB>
  is consistent with that of a star blended with the source, suggesting
  that the blend is likely to be the lens. Although we did not find
  planetary signals for any of the events, we provide exclusion diagrams
  showing the confidence levels excluding the existence of a planet as
  a function of the separation and mass ratio.

Title: KIC 4247791: a SB4 system with two eclipsing binaries (2EBs). A
    quadruple system?
Authors: Lehmann, H.; Zechmeister, M.; Dreizler, S.; Schuh, S.;
   Kanzler, R.
Bibcode: 2012A&A...541A.105L
Altcode: 2012arXiv1202.6552L
  Context. KIC 4247791 is an eclipsing binary observed by the Kepler
  satellite mission. <BR /> Aims: We wish to determine the nature of
  its components and in particular the origin of a shallow dip in its
  Kepler light curve that previous investigations have been unable to
  explain in a unique way. <BR /> Methods: We analyse newly obtained
  high-resolution spectra of the star using synthetic spectra based
  on atmosphere models, derive the radial velocities of the stellar
  components from cross-correlation with a synthetic template, and
  calculate the orbital solution. We use the JKTEBOP program to model the
  Kepler light curve of KIC 4247791. <BR /> Results: We find KIC 4247791
  to be a SB4 star. The radial velocity variations of its four components
  can be explained by two separate eclipsing binaries. In contradiction
  to previous photometric findings, we show that the observed composite
  spectrum as well as the derived masses of all four of its components
  correspond to spectral type F. <BR /> Conclusions: The observed small
  dip in the light curve is not caused by a transit-like phenomenon but
  by the eclipses of the second binary system. We find evidence that
  KIC 4247791 might belong to the very rare hierarchical SB4 systems
  with two eclipsing binaries. <P />Based on observations with the 2-m
  Alfred-Jensch-Telescope of the Thüringer Landessternwarte Tautenburg.

Title: VizieR Online Data Catalog: Planetary transit candidates in
    CoRoT LRa01 field (Carone+, 2012)
Authors: Carone, L.; Gandolfi, D.; Cabrera, J.; Hatzes, A. P.; Deeg,
   H. J.; Csizmadia, Sz.; Paetzold, M.; Weingrill, J.; Aigrain, S.;
   Alonso, R.; Alapini, A.; Almenara, J. -M.; Auvergne, M.; Baglin, A.;
   Barge, P.; Bonomo, A. S.; Borde, P.; Bouchy, F.; Bruntt, H.; Carpano,
   S.; Cochran, W. D.; Deleuil, M.; Diaz, R. F.; Dreizler, S.; Dvorak, R.;
   Eisloeffel, J.; Eigmueller, P.; Endl, M.; Erikson, A.; Ferraz-Mello,
   S.; Fridlund, M.; Gazzano, J. -C.; Gibson, N.; Gillon, M.; Gondoin,
   P.; Grziwa, S.; Guenther, E. W.; Guillot, T.; Hartmann, M.; Havel, M.;
   Hebrard, G.; Jorda, L.; Kabath, P.; Leger, A.; Llebaria, A.; Lammer,
   H.; Lovis, C.; MacQueen, P. J.; Mayor, M.; Mazeh, T.; Moutou, C.;
   Nortmann, L.; Ofir, A.; Ollivier, M.; Parviainen, H.; Pepe, F.; Pont,
   F.; Queloz, D.; Rabus, M.; Rauer, H.; Regulo, C.; Renner, S.; de La,
   Reza R.; Rouan, D.; Santerne, A.; Samuel, B.; Schneider, J.; Shporer,
   A.; Stecklum, B.; Tal-Or, L.; Tingley, B.; Udry, S.; Wuchterl, G.
Bibcode: 2012yCat..35380112C
Altcode: 2012yCat..35389112C
  We present the list of planetary transit candidates from the CoRoT
  LRa01 star field in the Monoceros constellation toward the Galactic
  anti-center direction. The CoRoT observations of LRa01 lasted from
  24 October 2007 to 3 March 2008. <P />We acquired and analyzed 7470
  chromatic and 3938 monochromatic lightcurves. Instrumental noise
  and stellar variability were treated with several filtering tools by
  different teams from the CoRoT community. Different transit search
  algorithms were applied to the lightcurves. <P />(4 data files).

Title: The quest for companions to post-common envelope
    binaries. II. NSVS14256825 and HS0705+6700
Authors: Beuermann, K.; Breitenstein, P.; Debski, B.; Diese, J.;
   Dubovsky, P. A.; Dreizler, S.; Hessman, F. V.; Hornoch, K.; Husser,
   T. -O.; Pojmanski, G.; Wolf, M.; Woźniak, P. R.; Zasche, P.; Denk,
   B.; Langer, M.; Wagner, C.; Wahrenberg, D.; Bollmann, T.; Habermann,
   F. N.; Haustovich, N.; Lauser, M.; Liebing, F.; Niederstadt, F.
Bibcode: 2012A&A...540A...8B
Altcode: 2012arXiv1202.5990B
  We report new mid-eclipse times of the two close binaries NSVS14256825
  and HS0705+6700, harboring an sdB primary and a low-mass main-sequence
  secondary. Both objects display clear variations in their measured
  orbital period, which can be explained by the action of a third object
  orbiting the binary. If this interpretation is correct, the third
  object in NSVS14256825 is a giant planet with a mass of roughly 12
  M<SUB>Jup</SUB>. For HS0705+6700, we provide evidence that strengthens
  the case for the suggested periodic nature of the eclipse time variation
  and reduces the uncertainties in the parameters of the brown dwarf
  implied by that model. The derived period is 8.4 yr and the mass is
  31 M<SUB>Jup</SUB>, if the orbit is coplanar with the binary. This
  research is part of the PlanetFinders project, an ongoing collaboration
  between professional astronomers and student groups at high schools.

Title: News of the MUSE
Authors: Bacon, R.; Accardo, M.; Adjali, L.; Anwand, H.; Bauer, S. -M.;
   Blaizot, J.; Boudon, D.; Brinchmann, J.; Brotons, L.; Caillier, P.;
   Capoani, L.; Carollo, M.; Comin, M.; Contini, T.; Cumani, C.; Daguis,
   E.; Deiries, S.; Delabre, B.; Dreizler, S.; Dubois, J. -P.; Dupieux,
   M.; Dupuy, C.; Emsellem, E.; Fleischmann, A.; François, M.; Gallou,
   G.; Gharsa, T.; Girard, N.; Glindemann, A.; Guiderdoni, B.; Hahn,
   T.; Hansali, G.; Hofmann, D.; Jarno, A.; Kelz, A.; Kiekebusch, M.;
   Knudstrup, J.; Koehler, C.; Kollatschny, W.; Kosmalski, J.; Laurent,
   F.; Le Floch, M.; Lilly, S.; Lizon à L'Allemand, J. -L.; Loupias,
   M.; Manescau, A.; Monstein, C.; Nicklas, H.; Niemeyer, J.; Olaya,
   J. -C.; Palsa, R.; Parès, L.; Pasquini, L.; Pécontal-Rousset, A.;
   Pello, R.; Petit, C.; Piqueras, L.; Popow, E.; Reiss, R.; Remillieux,
   A.; Renault, E.; Rhode, P.; Richard, J.; Roth, J.; Rupprecht, G.;
   Schaye, J.; Slezak, E.; Soucail, G.; Steinmetz, M.; Streicher, O.;
   Stuik, R.; Valentin, H.; Vernet, J.; Weilbacher, P.; Wisotzki, L.;
   Yerle, N.; Zins, G.
Bibcode: 2012Msngr.147....4B
Altcode:
  We report on progress of the Multi Unit Spectroscopic Explorer (MUSE),
  a second generation VLT panoramic integral field spectrograph. MUSE
  is now in its final phase of integration, testing and validation in
  Europe. The instrument is described and some results of its measured
  performance are shown.

Title: Microlensing Binaries Discovered through High-magnification
    Channel
Authors: Shin, I. -G.; Choi, J. -Y.; Park, S. -Y.; Han, C.; Gould, A.;
   Sumi, T.; Udalski, A.; Beaulieu, J. -P.; Dominik, M.; Allen, W.; Bos,
   M.; Christie, G. W.; Depoy, D. L.; Dong, S.; Drummond, J.; Gal-Yam,
   A.; Gaudi, B. S.; Hung, L. -W.; Janczak, J.; Kaspi, S.; Lee, C. -U.;
   Mallia, F.; Maoz, D.; Maury, A.; McCormick, J.; Monard, L. A. G.;
   Moorhouse, D.; Muñoz, J. A.; Natusch, T.; Nelson, C.; Park, B. -G.;
   Pogge, R. W.; Polishook, D.; Shvartzvald, Y.; Shporer, A.; Thornley,
   G.; Yee, J. C.; μFUN Collaboration; Abe, F.; Bennett, D. P.; Bond,
   I. A.; Botzler, C. S.; Fukui, A.; Furusawa, K.; Hayashi, F.; Hearnshaw,
   J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.; Kilmartin, P. M.; Kobara, S.;
   Korpela, A.; Lin, W.; Ling, C. H.; Makita, S.; Masuda, K.; Matsubara,
   Y.; Miyake, N.; Muraki, Y.; Nagaya, M.; Nishimoto, K.; Ohnishi, K.;
   Okumura, T.; Omori, K.; Perrott, Y. C.; Rattenbury, N.; Saito, To.;
   Skuljan, L.; Sullivan, D. J.; Suzuki, D.; Sweatman, W. L.; Tristram,
   P. J.; Wada, K.; Yock, P. C. M.; MOA Collaboration; Szymański,
   M. K.; Kubiak, M.; Pietrzyński, G.; Soszyński, I.; Poleski, R.;
   Ulaczyk, K.; Wyrzykowski, Ł.; Kozłowski, S.; Pietrukowicz, P.; OGLE
   Collaboration; Albrow, M. D.; Batista, V.; Bramich, D. M.; Brillant,
   S.; Caldwell, J. A. R.; Calitz, J. J.; Cassan, A.; Cole, A.; Cook,
   K. H.; Corrales, E.; Coutures, Ch.; Dieters, S.; Dominis Prester, D.;
   Donatowicz, J.; Fouqué, P.; Greenhill, J.; Hoffman, M.; Jørgensen,
   U. G.; Kane, S. R.; Kubas, D.; Marquette, J. -B.; Martin, R.; Meintjes,
   P.; Menzies, J.; Pollard, K. R.; Sahu, K. C.; Wambsganss, J.; Williams,
   A.; Vinter, C.; Zub, M.; PLANET Collaboration; Allan, A.; Browne, P.;
   Horne, K.; Snodgrass, C.; Steele, I.; Street, R.; Tsapras, Y.; RoboNet
   Collaboration; Alsubai, K. A.; Bozza, V.; Browne, P.; Burgdorf, M. J.;
   Calchi Novati, S.; Dodds, P.; Dreizler, S.; Finet, F.; Gerner, T.;
   Glitrup, M.; Grundahl, F.; Hardis, S.; Harpsøe, K.; Hessman, F. V.;
   Hinse, T. C.; Hundertmark, M.; Kains, N.; Kerins, E.; Liebig, C.;
   Maier, G.; Mancini, L.; Mathiasen, M.; Penny, M. T.; Proft, S.; Rahvar,
   S.; Ricci, D.; Scarpetta, G.; Schäfer, S.; Schönebeck, F.; Skottfelt,
   J.; Surdej, J.; Southworth, J.; Zimmer, F.; MiNDSTEp Consortium
Bibcode: 2012ApJ...746..127S
Altcode: 2011arXiv1109.3295S
  Microlensing can provide a useful tool to probe binary distributions
  down to low-mass limits of binary companions. In this paper, we analyze
  the light curves of eight binary-lensing events detected through the
  channel of high-magnification events during the seasons from 2007 to
  2010. The perturbations, which are confined near the peak of the light
  curves, can be easily distinguished from the central perturbations
  caused by planets. However, the degeneracy between close and wide binary
  solutions cannot be resolved with a 3σ confidence level for three
  events, implying that the degeneracy would be an important obstacle
  in studying binary distributions. The dependence of the degeneracy on
  the lensing parameters is consistent with a theoretical prediction
  that the degeneracy becomes severe as the binary separation and the
  mass ratio deviate from the values of resonant caustics. The measured
  mass ratio of the event OGLE-2008-BLG-510/MOA-2008-BLG-369 is q ~ 0.1,
  making the companion of the lens a strong brown dwarf candidate.

Title: The quest for companions to post-common envelope
    binaries. I. Searching a sample of stars from the CSS and SDSS
Authors: Backhaus, U.; Bauer, S.; Beuermann, K.; Diese, J.; Dreizler,
   S.; Hessman, F. V.; Husser, T. -O.; Klapdohr, K. -H.; Möllmanns, J.;
   Schünecke, R.; Dette, J.; Dubbert, J.; Miosga, T.; Rochus Vogel,
   A. L.; Simons, S.; Biriuk, S.; Debrah, M.; Griemens, M.; Hahn, A.;
   Möller, T.; Pawlowski, M.; Schweizer, M.; Speck, A. -L.; Zapros, C.;
   Bollmann, T.; Habermann, F. N.; Haustovich, N.; Lauser, M.; Liebing,
   F.; Niederstadt, F.; Hoppen, K.; Kindermann, D.; Küppers, F.; Rauch,
   B.; Althoff, F.; Horstmann, M.; Kellerman, J. N.; Kietz, R.; Nienaber,
   T.; Sauer, M.; Secci, A.; Wüllner, L.
Bibcode: 2012A&A...538A..84B
Altcode: 2012arXiv1201.2098B
  As part of an ongoing collaboration between student groups at high
  schools and professional astronomers, we have searched for the presence
  of circum-binary planets in a bona-fide unbiased sample of twelve
  post-common envelope binaries (PCEBs) from the Catalina Sky Survey
  (CSS) and the Sloan Digital Sky Survey (SDSS). Although the present
  ephemerides are significantly more accurate than previous ones, we
  find no clear evidence for orbital period variations between 2005 and
  2011 or during the 2011 observing season. The sparse long-term coverage
  still permits O-C variations with a period of years and an amplitude of
  tens of seconds, as found in other systems. Our observations provide the
  basis for future inferences about the frequency with which planet-sized
  or brown-dwarf companions have either formed in these evolved systems
  or survived the common envelope (CE) phase.

Title: Planetary transit candidates in the CoRoT LRa01 field
Authors: Carone, L.; Gandolfi, D.; Cabrera, J.; Hatzes, A. P.; Deeg,
   H. J.; Csizmadia, Sz.; Pätzold, M.; Weingrill, J.; Aigrain, S.;
   Alonso, R.; Alapini, A.; Almenara, J. -M.; Auvergne, M.; Baglin,
   A.; Barge, P.; Bonomo, A. S.; Bordé, P.; Bouchy, F.; Bruntt, H.;
   Carpano, S.; Cochran, W. D.; Deleuil, M.; Díaz, R. F.; Dreizler,
   S.; Dvorak, R.; Eislöffel, J.; Eigmüller, P.; Endl, M.; Erikson,
   A.; Ferraz-Mello, S.; Fridlund, M.; Gazzano, J. -C.; Gibson, N.;
   Gillon, M.; Gondoin, P.; Grziwa, S.; Günther, E. W.; Guillot, T.;
   Hartmann, M.; Havel, M.; Hébrard, G.; Jorda, L.; Kabath, P.; Léger,
   A.; Llebaria, A.; Lammer, H.; Lovis, C.; MacQueen, P. J.; Mayor,
   M.; Mazeh, T.; Moutou, C.; Nortmann, L.; Ofir, A.; Ollivier, M.;
   Parviainen, H.; Pepe, F.; Pont, F.; Queloz, D.; Rabus, M.; Rauer,
   H.; Régulo, C.; Renner, S.; de La Reza, R.; Rouan, D.; Santerne,
   A.; Samuel, B.; Schneider, J.; Shporer, A.; Stecklum, B.; Tal-Or,
   L.; Tingley, B.; Udry, S.; Wuchterl, G.
Bibcode: 2012A&A...538A.112C
Altcode: 2011arXiv1110.2384C
  Context. CoRoT is a pioneering space mission whose primary goals are
  stellar seismology and extrasolar planets search. Its surveys of large
  stellar fields generate numerous planetary candidates whose lightcurves
  have transit-like features. An extensive analytical and observational
  follow-up effort is undertaken to classify these candidates. <BR
  /> Aims: We present the list of planetary transit candidates from
  the CoRoT LRa01 star field in the Monoceros constellation toward the
  Galactic anti-center direction. The CoRoT observations of LRa01 lasted
  from 24 October 2007 to 3 March 2008. <BR /> Methods: We acquired and
  analyzed 7470 chromatic and 3938 monochromatic lightcurves. Instrumental
  noise and stellar variability were treated with several filtering
  tools by different teams from the CoRoT community. Different transit
  search algorithms were applied to the lightcurves. <BR /> Results:
  Fifty-one stars were classified as planetary transit candidates
  in LRa01. Thirty-seven (i.e., 73% of all candidates) are "good"
  planetary candidates based on photometric analysis only. Thirty-two
  (i.e., 87% of the "good" candidates) have been followed-up. At the
  time of writing twenty-two cases were solved and five planets were
  discovered: three transiting hot-Jupiters (CoRoT-5b, CoRoT-12b,
  and CoRoT-21b), the first terrestrial transiting planet (CoRoT-7b),
  and another planet in the same system (CoRoT-7c, detected by radial
  velocity survey only). Evidence of another non-transiting planet in
  the CoRoT-7 system, namely CoRoT-7d, was recently found as well. <P
  />The CoRoT space mission, launched on December 27, 2006, has been
  developed and is operated by CNES, with contributions of Austria,
  Belgium, Brazil, ESA (RSSD and Science Program), Germany and Spain.

Title: Transiting exoplanets from the CoRoT space
mission. XXI. CoRoT-19b: a low density planet orbiting an old
    inactive F9V-star
Authors: Guenther, E. W.; Díaz, R. F.; Gazzano, J. -C.; Mazeh,
   T.; Rouan, D.; Gibson, N.; Csizmadia, Sz.; Aigrain, S.; Alonso, R.;
   Almenara, J. M.; Auvergne, M.; Baglin, A.; Barge, P.; Bonomo, A. S.;
   Bordé, P.; Bouchy, F.; Bruntt, H.; Cabrera, J.; Carone, L.; Carpano,
   S.; Cavarroc, C.; Deeg, H. J.; Deleuil, M.; Dreizler, S.; Dvorak, R.;
   Erikson, A.; Ferraz-Mello, S.; Fridlund, M.; Gandolfi, D.; Gillon, M.;
   Guillot, T.; Hatzes, A.; Havel, M.; Hébrard, G.; Jehin, E.; Jorda,
   L.; Lammer, H.; Léger, A.; Moutou, C.; Nortmann, L.; Ollivier, M.;
   Ofir, A.; Pasternacki, Th.; Pätzold, M.; Parviainen, H.; Queloz,
   D.; Rauer, H.; Samuel, B.; Santerne, A.; Schneider, J.; Tal-Or, L.;
   Tingley, B.; Weingrill, J.; Wuchterl, G.
Bibcode: 2012A&A...537A.136G
Altcode: 2011arXiv1112.1035G
  Context. Observations of transiting extrasolar planets are of key
  importance to our understanding of planets because their mass, radius,
  and mass density can be determined. These measurements indicate that
  planets of similar mass can have very different radii. For low-density
  planets, it is generally assumed that they are inflated owing to their
  proximity to the host-star. To determine the causes of this inflation,
  it is necessary to obtain a statistically significant sample of planets
  with precisely measured masses and radii. <BR /> Aims: The CoRoT space
  mission allows us to achieve a very high photometric accuracy. By
  combining CoRoT data with high-precision radial velocity measurements,
  we derive precise planetary radii and masses. We report the discovery
  of CoRoT-19b, a gas-giant planet transiting an old, inactive F9V-type
  star with a period of four days. <BR /> Methods: After excluding
  alternative physical configurations mimicking a planetary transit
  signal, we determine the radius and mass of the planet by combining
  CoRoT photometry with high-resolution spectroscopy obtained with the
  echelle spectrographs SOPHIE, HARPS, FIES, and SANDIFORD. To improve
  the precision of its ephemeris and the epoch, we observed additional
  transits with the TRAPPIST and Euler telescopes. Using HARPS spectra
  obtained during the transit, we then determine the projected angle
  between the spin of the star and the orbit of the planet. <BR />
  Results: We find that the host star of CoRoT-19b is an inactive
  F9V-type star close to the end of its main-sequence life. The host star
  has a mass M<SUB>∗</SUB> = 1.21 ± 0.05 M<SUB>⊙</SUB> and radius
  R<SUB>∗</SUB> = 1.65 ± 0.04 R<SUB>⊙</SUB>. The planet has a mass of
  M<SUB>P</SUB> = 1.11 ± 0.06 M<SUB>Jup</SUB> and radius of R<SUB>P</SUB>
  = 1.29 ± 0.03 R<SUB>Jup</SUB>. The resulting bulk density is only ρ
  = 0.71 ± 0.06 g cm<SUP>-3</SUP>, which is much lower than that for
  Jupiter. <BR /> Conclusions: The exoplanet CoRoT-19b is an example of
  a giant planet of almost the same mass as Jupiter but a ≈30% larger
  radius. <P />The CoRoT space mission, launched on December 27, 2006,
  has been developed and is operated by the CNES, with the contribution of
  Austria, Belgium, Brazil, ESA (RSSD and Science Program), Germany and
  Spain. Partly based on observations obtained at the European Southern
  Observatory at Paranal, Chile in program 184.C-0639, and partly based
  on observations conducted at McDonald Observatory.

Title: A new extensive library of synthetic stellar spectra from
    PHOENIX atmospheres and its application to fitting VLT MUSE spectra
Authors: Husser, T. -O.; Kamann, S.; Dreizler, S.; Hauschildt, Peter H.
Bibcode: 2012ASInC...6...71H
Altcode: 2012arXiv1203.1941H
  We present a new library of synthetic spectra based on the stellar
  atmosphere code phx. It covers the wavelength range from 500 Å to
  55 000 Å with a resolution of R=500 000 in the optical and near IR,
  R=100 000 in the IR and &amp;Delta&amp;;lambda;=0.1 Å in the UV. The
  parameter space covers 2 300 K ≤ T_{eff} ≤ 8 000 K, 0.0 ≤ log(g)
  ≤ +6.0, -4.0 ≤ [Fe/H] ≤ +1.0 and -0.3 ≤ [α/Fe] ≤ +0.8. The
  library is work-in-progress and going to be extended to at least
  T_{eff}=25 000 K. We use a new self-consistent way of describing
  the microturbulence for our model atmospheres. The entire library
  of synthetic spectra will be available for download. Furthermore we
  present a method for fitting spectra, especially designed to work
  with the new 2nd generation VLT instrument muse. We show that we can
  determine stellar parameters (T_{eff}, log(g), [Fe/H] and [α/Fe])
  and even single element abundances.

Title: Evidence for planets in post-common envelope binaries
Authors: Dreizler, S.; Beuermann, K.; Hesman, F. V.
Bibcode: 2012MmSAI..83..498D
Altcode:
  In the recent years, several circum-binary planets orbiting post-common
  envelope systems have been announced. Some of the derived planetary
  parameters have been questioned by others. We therefore present an
  investigation of the current status in this dynamically evolving
  field. False positive scenarios for the eclipse time variations are
  therefore discussed. We also present an update on new measurements on
  NN Ser and shortly address the quest for the frequency of planets in
  post-common envelope systems.

Title: Discovery and Mass Measurements of a Cold, 10 Earth Mass
    Planet and Its Host Star
Authors: Muraki, Y.; Han, C.; Bennett, D. P.; Suzuki, D.; Monard,
   L. A. G.; Street, R.; Jorgensen, U. G.; Kundurthy, P.; Skowron, J.;
   Becker, A. C.; Albrow, M. D.; Fouqué, P.; Heyrovský, D.; Barry,
   R. K.; Beaulieu, J. -P.; Wellnitz, D. D.; Bond, I. A.; Sumi, T.;
   Dong, S.; Gaudi, B. S.; Bramich, D. M.; Dominik, M.; Abe, F.; Botzler,
   C. S.; Freeman, M.; Fukui, A.; Furusawa, K.; Hayashi, F.; Hearnshaw,
   J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.; Korpela, A. V.; Kilmartin,
   P. M.; Lin, W.; Ling, C. H.; Makita, S.; Masuda, K.; Matsubara, Y.;
   Miyake, N.; Nishimoto, K.; Ohnishi, K.; Perrott, Y. C.; Rattenbury,
   N. J.; Saito, To.; Skuljan, L.; Sullivan, D. J.; Sweatman, W. L.;
   Tristram, P. J.; Wada, K.; Yock, P. C. M.; MOA Collaboration;
   Christie, G. W.; DePoy, D. L.; Gorbikov, E.; Gould, A.; Kaspi, S.;
   Lee, C. -U.; Mallia, F.; Maoz, D.; McCormick, J.; Moorhouse, D.;
   Natusch, T.; Park, B. -G.; Pogge, R. W.; Polishook, D.; Shporer, A.;
   Thornley, G.; Yee, J. C.; μFUN Collaboration; Allan, A.; Browne,
   P.; Horne, K.; Kains, N.; Snodgrass, C.; Steele, I.; Tsapras, Y.;
   RoboNet Collaboration; Batista, V.; Bennett, C. S.; Brillant, S.;
   Caldwell, J. A. R.; Cassan, A.; Cole, A.; Corrales, R.; Coutures,
   Ch.; Dieters, S.; Dominis Prester, D.; Donatowicz, J.; Greenhill,
   J.; Kubas, D.; Marquette, J. -B.; Martin, R.; Menzies, J.; Sahu,
   K. C.; Waldman, I.; Williams, A.; Zub, M.; PLANET Collaboration;
   Bourhrous, H.; Matsuoka, Y.; Nagayama, T.; Oi, N.; Randriamanakoto,
   Z.; IRSF Observers; Bozza, V.; Burgdorf, M. J.; Calchi Novati, S.;
   Dreizler, S.; Finet, F.; Glitrup, M.; Harpsøe, K.; Hinse, T. C.;
   Hundertmark, M.; Liebig, C.; Maier, G.; Mancini, L.; Mathiasen, M.;
   Rahvar, S.; Ricci, D.; Scarpetta, G.; Skottfelt, J.; Surdej, J.;
   Southworth, J.; Wambsganss, J.; Zimmer, F.; MiNDSTEp Consortium;
   Udalski, A.; Poleski, R.; Wyrzykowski, Ł.; Ulaczyk, K.; Szymański,
   M. K.; Kubiak, M.; Pietrzyński, G.; Soszyński, I.; OGLE Collaboration
Bibcode: 2011ApJ...741...22M
Altcode: 2011arXiv1106.2160M
  We present the discovery and mass measurement of the cold,
  low-mass planet MOA-2009-BLG-266Lb, performed with the gravitational
  microlensing method. This planet has a mass of m<SUB>p</SUB> = 10.4 ±
  1.7 M<SUB>⊕</SUB> and orbits a star of mass M <SUB>sstarf</SUB> = 0.56
  ± 0.09 M<SUB>sun</SUB> at a semimajor axis of a = 3.2{+1.9\atop -0.5}
  AU and an orbital period of P = 7.6{+7.7\atop -1.5} yrs. The planet
  and host star mass measurements are enabled by the measurement of the
  microlensing parallax effect, which is seen primarily in the light curve
  distortion due to the orbital motion of the Earth. But the analysis
  also demonstrates the capability to measure the microlensing parallax
  with the Deep Impact (or EPOXI) spacecraft in a heliocentric orbit. The
  planet mass and orbital distance are similar to predictions for the
  critical core mass needed to accrete a substantial gaseous envelope,
  and thus may indicate that this planet is a "failed" gas giant. This
  and future microlensing detections will test planet formation theory
  predictions regarding the prevalence and masses of such planets.

Title: CAFE: Calar Alto Fiber-fed Echelle spectrograph
Authors: Sánchez, S. F.; Aceituno, J.; Thiele, U.; Grupp, F.;
   Dreizler, S.; Bean, J.; Benitez, D.
Bibcode: 2011hsa6.conf..783S
Altcode:
  The Calar Alto Fiber-fed Echelle spectrograph (CAFE) is an instrument
  underconstruction at CAHA to replace FOCES, the high-resolution
  echellespectrograph at the 2.2 m telescope of the observatory. FOCES
  is a property ofthe Observatory of the Munich University, and it
  was recalled it from Calar Altoin 2009. The instrument comprised
  a substantial fraction of thetelescope time during its operational
  life-time, and it is due to that it wastaken the decision to build
  a replacement.CAFE shares its basic characteristics with those of
  FOCES. However, significantimprovements have been introduced in
  the original design, the quality of thematerials, and the overall
  stability of the system. In particular: (i) a newcalibration Iodine
  cell is foreseen to operate together with the standard ThArlamps;
  (ii) the optical quality of all the components has been selected to
  belambda/20, instead of the original lambda/10; (iii) an isolated room
  hasbeen selected to place the instrument, termalized and stabilized
  againstvibrations (extensive tests have been performed to grant the
  stability); (iv)most of the mobile parts in FOCES has been substituted
  by fixed elements, toincrease the stability of the system; and finally
  (v) a new more efficientCCD, with a smaller pixel has been acquired. It
  is expected that the overallefficiency and the quality of the data will
  be significantly improved withrespect to its precesor. In particular,
  CAFE is design and built to achieveresolutions of R ∼ 70000, which
  will be kept in the final acquired data,allowing it to compete with
  current operational extrasolar planets hunters.After two years of work
  all the components are in place. The instrument is nowfinally assembled,
  and we are performing the the first alignment tests. It isexpected that
  the commissioning on the laboratory will finish at the end of2010,
  followed by the commissioning on telescope along the first semester
  of2011. If everything goes well, we will offer the instrument in a
  shared-riskmode for the second semester of 2011.

Title: MOA-2009-BLG-387Lb: a massive planet orbiting an M dwarf
Authors: Batista, V.; Gould, A.; Dieters, S.; Dong, S.; Bond, I.;
   Beaulieu, J. P.; Maoz, D.; Monard, B.; Christie, G. W.; McCormick,
   J.; Albrow, M. D.; Horne, K.; Tsapras, Y.; Burgdorf, M. J.; Calchi
   Novati, S.; Skottfelt, J.; Caldwell, J.; Kozłowski, S.; Kubas, D.;
   Gaudi, B. S.; Han, C.; Bennett, D. P.; An, J.; MOA Collaboration; Abe,
   F.; Botzler, C. S.; Douchin, D.; Freeman, M.; Fukui, A.; Furusawa,
   K.; Hearnshaw, J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.; Kilmartin,
   P. M.; Korpela, A.; Lin, W.; Ling, C. H.; Makita, B. S.; Masuda, K.;
   Matsubara, Y.; Miyake, N.; Muraki, Y.; Nagaya, M.; Nishimoto, K.;
   Ohnishi, K.; Okumura, T.; Perrott, Y. C.; Rattenbury, N.; Saito,
   To.; Sullivan, D. J.; Sumi, T.; Sweatman, W. L.; Tristram, P. J.;
   von Seggern, E.; Yock, P. C. M.; PLANET Collaboration; Brillant, S.;
   Calitz, J. J.; Cassan, A.; Cole, A.; Cook, K.; Coutures, C.; Dominis
   Prester, D.; Donatowicz, J.; Greenhill, J.; Hoffman, M.; Jablonski,
   F.; Kane, S. R.; Kains, N.; Marquette, J. -B.; Martin, R.; Martioli,
   E.; Meintjes, P.; Menzies, J.; Pedretti, E.; Pollard, K.; Sahu, K. C.;
   Vinter, C.; Wambsganss, J.; Watson, R.; Williams, A.; Zub, M.; FUN
   Collaboration; Allen, W.; Bolt, G.; Bos, M.; DePoy, D. L.; Drummond,
   J.; Eastman, J. D.; Gal-Yam, A.; Gorbikov, E.; Higgins, D.; Janczak,
   J.; Kaspi, S.; Lee, C. -U.; Mallia, F.; Maury, A.; Monard, L. A. G.;
   Moorhouse, D.; Morgan, N.; Natusch, T.; Ofek, E. O.; Park, B. -G.;
   Pogge, R. W.; Polishook, D.; Santallo, R.; Shporer, A.; Spector, O.;
   Thornley, G.; Yee, J. C.; MiNDSTEp Consortium; Bozza, V.; Browne,
   P.; Dominik, M.; Dreizler, S.; Finet, F.; Glitrup, M.; Grundahl,
   F.; Harpsøe, K.; Hessman, F. V.; Hinse, T. C.; Hundertmark, M.;
   Jørgensen, U. G.; Liebig, C.; Maier, G.; Mancini, L.; Mathiasen,
   M.; Rahvar, S.; Ricci, D.; Scarpetta, G.; Southworth, J.; Surdej,
   J.; Zimmer, F.; RoboNet Collaboration; Allan, A.; Bramich, D. M.;
   Snodgrass, C.; Steele, I. A.; Street, R. A.
Bibcode: 2011A&A...529A.102B
Altcode: 2011arXiv1102.0558B
  <BR /> Aims: We report the discovery of a planet with a high
  planet-to-star mass ratio in the microlensing event MOA-2009-BLG-387,
  which exhibited pronounced deviations over a 12-day interval, one
  of the longest for any planetary event. The host is an M dwarf,
  with a mass in the range 0.07 M<SUB>⊙</SUB> &lt; M<SUB>host</SUB>
  &lt; 0.49 M<SUB>⊙</SUB> at 90% confidence. The planet-star mass
  ratio q = 0.0132 ± 0.003 has been measured extremely well, so at
  the best-estimated host mass, the planet mass is m<SUB>p</SUB> = 2.6
  Jupiter masses for the median host mass, M = 0.19 M<SUB>⊙</SUB>. <BR
  /> Methods: The host mass is determined from two "higher order"
  microlensing parameters. One of these, the angular Einstein radius
  θ<SUB>E</SUB> = 0.31 ± 0.03 mas has been accurately measured,
  but the other (the microlens parallax π<SUB>E</SUB>, which is
  due to the Earth's orbital motion) is highly degenerate with the
  orbital motion of the planet. We statistically resolve the degeneracy
  between Earth and planet orbital effects by imposing priors from a
  Galactic model that specifies the positions and velocities of lenses
  and sources and a Kepler model of orbits. <BR /> Results: The 90%
  confidence intervals for the distance, semi-major axis, and period
  of the planet are 3.5 kpc &lt; D<SUB>L</SUB> &lt; 7.9 kpc, 1.1 AU
  &lt; a &lt; 2.7 AU, and 3.8 yr &lt; P &lt; 7.6 yr, respectively. <P
  />Photometric data is only available in electronic form at the CDS
  via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/529/A102">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/529/A102</A>

Title: XMM-Newton observations of the X-ray soft polar QS Telescopii
Authors: Traulsen, I.; Reinsch, K.; Schwope, A. D.; Burwitz, V.;
   Dreizler, S.; Schwarz, R.; Walter, F. M.
Bibcode: 2011A&A...529A.116T
Altcode: 2011arXiv1103.4575T
  Context. On the basis of XMM-Newton observations, we investigate
  the energy balance of selected magnetic cataclysmic variables,
  which have shown an extreme soft-to-hard X-ray flux ratio in the
  ROSAT All-Sky Survey. <BR /> Aims: We intend to establish the X-ray
  properties of the system components, their flux contributions, and the
  accretion geometry of the X-ray soft polar QS Tel. In the context of
  high-resolution X-ray analyses of magnetic cataclysmic variables, this
  study will contribute to better understanding the accretion processes
  on magnetic white dwarfs. <BR /> Methods: During an intermediate high
  state of accretion of QS Tel, we have obtained 20 ks of XMM-Newton
  data, corresponding to more than two orbital periods, accompanied by
  simultaneous optical photometry and phase-resolved spectroscopy. We
  analyze the multi-wavelength spectra and light curves and compare
  them to former high- and low-state observations. <BR /> Results:
  Soft emission at energies below 2 keV dominates the X-ray light
  curves. The complex double-peaked maxima are disrupted by a sharp
  dip in the very soft energy range (0.1-0.5 keV), where the count rate
  abruptly drops to zero. The EPIC spectra are described by a minimally
  absorbed black body at 20 eV and two partially absorbed mekal plasma
  models with temperatures around 0.2 and 3 keV. The black-body-like
  component arises from one mainly active, soft X-ray bright accretion
  region nearly facing the mass donor. Parts of the plasma emission
  might be attributed to the second, virtually inactive pole. High
  soft-to-hard X-ray flux ratios and hardness ratios demonstrate that the
  high-energy emission of QS Tel is substantially dominated by its X-ray
  soft component. <P />Based on observations obtained with XMM-Newton,
  an ESA science mission with instruments and contributions directly
  funded by ESA Member States and NASA.

Title: VizieR Online Data Catalog: Hot HB stars in ω Cen (Moehler+,
    2011)
Authors: Moehler, S.; Dreizler, S.; Lanz, T.; Bono, G.; Sweigart,
   A. V.; Calamida, A.; Nonino, M.
Bibcode: 2011yCat..35260136M
Altcode: 2011yCat..35269136M
  Moderately high resolution spectra of hot HB stars in the globular
  cluster omega Cen were analysed for radial velocity variations,
  atmospheric parameters, and abundances using LTE and non-LTE model
  atmospheres. <P />The spectroscopic data were obtained in 2005 (4
  observations) and in 2006 (5 observations) in Service Mode using the
  MEDUSA mode of the multi-object fiber spectrograph FLAMES + GIRAFFE on
  the UT2 Telescope of the VLT. We used the low spectroscopic resolution
  mode with the spectral range 3964Å-4567Å (LR2, R=6400) and observed
  spectra for a total of 109 blue hook and canonical blue HB/EHB star
  candidates (see Table 1) and for 17 sky background positions. Each
  observation had an exposure time of 2550s to keep the total execution
  time of the observing block shorter than one hour. <P />(3 data files).

Title: Flux and color variations of the quadruply imaged quasar
    HE 0435-1223
Authors: Ricci, D.; Poels, J.; Elyiv, A.; Finet, F.; Sprimont, P. G.;
   Anguita, T.; Bozza, V.; Browne, P.; Burgdorf, M.; Calchi Novati, S.;
   Dominik, M.; Dreizler, S.; Glitrup, M.; Grundahl, F.; Harpsøe, K.;
   Hessman, F.; Hinse, T. C.; Hornstrup, A.; Hundertmark, M.; Jørgensen,
   U. G.; Liebig, C.; Maier, G.; Mancini, L.; Masi, G.; Mathiasen, M.;
   Rahvar, S.; Scarpetta, G.; Skottfelt, J.; Snodgrass, C.; Southworth,
   J.; Teuber, J.; Thöne, C. C.; Wambsganß, J.; Zimmer, F.; Zub, M.;
   Surdej, J.
Bibcode: 2011A&A...528A..42R
Altcode: 2011arXiv1101.3664R
  <BR /> Aims: We present VRi photometric observations of the quadruply
  imaged quasar<ASTROBJ>HE0435-1223</ASTROBJ>, carried out with the
  Danish 1.54 m telescope at the La Silla Observatory. Our aim was to
  monitor and study the magnitudes and colors of each lensed component
  as a function of time. <BR /> Methods: We monitored the object during
  two seasons (2008 and 2009) in the VRi spectral bands, and reduced the
  data with two independent techniques: difference imaging and point
  spread function (PSF) fitting. <BR /> Results: Between these two
  seasons, our results show an evident decrease in flux by ≈ 0.2-0.4
  magnitudes of the four lensed components in the three filters. We also
  found a significant increase ( ≈ 0.05-0.015) in their V - R and R -
  i color indices. <BR /> Conclusions: These flux and color variations
  are very likely caused by intrinsic variations of the quasar between
  the observed epochs. Microlensing effects probably also affect
  the brightest "A" lensed component. <P />Based on data collected
  by MiNDSTEp with the Danish 1.54 m telescope at the ESO La Silla
  Observatory. Tables 5-7 are only available in electronic form at the
  CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/528/A42">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/528/A42</A>

Title: VizieR Online Data Catalog: MOA-2007-BLG-387Lb light curve
    I band (Batista+, 2011)
Authors: Batista, V.; Gould, A.; Dieters, S.; Dong, Subo; Bond, I.;
   Beaulieu, J. P.; Maoz, D.; Monard, B.; Christie, G. W.; McCormick,
   J.; Albrow, M. D.; Horne, K.; Tsapras, Y.; Burgdorf, M. J.; Calchi
   Novati, S.; Skottfelt, J.; Caldwell, J.; Kozlowski, S.; Kubas, D.;
   Gaudi, B. S.; Han, C.; Bennett1, D. P.; An, J.; Abe, F.; Botzler,
   C. S.; Douchin, D.; Freeman, M.; Fukui, A.; Furusawa, K.; Hearnshaw,
   J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.; Kilmartin, P. M.; Korpela, A.;
   Lin, W.; Ling, C. H.; Makita, S.; Masuda, K.; Matsubara, Y.; Miyake,
   N.; Muraki, Y.; Nagaya, M.; Nishimoto, K.; Ohnishi, K.; Okumura, T.;
   Perrott, Y. C.; Rattenbury, N.; Saito, To.; Sullivan, D. J.; Sumi,
   T.; Sweatman, W. L.; Tristram, P. J.; von Seggern, E.; Yock P. C. M.;
   MOA Collaboration; Brillant, S.; Calitz, J. J.; Cassan, A.; Cole,
   A.; Cook, K.; Coutures, C.; Dominis Prester, D.; Donatowicz, J.;
   Greenhill, J.; Hoffman, M.; Jablonski, F.; Kane, S. R.; Kains, N.;
   Marquette, J. -B.; Martin, R.; Martioli, E.; Meintjes, P.; Menzies,
   J.; Pedretti, E.; Pollard, K.; Sahu, K. C.; Vinter, C.; Wambsganss,
   J.; Watson, R.; Williams, A.; Zub, M.; PLANET Collaboration; Allen,
   W.; Bolt, G.; Bos, M.; DePoy, D. L.; Drummond, J.; Eastman, J. D.;
   Gal-Yam, A.; Gorbikov, E.; Higgins, D.; Janczak, J.; Kaspi, S.; Lee,
   C. -U.; Mallia, F.; Maury, A.; Monard, L. A. G.; Moorhouse, D.; Morgan,
   N.; Natusch, T.; Ofek, E. O.; Park, B. -G.; Pogge, R. W.; Polishook,
   D.; Santallo, R.; Shporer, A.; Spector, O.; Thornley, G.; Yee, J. C.;
   μ Collaboration; Bozza, V.; Browne, P.; Dominik, M.; Dreizler, S.;
   Finet, F.; Glitrup, M.; Grundah, F.; Harpsoe, K.; Hessman, F. V.;
   Hinse, T. C.; Hundertmark, M.; Jorgensen, U. G.; Liebig, C.; Maier,
   G.; Mancini, L.; Mathiasen, M.; Rahvar, S.; Ricci, D.; Scarpetta,
   G.; Southworth, J.; Surdej, J.; Zimmer, F.
Bibcode: 2011yCat..35290102B
Altcode: 2011yCat..35299102B
  The RoboNet collaboration also followed the event with their three
  2m robotic telescopes : the Faulkes Telescopes The microlensing event
  MOA-2009-BLG-387 was alerted North (FTN) and South (FTS) in Hawaii and
  Australia by the MOA collaboration (Microlensing Observations in (Siding
  Springs Observatory) respectively, and the Liverpool Astrophysics)
  on 24 July 2009 at 15:08 UT, HJD'=HJD-24500000=5037.13, a few days
  before the first caustic entry. Many observatories obtained data of
  the event. The celestial coordinates of the event are RA=17:53:50.79
  and DE=-33:59:25 (J2000.0) corresponding to Galactic coordinates:
  l=+356.56, b=-4.097. <P />(1 data file).

Title: The Planets around the post-Common Envelope Binary NN Serpentis
Authors: Hessman, Frederic V.; Beuermann, Klaus; Dreizler, Stefan;
   Marsh, Tom R.; Parsons, Steven G.; Copperwheat, Chris M.; Winget,
   Don E.; Miller, George F.; Hermes, James J.; Schreiber, Matthias R.;
   Kley, Wilhelm; Dhillon, Vik S.; Littlefair, Stuart P.
Bibcode: 2011AIPC.1331..281H
Altcode: 2011arXiv1102.0508H
  We have detected 2 circumbinary planets around the close binary system
  NN Serpentis using the orbital time delay effect measured via the sharp
  eclipses of the white dwarf primary. The present pre-cataclysmic binary
  was formed when the original ~2 M<SUB>solar</SUB> primary expanded into
  a red giant, causing the secondary star to drop from its original orbit
  at a separation of about 1.4 A.U. down to its current separation at
  0.0043 A.U. A quasi-adiabatic evolution of the circumbinary planets'
  orbits during the common-envelope phase would have placed them in
  unstable configurations, suggesting that they may have suffered
  significant orbital drag effects and were originally in much larger
  orbits. Alternatively, they may have been created as 2nd-generation
  planets during the last million years from the substantial amount
  of material lost during the creation of the binary, making them the
  youngest planets known. Either solution shows how little we actually
  understand about planetary formation.

Title: A much lower density for the transiting extrasolar planet
    WASP-7
Authors: Southworth, J.; Dominik, M.; Jørgensen, U. G.; Rahvar,
   S.; Snodgrass, C.; Alsubai, K.; Bozza, V.; Browne, P.; Burgdorf, M.;
   Calchi Novati, S.; Dodds, P.; Dreizler, S.; Finet, F.; Gerner, T.;
   Hardis, S.; Harpsøe, K.; Hellier, C.; Hinse, T. C.; Hundertmark, M.;
   Kains, N.; Kerins, E.; Liebig, C.; Mancini, L.; Mathiasen, M.; Penny,
   M. T.; Proft, S.; Ricci, D.; Sahu, K.; Scarpetta, G.; Schäfer, S.;
   Schönebeck, F.; Surdej, J.
Bibcode: 2011A&A...527A...8S
Altcode: 2010arXiv1012.5181S
  We present the first high-precision photometry of the transiting
  extrasolar planetary system WASP-7, obtained using telescope defocussing
  techniques and reaching a scatter of 0.68 mmag per point. We find that
  the transit depth is greater and that the host star is more evolved
  than previously thought. The planet has a significantly larger
  radius (1.330 ± 0.093 R<SUB>Jup</SUB> versus ; R<SUB>Jup</SUB>)
  and much lower density (0.41 ± 0.10 ρ<SUB>Jup</SUB> versus ;
  ρ<SUB>Jup</SUB>) and surface gravity (13.4 ± 2.6 m s<SUP>-2</SUP>
  versus ; m s<SUP>-2</SUP>) than previous measurements showed. Based
  on the revised properties it is no longer an outlier in planetary
  mass-radius and period-gravity diagrams. We also obtain a more precise
  transit ephemeris for the WASP-7 system. <P />Based on data collected
  by MiNDSTEp with the Danish 1.54 m telescope at the ESO La Silla
  Observatory.Lightcurves data is only available in electronic form at the
  CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/527/A8">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/527/A8</A>

Title: A Sub-Saturn Mass Planet, MOA-2009-BLG-319Lb
Authors: Miyake, N.; Sumi, T.; Dong, Subo; Street, R.; Mancini, L.;
   Gould, A.; Bennett, D. P.; Tsapras, Y.; Yee, J. C.; Albrow, M. D.;
   Bond, I. A.; Fouqué, P.; Browne, P.; Han, C.; Snodgrass, C.; Finet,
   F.; Furusawa, K.; Harpsøe, K.; Allen, W.; Hundertmark, M.; Freeman,
   M.; Suzuki, D.; Abe, F.; Botzler, C. S.; Douchin, D.; Fukui, A.;
   Hayashi, F.; Hearnshaw, J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.;
   Kilmartin, P. M.; Korpela, A.; Lin, W.; Ling, C. H.; Makita, S.;
   Masuda, K.; Matsubara, Y.; Muraki, Y.; Nagayama, T.; Nishimoto, K.;
   Ohnishi, K.; Perrott, Y. C.; Rattenbury, N.; Saito, To.; Skuljan, L.;
   Sullivan, D. J.; Sweatman, W. L.; Tristram, P. J.; Wada, K.; Yock,
   P. C. M.; MOA Collaboration; Bolt, G.; Bos, M.; Christie, G. W.; DePoy,
   D. L.; Drummond, J.; Gal-Yam, A.; Gaudi, B. S.; Gorbikov, E.; Higgins,
   D.; Hwang, K. -H.; Janczak, J.; Kaspi, S.; Lee, C. -U.; Koo, J. -R.;
   Kozłowski, S.; Lee, Y.; Mallia, F.; Maury, A.; Maoz, D.; McCormick,
   J.; Monard, L. A. G.; Moorhouse, D.; Muñoz, J. A.; Natusch, T.;
   Ofek, E. O.; Pogge, R. W.; Polishook, D.; Santallo, R.; Shporer, A.;
   Spector, O.; Thornley, G.; μFUN Collaboration; Allan, A.; Bramich,
   D. M.; Horne, K.; Kains, N.; Steele, I.; RoboNet Collaboration; Bozza,
   V.; Burgdorf, M. J.; Calchi Novati, S.; Dominik, M.; Dreizler, S.;
   Glitrup, M.; Hessman, F. V.; Hinse, T. C.; Jørgensen, U. G.; Liebig,
   C.; Maier, G.; Mathiasen, M.; Rahvar, S.; Ricci, D.; Scarpetta, G.;
   Skottfelt, J.; Southworth, J.; Surdej, J.; Wambsganss, J.; Zimmer,
   F.; MiNDSTEp Consortium; Batista, V.; Beaulieu, J. P.; Brillant,
   S.; Cassan, A.; Cole, A.; Corrales, E.; Coutures, Ch.; Dieters, S.;
   Greenhill, J.; Kubas, D.; Menzies, J.; PLANET Collaboration
Bibcode: 2011ApJ...728..120M
Altcode: 2010arXiv1010.1809M
  We report the gravitational microlensing discovery of a sub-Saturn
  mass planet, MOA-2009-BLG-319Lb, orbiting a K- or M-dwarf star in the
  inner Galactic disk or Galactic bulge. The high-cadence observations
  of the MOA-II survey discovered this microlensing event and enabled
  its identification as a high-magnification event approximately 24
  hr prior to peak magnification. As a result, the planetary signal at
  the peak of this light curve was observed by 20 different telescopes,
  which is the largest number of telescopes to contribute to a planetary
  discovery to date. The microlensing model for this event indicates a
  planet-star mass ratio of q = (3.95 ± 0.02) × 10<SUP>-4</SUP> and a
  separation of d = 0.97537 ± 0.00007 in units of the Einstein radius. A
  Bayesian analysis based on the measured Einstein radius crossing
  time, t <SUB>E</SUB>, and angular Einstein radius, θ<SUB>E</SUB>,
  along with a standard Galactic model indicates a host star mass of M
  <SUB>L</SUB> = 0.38<SUP>+0.34</SUP> <SUB>-0.18</SUB> M <SUB>sun</SUB>
  and a planet mass of M <SUB>p</SUB> = 50<SUP>+44</SUP> <SUB>-24</SUB>
  M <SUB>⊕</SUB>, which is half the mass of Saturn. This analysis
  also yields a planet-star three-dimensional separation of a =
  2.4<SUP>+1.2</SUP> <SUB>-0.6</SUB> AU and a distance to the planetary
  system of D <SUB>L</SUB> = 6.1<SUP>+1.1</SUP> <SUB>-1.2</SUB> kpc. This
  separation is ~2 times the distance of the snow line, a separation
  similar to most of the other planets discovered by microlensing.

Title: The hot horizontal-branch stars in ω Centauri
Authors: Moehler, S.; Dreizler, S.; Lanz, T.; Bono, G.; Sweigart,
   A. V.; Calamida, A.; Nonino, M.
Bibcode: 2011A&A...526A.136M
Altcode: 2010arXiv1009.3191M
  Context. UV observations of some massive globular clusters have revealed
  a significant population of stars hotter and fainter than the hot end of
  the horizontal branch (HB), the so-called blue hook stars. This feature
  might be explained either by the late hot flasher scenario where stars
  experience the helium flash while on the white dwarf cooling curve
  or by the progeny of the helium-enriched sub-population postulated to
  exist in some clusters. Previous spectroscopic analyses of blue hook
  stars in ω Cen and NGC 2808 support the late hot flasher scenario,
  but the stars contain much less helium than expected and the predicted
  C and N enrichment cannot be verified. <BR /> Aims: We compare the
  observed effective temperatures, surface gravities, helium abundances,
  and carbon line strengths (where detectable) of our targets stars
  with the predictions of the two aforementioned scenarios. <BR />
  Methods: Moderately high resolution spectra of hot HB stars in the
  globular cluster ω Cen were analysed for radial velocity variations,
  atmospheric parameters, and abundances using LTE and non-LTE model
  atmospheres. <BR /> Results: We find no evidence of close binaries
  among our target stars. All stars below 30 000 K are helium-poor and
  very similar to HB stars observed in that temperature range in other
  globular clusters. In the temperature range 30 000 K to 50 000 K,
  we find that 28% of our stars are helium-poor ({log{n_He}/{n_H}} &lt;
  -1.6), while 72% have roughly solar or super-solar helium abundance
  ({log{n_He}/{n_H}} ≥ -1.5). We also find that carbon enrichment
  is strongly correlated with helium enrichment, with a maximum carbon
  enrichment of 3% by mass. <BR /> Conclusions: A strong carbon enrichment
  in tandem with helium enrichment is predicted by the late hot flasher
  scenario, but not by the helium-enrichment scenario. We conclude that
  the helium-rich HB stars in ω Cen cannot be explained solely by the
  helium-enrichment scenario invoked to explain the blue main sequence. <P
  />Based on observations with the ESO Very Large Telescope at Paranal
  Observatory, Chile (proposal IDs 075.D-0280(A) and 077.D-0021(A)).

Title: The giant planet orbiting the cataclysmic binary DP Leonis
Authors: Beuermann, K.; Buhlmann, J.; Diese, J.; Dreizler, S.; Hessman,
   F. V.; Husser, T. -O.; Miller, G. F.; Nickol, N.; Pons, R.; Ruhr,
   D.; Schmülling, H.; Schwope, A. D.; Sorge, T.; Ulrichs, L.; Winget,
   D. E.; Winget, K. I.
Bibcode: 2011A&A...526A..53B
Altcode: 2010arXiv1011.3905B
  Planets orbiting post-common envelope binaries provide fundamental
  information on planet formation and evolution, especially for the
  yet nearly unexplored class of circumbinary planets. We searched for
  such planets in DP Leo, an eclipsing short-period binary, which shows
  long-term eclipse-time variations. Using published, reanalysed, and
  new mid-eclipse times of the white dwarf in DP Leo, obtained between
  1979 and 2010, we find agreement with the light-travel-time effect
  produced by a third body in an elliptical orbit. In particular, the
  measured binary period in 2009/2010 and the implied radial velocity
  coincide with the values predicted for the motion of the binary and
  the third body around the common center of mass. The orbital period,
  semi-major axis, and eccentricity of the third body are P<SUB>c</SUB>
  = 28.0 ± 2.0 yrs, a<SUB>c</SUB> = 8.2 ± 0.4 AU, and e<SUB>c</SUB>
  = 0.39 ± 0.13. Its mass of sin i_ c M_c = 6.1 ± 0.5 M<SUB>Jup</SUB>
  qualifies it as a giant planet. It formed either as a first generation
  object in a protoplanetary disk around the original binary or as a
  second generation object in a disk formed in the common envelope shed
  by the progenitor of the white dwarf. Even a third generation origin
  in matter lost from the present accreting binary can not be entirely
  excluded. We searched for, but found no evidence for a fourth body.

Title: Giant Transiting Planets Observations with LAIWO
Authors: Nikolov, N.; Moyano, M.; Henning, T.; Dreizler, S.; Mundt, R.
Bibcode: 2011EPJWC..1106004N
Altcode:
  We present preliminary single field results on a search for transiting
  extrasolar planets with the LAIWO wide field optical CCD camera,
  attached to the 1-m telescope at the Wise Observatory. With a 3 min
  integration time, the system achieved a few mmag precision for the
  brightest stars in a field of view of one square degree. We detect
  several periodic variables and a few transit-like events. The promising
  candidates will be followed-up in the near future.

Title: VizieR Online Data Catalog: Transiting planetary system WASP-7
    (Southworth+, 2011)
Authors: Southworth, J.; Dominik, M.; Jorgensen, U. G.; Rahvar, S.;
   Snodgrass, C.; Alsubai, K.; Bozza, V.; Browne, P.; Burgdorf, M.;
   Calchi Novati, S.; Dodds, P.; Dreizler, S.; Finet, F.; Gerner, T.;
   Hardis, S.; Harpsoe, K.; Hellier, C.; Hinse, T. C.; Hundertmark, M.;
   Kains, N.; Kerins, E.; Liebig, C.; Mancini, L.; Mathiasen, M.; Penny,
   M. T.; Proft, S.; Ricci, D.; Scarpetta, G.; Schaefer, S.; Schoenebeck,
   F.; Surdej, J.
Bibcode: 2011yCat..35270008S
Altcode: 2011yCat..35279008S
  A light curve of one transit of the extrasolar planetary system
  WASP-7 is presented. The data were obtained using the Danish 1.5m
  telescope and DFOSC camera at ESO La Silla in 2010, with substantial
  telescope defocussing in order to improve the photometric precision
  of the observations. A Johnson I filter and exposure times of 60s were
  used. <P />(1 data file).

Title: VizieR Online Data Catalog: VRi light curves of the lensed
    QSO HE 0435-1223 (Ricci+, 2011)
Authors: Ricci, D.; Poels, J.; Elyiv, A.; Finet, F.; Sprimont, P. G.;
   Anguita, T.; Bozza, V.; Browne, P.; Burgdorf, M.; Calchi Novati,
   S.; Dominik, M.; Dreizler, S.; Glitrup, M.; Grundahl, F.; Harps, K.;
   Hessman, F.; Hinse, T. C.; Hornstrup, A.; Hundertmark, M.; Jorgensen,
   U. G.; Liebig, C.; Maier, G.; Mancini, L.; Masi, G.; Mathiasen, M.;
   Rahvar, S.; Scarpetta, G.; Skottfelt, J.; Snodgrass, C.; Southworth,
   J.; Teuber, J.; Thone, C. C.; Wambsganss, J.; Zimmer, F.; Zub, M.;
   Surdej, J.
Bibcode: 2011yCat..35280042R
Altcode: 2011yCat..35289042R
  Tables contain the light curves of the 4 components of the quasar,
  in the V, R, and i bands. <P />(3 data files).

Title: Asteroseismology of solar-type stars with Kepler:
    III. Ground-based data
Authors: Molenda-Żakowicz, J.; Bruntt, H.; Sousa, S.; Frasca,
   A.; Biazzo, K.; Huber, D.; Ireland, M.; Bedding, T.; Stello, D.;
   Uytterhoeven, K.; Dreizler, S.; De Cat, P.; Briquet, M.; Catanzaro,
   G.; Karoff, C.; Frandsen, S.; Spezzi, L.
Bibcode: 2010AN....331..981M
Altcode: 2010arXiv1005.0986M
  We report on the ground-based follow-up program of spectroscopic and
  photometric observations of solar-like asteroseismic targets for
  the Kepler space mission. These stars constitute a large group of
  more than a thousand objects which are the subject of an intensive
  study by the Kepler Asteroseismic Science Consortium Working Group 1
  (KASC WG-1). In the current work we will discuss the methods we use
  to determine the fundamental stellar atmospheric parameters using
  high-quality stellar spectra. These provide essential constraints
  for the asteroseismic modelling and make it possible to verify the
  parameters in the Kepler Input Catalogue (KIC).

Title: ERRATUM: "Physical Properties of the 0.94 Day Period Transiting
    Planetary System WASP-18" <A href="/abs/2009ApJ...707..167S">(2009,
    ApJ, 707, 167)</A>
Authors: Southworth, John; Hinse, T. C.; Dominik, M.; Glitrup, M.;
   Jørgensen, U. G.; Liebig, C.; Mathiasen, M.; Anderson, D. R.; Bozza,
   V.; Browne, P.; Burgdorf, M.; Calchi Novati, S.; Dreizler, S.; Finet,
   F.; Harpsøe, K.; Hessman, F.; Hundertmark, M.; Maier, G.; Mancini,
   L.; Maxted, P. F. L.; Rahvar, S.; Ricci, D.; Scarpetta, G.; Skottfelt,
   J.; Snodgrass, C.; Surdej, J.; Zimmer, F.
Bibcode: 2010ApJ...723.1829S
Altcode:
  No abstract at ADS

Title: OGLE-2009-BLG-092/MOA-2009-BLG-137: A Dramatic Repeating
    Event with the Second Perturbation Predicted by Real-time Analysis
Authors: Ryu, Y. -H.; Han, C.; Hwang, K. -H.; Street, R.; Udalski,
   A.; Sumi, T.; Fukui, A.; Beaulieu, J. -P.; Gould, A.; Dominik, M.;
   Abe, F.; Bennett, D. P.; Bond, I. A.; Botzler, C. S.; Furusawa, K.;
   Hayashi, F.; Hearnshaw, J. B.; Hosaka, S.; Itow, Y.; Kamiya, K.;
   Kilmartin, P. M.; Korpela, A.; Lin, W.; Ling, C. H.; Makita, S.;
   Masuda, K.; Matsubara, Y.; Miyake, N.; Muraki, Y.; Nishimoto, K.;
   Ohnishi, K.; Perrott, Y. C.; Rattenbury, N.; Saito, To.; Skuljan, L.;
   Sullivan, D. J.; Suzuki, D.; Sweatman, W. L.; Tristram, P. J.; Wada,
   K.; Yock, P. C. M.; MOA Collaboration; Szymański, M. K.; Kubiak,
   M.; Pietrzyński, G.; Poleski, R.; Soszyński, I.; Szewczyk, O.;
   Wyrzykowski, Ł.; Ulaczyk, K.; OGLE Collaboration; Bos, M.; Christie,
   G. W.; Depoy, D. L.; Gal-Yam, A.; Gaudi, B. S.; Kaspi, S.; Lee,
   C. -U.; Maoz, D.; McCormick, J.; Monard, B.; Moorhouse, D.; Pogge,
   R. W.; Polishook, D.; Shvartzvald, Y.; Shporer, A.; Thornley, G.; Yee,
   J. C.; μFUN Collaboration; Albrow, M. D.; Batista, V.; Brillant,
   S.; Cassan, A.; Cole, A.; Corrales, E.; Coutures, Ch.; Dieters, S.;
   Fouqué, P.; Greenhill, J.; Menzies, J.; PLANET Collaboration; Allan,
   A.; Bramich, D. M.; Browne, P.; Horne, K.; Kains, N.; Snodgrass, C.;
   Steele, I.; Tsapras, Y.; RoboNet Collaboration; Bozza, V.; Burgdorf,
   M. J.; Calchi Novati, S.; Dreizler, S.; Finet, F.; Glitrup, M.;
   Grundahl, F.; Harpsøe, K.; Hessman, F. V.; Hinse, T. C.; Hundertmark,
   M.; Jørgensen, U. G.; Liebig, C.; Maier, G.; Mancini, L.; Mathiasen,
   M.; Rahvar, S.; Ricci, D.; Scarpetta, G.; Skottfelt, J.; Surdej, J.;
   Southworth, J.; Wambsganss, J.; Zimmer, F.; MiNDSTEp Collaboration
Bibcode: 2010ApJ...723...81R
Altcode: 2010arXiv1009.0338R
  We report the result of the analysis of a dramatic repeating
  gravitational microlensing event OGLE-2009-BLG-092/MOA-2009-BLG-137,
  for which the light curve is characterized by two distinct peaks with
  perturbations near both peaks. We find that the event is produced by
  the passage of the source trajectory over the central perturbation
  regions associated with the individual components of a wide-separation
  binary. The event is special in the sense that the second perturbation,
  occurring ~100 days after the first, was predicted by the real-time
  analysis conducted after the first peak, demonstrating that real-time
  modeling can be routinely done for binary and planetary events. With
  the data obtained from follow-up observations covering the second peak,
  we are able to uniquely determine the physical parameters of the lens
  system. We find that the event occurred on a bulge clump giant and it
  was produced by a binary lens composed of a K- and M-type main-sequence
  stars. The estimated masses of the binary components are M <SUB>1</SUB>
  = 0.69 ± 0.11 M <SUB>sun</SUB> and M <SUB>2</SUB> = 0.36 ± 0.06 M
  <SUB>sun</SUB>, respectively, and they are separated in projection by
  r <SUB>bottom</SUB> = 10.9 ± 1.3 AU. The measured distance to the
  lens is D <SUB>L</SUB> = 5.6 ± 0.7 kpc. We also detect the orbital
  motion of the lens system.

Title: A Precise Asteroseismic Age and Radius for the Evolved Sun-like
    Star KIC 11026764
Authors: Metcalfe, T. S.; Monteiro, M. J. P. F. G.; Thompson, M. J.;
   Molenda-Żakowicz, J.; Appourchaux, T.; Chaplin, W. J.; Doǧan, G.;
   Eggenberger, P.; Bedding, T. R.; Bruntt, H.; Creevey, O. L.; Quirion,
   P. -O.; Stello, D.; Bonanno, A.; Silva Aguirre, V.; Basu, S.; Esch,
   L.; Gai, N.; Di Mauro, M. P.; Kosovichev, A. G.; Kitiashvili, I. N.;
   Suárez, J. C.; Moya, A.; Piau, L.; García, R. A.; Marques, J. P.;
   Frasca, A.; Biazzo, K.; Sousa, S. G.; Dreizler, S.; Bazot, M.; Karoff,
   C.; Frandsen, S.; Wilson, P. A.; Brown, T. M.; Christensen-Dalsgaard,
   J.; Gilliland, R. L.; Kjeldsen, H.; Campante, T. L.; Fletcher, S. T.;
   Handberg, R.; Régulo, C.; Salabert, D.; Schou, J.; Verner, G. A.;
   Ballot, J.; Broomhall, A. -M.; Elsworth, Y.; Hekker, S.; Huber, D.;
   Mathur, S.; New, R.; Roxburgh, I. W.; Sato, K. H.; White, T. R.;
   Borucki, W. J.; Koch, D. G.; Jenkins, J. M.
Bibcode: 2010ApJ...723.1583M
Altcode: 2010arXiv1010.4329M
  The primary science goal of the Kepler Mission is to provide
  a census of exoplanets in the solar neighborhood, including the
  identification and characterization of habitable Earth-like planets. The
  asteroseismic capabilities of the mission are being used to determine
  precise radii and ages for the target stars from their solar-like
  oscillations. Chaplin et al. published observations of three bright
  G-type stars, which were monitored during the first 33.5 days of science
  operations. One of these stars, the subgiant KIC 11026764, exhibits a
  characteristic pattern of oscillation frequencies suggesting that it
  has evolved significantly. We have derived asteroseismic estimates of
  the properties of KIC 11026764 from Kepler photometry combined with
  ground-based spectroscopic data. We present the results of detailed
  modeling for this star, employing a variety of independent codes and
  analyses that attempt to match the asteroseismic and spectroscopic
  constraints simultaneously. We determine both the radius and the age
  of KIC 11026764 with a precision near 1%, and an accuracy near 2%
  for the radius and 15% for the age. Continued observations of this
  star promise to reveal additional oscillation frequencies that will
  further improve the determination of its fundamental properties.

Title: Evidence for planets orbiting the post-common envelope binary
    NN Serpentis
Authors: Dreizler, S.; Beuermann, K.; Hessman, F. V.; Marsh, T. R.;
   Parsons, S. G.; Dhillon, V. S.; Schreiber, M. R.; Kley, W.; Miller,
   G. F.
Bibcode: 2010AIPC.1273..450D
Altcode:
  From published and new mid-eclipse times obtained between 1988 and 2010
  we find long-term eclipse time variations in the post-common envelope
  eclipsing binary NN Ser. We find strong evidence for two circum-binary
  planets in this system with orbital periods of P<SUB>c</SUB> = 15.5
  and P<SUB>d</SUB> = 7.7 yrs, small eccentricities of e<SUB>c</SUB>~0
  and e<SUB>d</SUB>~0.2 and lower mass limits of M<SUB>c</SUB>
  sin i<SUB>c</SUB> = 6.9 and M<SUB>c</SUB> sin i<SUB>c</SUB> = 2.2
  M<SUB>Jup</SUB>. The periods suggest that the planets are locked in
  a 2:1 resonance. A second solution with a 5:2 resonance and slightly
  modified planetary parameters results in a nearly equal reduced
  χ<SUP>2</SUP>. The progenitor system is estimated to consists of a ~2
  M<SUB>solar</SUB> primary and the present M dwarf secondary at ~1.5 AU
  distance. The first generation formation of planets and their survival
  in the later evolutionary stages or the second generation formation
  in the common envelope shed new light on planet formation and evolution.

Title: Pathways towards Neptune-mass Planets around Very Low-mass
    Stars
Authors: Dreizler, S.; Bean, J.; Seifahrt, A.; Hartman, H.; Nilsson,
   H.; Wiedemann, G.; Reiners, A.; Henry, T. J.
Bibcode: 2010ASPC..430..127D
Altcode:
  Radial velocities measured from near-infrared spectra are a potentially
  powerful tool to search for planets around low-mass stars. The radial
  velocity precision routinely obtained in the visible can, however,
  not be achieved in the NIR with existing techniques. In this paper,
  we describe a method for measuring high-precision radial velocities
  of a sample of the lowest-mass M dwarfs using CRIRES on the VLT. Our
  project makes use of a gas cell filled with ammonia to calibrate the
  instrument response similar to the iodine cell technique that has
  been used so successfully in the visible. Tests of the method based
  on the analysis of hundreds of spectra obtained for late M dwarfs
  over six months demonstrate that precisions of ∼5 m s<SUP>-1</SUP>
  are obtainable over long timescales, and precisions better than 3 m
  s<SUP>-1</SUP> can be obtained over timescales up to a week. This
  allows to search for low-mass planets, i.e., Neptune-mass or even
  Super-Earth planets around very low-mass stars or sub-stellar objects.

Title: Two planets orbiting the recently formed post-common envelope
    binary NN Serpentis
Authors: Beuermann, K.; Hessman, F. V.; Dreizler, S.; Marsh, T. R.;
   Parsons, S. G.; Winget, D. E.; Miller, G. F.; Schreiber, M. R.; Kley,
   W.; Dhillon, V. S.; Littlefair, S. P.; Copperwheat, C. M.; Hermes,
   J. J.
Bibcode: 2010A&A...521L..60B
Altcode: 2010arXiv1010.3608B
  Planets orbiting post-common envelope binaries provide fundamental
  information on planet formation and evolution. We searched for such
  planets in NN Ser ab, an eclipsing short-period binary that shows
  long-term eclipse time variations. Using published, reanalysed, and
  new mid-eclipse times of NN Ser ab obtained between 1988 and 2010, we
  find excellent agreement with the light-travel-time effect produced
  by two additional bodies superposed on the linear ephemeris of the
  binary. Our multi-parameter fits accompanied by N-body simulations
  yield a best fit for the objects NN Ser (ab)c and d locked in the 2:1
  mean motion resonance, with orbital periods P<SUB>c</SUB> ≃ 15.5 yrs
  and P<SUB>d</SUB> ≃ 7.7 yrs, masses M<SUB>c</SUB> sin i<SUB>c</SUB>
  ≃ 6.9 M<SUB>Jup</SUB> and M<SUB>d</SUB> sin i<SUB>d</SUB> ≃ 2.2
  M<SUB>Jup</SUB> and eccentricities e<SUB>c</SUB> ≃ 0 and e<SUB>d</SUB>
  ≃ 0.20. A secondary χ<SUP>2</SUP> minimum corresponds to an
  alternative solution with a period ratio of 5:2. We estimate that the
  progenitor binary consisted of an A star with ~2 M_⊙ and the present
  M dwarf secondary at an orbital separation of ~1.5 AU. The survival of
  two planets through the common-envelope phase that created the present
  white dwarf requires fine tuning between the gravitational force
  and the drag force experienced by them in the expanding envelope. The
  alternative is a second-generation origin in a circumbinary disk created
  at the end of this phase. In that case, the planets would be extremely
  young with ages not exceeding the cooling age of the white dwarf of
  10<SUP>6</SUP> yrs. <P />Table 3 is only available in electronic form
  at <A href="http://www.aanda.org">http://www.aanda.org</A>

Title: Ground-based Multisite Observations of Two Transits of
    HD 80606b
Authors: Shporer, A.; Winn, J. N.; Dreizler, S.; Colón, K. D.;
   Wood-Vasey, W. M.; Choi, P. I.; Morley, C.; Moutou, C.; Welsh, W. F.;
   Pollaco, D.; Starkey, D.; Adams, E.; Barros, S. C. C.; Bouchy, F.;
   Cabrera-Lavers, A.; Cerutti, S.; Coban, L.; Costello, K.; Deeg, H.;
   Díaz, R. F.; Esquerdo, G. A.; Fernandez, J.; Fleming, S. W.; Ford,
   E. B.; Fulton, B. J.; Good, M.; Hébrard, G.; Holman, M. J.; Hunt, M.;
   Kadakia, S.; Lander, G.; Lockhart, M.; Mazeh, T.; Morehead, R. C.;
   Nelson, B. E.; Nortmann, L.; Reyes, F.; Roebuck, E.; Rudy, A. R.;
   Ruth, R.; Simpson, E.; Vincent, C.; Weaver, G.; Xie, J. -W.
Bibcode: 2010ApJ...722..880S
Altcode: 2010arXiv1008.4129S
  We present ground-based optical observations of the 2009 September
  and 2010 January transits of HD 80606b. Based on three partial light
  curves of the 2009 September event, we derive a midtransit time of
  T<SUB>c</SUB> [HJD] = 2455099.196 ± 0.026, which is about 1σ away
  from the previously predicted time. We observed the 2010 January event
  from nine different locations, with most phases of the transit being
  observed by at least three different teams. We determine a midtransit
  time of T<SUB>c</SUB> [HJD] = 2455210.6502 ± 0.0064, which is within
  1.3σ of the time derived from a Spitzer observation of the same event.

Title: EXOTIME: searching for planets around pulsating subdwarf
    B stars
Authors: Schuh, Sonja; Silvotti, Roberto; Lutz, Ronny; Loeptien,
   Björn; Green, Elizabeth M.; Østensen, Roy H.; Leccia, Silvio;
   Kim, Seung-Lee; Fontaine, Gilles; Charpinet, Stéphane; Francœur,
   Myriam; Randall, Suzanna; Rodríguez-López, Cristina; Van Grootel,
   Valerie; Odell, Andrew P.; Paparó, Margit; Bognár, Zsófia; Pápics,
   Péter; Nagel, Thorsten; Beeck, Benjamin; Hundertmark, Markus; Stahn,
   Thorsten; Dreizler, Stefan; Hessman, Frederic V.; Dall'Ora, Massimo;
   Mancini, Dario; Cortecchia, Fausto; Benatti, Serena; Claudi, Riccardo;
   Janulis, Rimvydas
Bibcode: 2010Ap&SS.329..231S
Altcode: 2010arXiv1005.3461S; 2010Ap&SS.tmp..130S
  In 2007, a companion with planetary mass was found around
  the pulsating subdwarf B star V391 Pegasi with the timing
  method, indicating that a previously undiscovered population
  of substellar companions to apparently single subdwarf B stars
  might exist. Following this serendipitous discovery, the EXOTIME
  (&lt;ExternalRef&gt; &lt;RefSource&gt;http://www.na.astro.it/
  silvotti/exotime/&lt;/RefSource&gt; &lt;RefTarget
  Address="http://www.na.astro.it/ silvotti/exotime/"
  TargetType="URL"/&gt; &lt;/ExternalRef&gt;) monitoring program has
  been set up to follow the pulsations of a number of selected rapidly
  pulsating subdwarf B stars on time scales of several years with two
  immediate observational goals: <P />(1) <P />determine dot{P} of the
  pulsational periods P

Title: CARMENES: Calar Alto high-resolution search for M dwarfs with
    exo-earths with a near-infrared Echelle spectrograph
Authors: Quirrenbach, A.; Amado, P. J.; Mandel, H.; Caballero, J. A.;
   Mundt, R.; Ribas, I.; Reiners, A.; Abril, M.; Aceituno, J.; Afonso,
   C.; Barrado y Navascues, D.; Bean, J. L.; Béjar, V. J. S.; Becerril,
   S.; Böhm, A.; Cárdenas, M. C.; Claret, A.; Colomé, J.; Costillo,
   L. P.; Dreizler, S.; Fernández, M.; Francisco, X.; Galadí, D.;
   Garrido, R.; González Hernández, J. I.; Guàrdia, J.; Guenther,
   E. W.; Gutiérrez-Soto, F.; Joergens, V.; Hatzes, A. P.; Helmling,
   J.; Henning, T.; Herrero, E.; Kürster, M.; Laun, W.; Lenzen, R.;
   Mall, U.; Martin, E. L.; Martín-Ruiz, S.; Mirabet, E.; Montes, D.;
   Morales, J. C.; Morales Muñoz, R.; Moya, A.; Naranjo, V.; Rabaza,
   O.; Ramón, A.; Rebolo, R.; Reffert, S.; Rodler, F.; Rodríguez, E.;
   Rodríguez Trinidad, A.; Rohloff, R. R.; Sánchez Carrasco, M. A.;
   Schmidt, C.; Seifert, W.; Setiawan, J.; Solano, E.; Stahl, O.; Storz,
   C.; Suárez, J. C.; Thiele, U.; Wagner, K.; Wiedemann, G.; Zapatero
   Osorio, M. R.; del Burgo, C.; Sánchez-Blanco, E.; Xu, W.
Bibcode: 2010SPIE.7735E..13Q
Altcode: 2010SPIE.7735E..37Q
  CARMENES (Calar Alto high-Resolution search for M dwarfs with
  Exo-earths with Near-infrared and optical Echelle Spectrographs)
  is a next-generation instrument to be built for the 3.5m telescope
  at the Calar Alto Observatory by a consortium of Spanish and German
  institutions. Conducting a five-year exoplanet survey targeting ~
  300 M stars with the completed instrument is an integral part of the
  project. The CARMENES instrument consists of two separate spectrographs
  covering the wavelength range from 0.52 to 1.7 μm at a spectral
  resolution of R = 85, 000, fed by fibers from the Cassegrain focus of
  the telescope. The spectrographs are housed in a temperature-stabilized
  environment in vacuum tanks, to enable a 1m/s radial velocity precision
  employing a simultaneous ThAr calibration.

Title: The MUSE second-generation VLT instrument
Authors: Bacon, R.; Accardo, M.; Adjali, L.; Anwand, H.; Bauer, S.;
   Biswas, I.; Blaizot, J.; Boudon, D.; Brau-Nogue, S.; Brinchmann, J.;
   Caillier, P.; Capoani, L.; Carollo, C. M.; Contini, T.; Couderc,
   P.; Daguisé, E.; Deiries, S.; Delabre, B.; Dreizler, S.; Dubois,
   J.; Dupieux, M.; Dupuy, C.; Emsellem, E.; Fechner, T.; Fleischmann,
   A.; François, M.; Gallou, G.; Gharsa, T.; Glindemann, A.; Gojak, D.;
   Guiderdoni, B.; Hansali, G.; Hahn, T.; Jarno, A.; Kelz, A.; Koehler,
   C.; Kosmalski, J.; Laurent, F.; Le Floch, M.; Lilly, S. J.; Lizon,
   J. -L.; Loupias, M.; Manescau, A.; Monstein, C.; Nicklas, H.; Olaya,
   J. -C.; Pares, L.; Pasquini, L.; Pécontal-Rousset, A.; Pelló, R.;
   Petit, C.; Popow, E.; Reiss, R.; Remillieux, A.; Renault, E.; Roth,
   M.; Rupprecht, G.; Serre, D.; Schaye, J.; Soucail, G.; Steinmetz, M.;
   Streicher, O.; Stuik, R.; Valentin, H.,; Vernet, J.; Weilbacher, P.;
   Wisotzki, L.; Yerle, N.
Bibcode: 2010SPIE.7735E..08B
Altcode: 2010SPIE.7735E...7B
  Summary: The Multi Unit Spectroscopic Explorer (MUSE) is a
  second-generation VLT panoramic integral-field spectrograph currently
  in manufacturing, assembly and integration phase. MUSE has a field of
  1x1 arcmin<SUP>2</SUP> sampled at 0.2x0.2 arcsec<SUP>2</SUP> and is
  assisted by the VLT ground layer adaptive optics ESO facility using
  four laser guide stars. The instrument is a large assembly of 24
  identical high performance integral field units, each one composed
  of an advanced image slicer, a spectrograph and a 4kx4k detector. In
  this paper we review the progress of the manufacturing and report the
  performance achieved with the first integral field unit.

Title: X-ray spectroscopy and photometry of the long-period polar
    AI Trianguli with XMM-Newton
Authors: Traulsen, I.; Reinsch, K.; Schwarz, R.; Dreizler, S.;
   Beuermann, K.; Schwope, A. D.; Burwitz, V.
Bibcode: 2010A&A...516A..76T
Altcode: 2010arXiv1004.1629T
  Context. The energy balance of cataclysmic variables with strong
  magnetic fields is a central subject in understanding accretion
  processes on magnetic white dwarfs. With XMM-Newton, we perform a
  spectroscopic and photometric study of soft X-ray selected polars
  during their high states of accretion. <BR /> Aims: On the basis of
  X-ray and optical observations of the magnetic cataclysmic variable
  AI Tri, we derive the properties of the spectral components, their
  flux contributions, and the physical structure of the accretion
  region in soft polars. <BR /> Methods: We use multi-temperature
  approaches in our xspec modeling of the X-ray spectra to describe the
  physical conditions and the structures of the post-shock accretion
  flow and the accretion spot on the white-dwarf surface. In addition,
  we investigate the accretion geometry of the system by completing a
  timing analysis of the photometric data. <BR /> Results: Flaring
  soft X-ray emission from the heated surface of the white dwarf
  dominates the X-ray flux during roughly 70% of the binary cycle. This
  component deviates from a single black body and can be described by
  a superimposition of mildly absorbed black bodies with a Gaussian
  temperature distribution between kT<SUB>bb,low</SUB> := 2 eV and
  kT<SUB>bb,high</SUB> = 43.9<SUP>+3.3</SUP><SUB>-3.2</SUB> eV, and
  {N}_H,ISM = 1.5<SUP>+0.8</SUP><SUB>-0.7</SUB>× 10<SUP>20</SUP>
  cm<SUP>-2</SUP>. In addition, weaker hard X-ray emission is visible
  nearly all the time. The spectrum from the cooling post-shock accretion
  flow is most closely fitted by a combination of thermal plasma
  mekal models with temperature profiles adapted from prior stationary
  two-fluid hydrodynamic calculations. The resulting plasma temperatures
  lie between kT_MEKAL,{low} = 0.8<SUP>+0.4</SUP><SUB>-0.2</SUB>
  keV and kT_MEKAL,{high} = 20.0<SUP>+9.9</SUP><SUB>-6.1</SUB> keV;
  additional intrinsic, partial-covering absorption is on the order of
  N<SUB>H,int</SUB> = 3.3<SUP>+2.5</SUP><SUB>-1.2</SUB>× 10<SUP>23</SUP>
  cm<SUP>-2</SUP>. The soft X-ray light curves show a dip during the
  bright phase, which can be interpreted as self-absorption in the
  accretion stream. Phase-resolved spectral modeling supports the picture
  of one-pole accretion and self-eclipse. One of the optical light curves
  corresponds to an irregular mode of accretion. During a short XMM-Newton
  observation at the same epoch, the X-ray emission of the system is
  clearly dominated by the soft component. <P />Based on observations
  obtained with XMM-Newton, an ESA science mission with instruments and
  contributions directly funded by ESA Member States and NASA.

Title: The CRIRES Search for Planets at the Bottom of the Main
    Sequence
Authors: Bean, J.; Seifahrt, A.; Hartman, H.; Nilsson, H.; Wiedemann,
   G.; Reiners, A.; Dreizler, S.; Henry, T.
Bibcode: 2010Msngr.140...41B
Altcode:
  We present the first results obtained from our ongoing search
  for planets around very low-mass stars and brown dwarfs using
  radial velocities measured with the CRIRES spectrograph on the
  VLT. High-precision radial velocity measurements for a large sample
  of these previously neglected stars are enabled by observing at
  near-infrared wavelengths and using a new type of gas cell that we
  have developed. Unprecedented long-term near-infrared radial velocity
  precisions of ~ 5 ms-1 have been demonstrated using CRIRES with the
  cell. As a first scientific result, data obtained for the very low-mass
  star VB 10 have been used to refute a claimed planet detection based
  on astrometry. These results demonstrate the unique sensitivity of
  our methodology, and confirm its power to detect planets, including
  potentially habitable ones, around the most numerous stars in the
  Galaxy.

Title: Discovery of a nearby young brown dwarf binary candidate
Authors: Reiners, A.; Seifahrt, A.; Dreizler, S.
Bibcode: 2010A&A...513L...9R
Altcode: 2010arXiv1003.1715R
  In near-infrared NaCo observations of the young brown dwarf 2MASS
  J0041353-562112, we discovered a companion a little less than
  a magnitude fainter than the primary. The binary candidate has a
  separation of 143 mas, and the spectral types of the two components
  are M 6.5 and M 9.0. Colors and flux ratios of the components are
  consistent with their locations being at the same distance minimizing
  the probability of the secondary being a background object. The
  brown dwarf is known to exhibit Li absorption constraining the age
  to be younger than ~ 200 Myr, and has been suspected of experiencing
  ongoing accretion, which implies an age as young as ~ 10 Myr. We
  estimate distance and orbital parameters of the binary as a function
  of age. For an age of 10 Myr, the distance to the system is 50 pc,
  the orbital period is 126 yr, and the masses of the components are ~
  30 and ~ 15 M<SUB>Jup</SUB>. The binary brown dwarf fills a so far
  unoccupied region in the parameters mass and age; it is a valuable
  new benchmark object for brown dwarf atmospheric and evolutionary
  models. <P />Emmy Noether Fellow.

Title: The CRIRES Search for Planets Around the Lowest-mass
    Stars. I. High-precision Near-infrared Radial Velocities with an
    Ammonia Gas Cell
Authors: Bean, Jacob L.; Seifahrt, Andreas; Hartman, Henrik; Nilsson,
   Hampus; Wiedemann, Günter; Reiners, Ansgar; Dreizler, Stefan; Henry,
   Todd J.
Bibcode: 2010ApJ...713..410B
Altcode: 2009arXiv0911.3148B
  Radial velocities measured from near-infrared (NIR) spectra are a
  potentially powerful tool to search for planets around cool stars
  and sub-stellar objects. However, no technique currently exists that
  yields NIR radial velocity precision comparable to that routinely
  obtained in the visible. We are carrying out an NIR radial velocity
  planet search program targeting a sample of the lowest-mass M dwarfs
  using the CRIRES instrument on the Very Large Telescope. In this first
  paper in a planned series about the project, we describe a method for
  measuring high-precision relative radial velocities of these stars from
  K-band spectra. The method makes use of a glass cell filled with ammonia
  gas to calibrate the spectrograph response similar to the "iodine cell"
  technique that has been used very successfully in the visible. Stellar
  spectra are obtained through the ammonia cell and modeled as the product
  of a Doppler-shifted template spectrum of the object and a spectrum of
  the cell, convolved with a variable instrumental profile (IP) model. A
  complicating factor is that a significant number of telluric absorption
  lines are present in the spectral regions containing useful stellar and
  ammonia lines. The telluric lines are modeled simultaneously as well
  using spectrum synthesis with a time-resolved model of the atmosphere
  over the observatory. The free parameters in the complete model are
  the wavelength scale of the spectrum, the IP, adjustments to the water
  and methane abundances in the atmospheric model, telluric spectrum
  Doppler shift, and stellar Doppler shift. Tests of the method based
  on the analysis of hundreds of spectra obtained for late-M dwarfs
  over 6 months demonstrate that precisions of ~ 5 m s<SUP>-1</SUP>
  are obtainable over long timescales, and precisions of better than
  3 m s<SUP>-1</SUP> can be obtained over timescales up to a week. The
  obtained precision is comparable to the predicted photon-limited errors,
  but primarily limited over long timescales by the imperfect modeling of
  the telluric lines. <P />Based on observations made with ESO Telescopes
  at the Paranal Observatories under program ID 182.C-0748.

Title: The Asteroseismic Potential of Kepler: First Results for
    Solar-Type Stars
Authors: Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; García,
   R. A.; Houdek, G.; Karoff, C.; Metcalfe, T. S.; Molenda-Żakowicz,
   J.; Monteiro, M. J. P. F. G.; Thompson, M. J.; Brown, T. M.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kjeldsen, H.; Borucki,
   W. J.; Koch, D.; Jenkins, J. M.; Ballot, J.; Basu, S.; Bazot, M.;
   Bedding, T. R.; Benomar, O.; Bonanno, A.; Brandão, I. M.; Bruntt,
   H.; Campante, T. L.; Creevey, O. L.; Di Mauro, M. P.; Doǧan,
   G.; Dreizler, S.; Eggenberger, P.; Esch, L.; Fletcher, S. T.;
   Frandsen, S.; Gai, N.; Gaulme, P.; Handberg, R.; Hekker, S.; Howe,
   R.; Huber, D.; Korzennik, S. G.; Lebrun, J. C.; Leccia, S.; Martic,
   M.; Mathur, S.; Mosser, B.; New, R.; Quirion, P. -O.; Régulo, C.;
   Roxburgh, I. W.; Salabert, D.; Schou, J.; Sousa, S. G.; Stello, D.;
   Verner, G. A.; Arentoft, T.; Barban, C.; Belkacem, K.; Benatti, S.;
   Biazzo, K.; Boumier, P.; Bradley, P. A.; Broomhall, A. -M.; Buzasi,
   D. L.; Claudi, R. U.; Cunha, M. S.; D'Antona, F.; Deheuvels, S.;
   Derekas, A.; García Hernández, A.; Giampapa, M. S.; Goupil, M. J.;
   Gruberbauer, M.; Guzik, J. A.; Hale, S. J.; Ireland, M. J.; Kiss,
   L. L.; Kitiashvili, I. N.; Kolenberg, K.; Korhonen, H.; Kosovichev,
   A. G.; Kupka, F.; Lebreton, Y.; Leroy, B.; Ludwig, H. -G.; Mathis, S.;
   Michel, E.; Miglio, A.; Montalbán, J.; Moya, A.; Noels, A.; Noyes,
   R. W.; Pallé, P. L.; Piau, L.; Preston, H. L.; Roca Cortés, T.;
   Roth, M.; Sato, K. H.; Schmitt, J.; Serenelli, A. M.; Silva Aguirre,
   V.; Stevens, I. R.; Suárez, J. C.; Suran, M. D.; Trampedach, R.;
   Turck-Chièze, S.; Uytterhoeven, K.; Ventura, R.; Wilson, P. A.
Bibcode: 2010ApJ...713L.169C
Altcode: 2010arXiv1001.0506C
  We present preliminary asteroseismic results from Kepler on three G-type
  stars. The observations, made at one-minute cadence during the first
  33.5 days of science operations, reveal high signal-to-noise solar-like
  oscillation spectra in all three stars: about 20 modes of oscillation
  may be clearly distinguished in each star. We discuss the appearance of
  the oscillation spectra, use the frequencies and frequency separations
  to provide first results on the radii, masses, and ages of the stars,
  and comment in the light of these results on prospects for inference
  on other solar-type stars that Kepler will observe.

Title: Discovery of a Red Giant with Solar-like Oscillations in an
    Eclipsing Binary System from Kepler Space-based Photometry
Authors: Hekker, S.; Debosscher, J.; Huber, D.; Hidas, M. G.; De
   Ridder, J.; Aerts, C.; Stello, D.; Bedding, T. R.; Gilliland, R. L.;
   Christensen-Dalsgaard, J.; Brown, T. M.; Kjeldsen, H.; Borucki, W. J.;
   Koch, D.; Jenkins, J. M.; Van Winckel, H.; Beck, P. G.; Blomme,
   J.; Southworth, J.; Pigulski, A.; Chaplin, W. J.; Elsworth, Y. P.;
   Stevens, I. R.; Dreizler, S.; Kurtz, D. W.; Maceroni, C.; Cardini,
   D.; Derekas, A.; Suran, M. D.
Bibcode: 2010ApJ...713L.187H
Altcode: 2010arXiv1001.0399H
  Oscillating stars in binary systems are among the most interesting
  stellar laboratories, as these can provide information on the stellar
  parameters and stellar internal structures. Here we present a red
  giant with solar-like oscillations in an eclipsing binary observed
  with the NASA Kepler satellite. We compute stellar parameters of the
  red giant from spectra and the asteroseismic mass and radius from
  the oscillations. Although only one eclipse has been observed so far,
  we can already determine that the secondary is a main-sequence F star
  in an eccentric orbit with a semi-major axis larger than 0.5 AU and
  orbital period longer than 75 days.

Title: The Proposed Giant Planet Orbiting VB 10 Does Not Exist
Authors: Bean, Jacob L.; Seifahrt, Andreas; Hartman, Henrik; Nilsson,
   Hampus; Reiners, Ansgar; Dreizler, Stefan; Henry, Todd J.; Wiedemann,
   Günter
Bibcode: 2010ApJ...711L..19B
Altcode:
  We present high-precision relative radial velocities of the very low
  mass star VB 10 that were obtained over a time span of 0.61 years as
  part of an ongoing search for planets around stars at the end of the
  main sequence. The radial velocities were measured from high-resolution
  near-infrared spectra obtained using the CRIRES instrument on the
  Very Large Telescope with an ammonia gas cell. The typical internal
  precision of the measurements is 10 m s<SUP>-1</SUP>. These data do
  not exhibit significant variability and are essentially constant at a
  level consistent with the measurement uncertainties. Therefore, we do
  not detect the radial velocity variations of VB 10 expected due to the
  presence of an orbiting giant planet similar to that recently proposed
  by Pravdo &amp; Shaklan based on apparent astrometric perturbations. In
  addition, we do not confirm the ~1 km s<SUP>-1</SUP> radial velocity
  variability of the star tentatively detected by Zapatero Osorio and
  colleagues with lower precision measurements. Our measurements rule out
  planets with M <SUB> p </SUB> &gt; 3 M <SUB>Jup</SUB> and the orbital
  period and inclination suggested by Pravdo &amp; Shaklan at better than
  5σ confidence. We conclude that the planet detection claimed by Pravdo
  &amp; Shaklan is spurious on the basis of this result. Although the
  outcome of this work is a non-detection, it illustrates the potential
  of using ammonia cell radial velocities to detect planets around very
  low mass stars. <P />Based on observations made with ESO Telescopes
  at the Paranal Observatories under program ID 182.C-0748.

Title: Detecting Planets Around Very Low Mass Stars with the Radial
    Velocity Method
Authors: Reiners, A.; Bean, J. L.; Huber, K. F.; Dreizler, S.;
   Seifahrt, A.; Czesla, S.
Bibcode: 2010ApJ...710..432R
Altcode: 2009arXiv0909.0002R
  The detection of planets around very low-mass stars with the radial
  velocity (RV) method is hampered by the fact that these stars are very
  faint at optical wavelengths where the most high-precision spectrometers
  operate. We investigate the precision that can be achieved in RV
  measurements of low mass stars in the near-infrared (NIR) Y-, J-,
  and H-bands, and we compare it to the precision achievable in the
  optical assuming comparable telescope and instrument efficiencies. For
  early-M stars, RV measurements in the NIR offer no or only marginal
  advantage in comparison with optical measurements. Although they emit
  more flux in the NIR, the richness of spectral features in the optical
  outweighs the flux difference. We find that NIR measurement can be
  as precise as optical measurements in stars of spectral type ~M4,
  and from there the NIR gains in precision toward cooler objects. We
  studied potential calibration strategies in the NIR finding that a
  stable spectrograph with a ThAr calibration can offer enough wavelength
  stability for m s<SUP>-1</SUP> precision. Furthermore, we simulate
  the wavelength-dependent influence of activity (cool spots) on RV
  measurements from optical to NIR wavelengths. Our spot simulations
  reveal that the RV jitter does not decrease as dramatically toward
  longer wavelengths as often thought. The jitter strongly depends on
  the details of the spots, i.e., on spot temperature and the spectral
  appearance of the spot. At low temperature contrast (~200 K), the jitter
  shows a decrease toward the NIR up to a factor of 10, but it decreases
  substantially less for larger temperature contrasts. Forthcoming NIR
  spectrographs will allow the search for planets with a particular
  advantage in mid- and late-M stars. Activity will remain an issue,
  but simultaneous observations at optical and NIR wavelengths can
  provide strong constraints on spot properties in active stars.

Title: The CRIRES Search for Planets Around the Lowest-Mass Stars:
    Introduction and First Results
Authors: Bean, Jacob; Seifahrt, A.; Reiners, A.; Dreizler, S.; Hartman,
   H.; Nilsson, H.; Wiedemann, G.; Henry, T.
Bibcode: 2010AAS...21534807B
Altcode: 2010BAAS...42..530B
  We are currently carrying out a search for planets around the
  lowest-mass stars using the CRIRES instrument at the VLT under the
  auspices of an ESO Large Programme. The main purposes of this work are
  to illuminate the correlation between stellar mass and planet formation,
  improve the census of planets, and identify new planets that can be
  followed-up for detailed study. We have developed, and are utilizing
  a new type of gas cell for obtaining high-precision radial velocities
  of late-type stars in the nIR spectral region. Observations in the
  nIR offer the advantages in that the targetted stars are bright enough
  for high-precision spectroscopy, and that the noise contribution from
  stellar activity is significantly reduced. We will give an introduction
  to the survey and present some preliminary results.

Title: The CRIRES Search for Planets Around the Lowest-Mass Stars:
    High-Precision nIR Radial Velocities with a New Gas Cell
Authors: Seifahrt, Andreas; Bean, J.; Hartman, H.; Nilsson, H.;
   Wiedemann, G.; Reiners, A.; Dreizler, S.; Henry, T.
Bibcode: 2010AAS...21542114S
Altcode: 2010BAAS...42..288S
  We are currently carrying out a search for planets around the
  lowest-mass stars using the CRIRES instrument at the VLT under the
  auspices of an ESO Large Programme. The main purposes of this work are
  to illuminate the correlation between stellar mass and planet formation,
  improve the census of planets, and identify new planets that can be
  followed-up for detailed study. We have developed, and are utilizing
  a new type of gas cell for obtaining high-precision radial velocities
  of late-type stars in the nIR spectral region. Observations in the
  nIR offer the advantages in that the targeted stars are bright enough
  for high-precision spectroscopy, and that the noise contribution from
  stellar activity is significantly reduced. We will describe the new
  gas cell and our radial velocity measurement algorithm, and present
  extensive tests of the obtained precision.

Title: The CRIRES Search for Planets Around the Lowest-Mass
    Stars. II. The Proposed Giant Planet Orbiting VB10 Does Not Exist
Authors: Bean, Jacob L.; Seifahrt, Andreas; Hartman, Henrik; Nilsson,
   Hampus; Reiners, Ansgar; Dreizler, Stefan; Henry, Todd J.; Wiedemann,
   Guenter
Bibcode: 2009arXiv0912.0003B
Altcode:
  We present high-precision relative radial velocities of the very
  low-mass star VB10 that were obtained over a time span of 0.61 yr as
  part of an ongoing search for planets around stars at the end of the
  main sequence. The radial velocities were measured from high-resolution
  near-infrared spectra obtained using the CRIRES instrument on the
  VLT with an ammonia gas cell. The typical internal precision of
  the measurements is 10 m/s. These data do not exhibit significant
  variability and are essentially constant at a level consistent
  with the measurement uncertainties. Therefore, we do not detect the
  radial velocity variations of VB10 expected due to the presence of
  an orbiting giant planet similar to that recently proposed by Pravdo
  and Shaklan based on apparent astrometric perturbations. In addition,
  we do not confirm the ~1 km/s radial velocity variability of the star
  tentatively detected by Zapatero Osorio and colleagues with lower
  precision measurements. Our measurements rule out planets with M_p &gt;
  3 M_Jup and the orbital period and inclination suggested by Pravdo and
  Shaklan at better than 5 sigma confidence. We conclude that the planet
  detection claimed by Pravdo and Shaklan is spurious on the basis of
  this result. Although the outcome of this work is a non-detection,
  it illustrates the potential of using ammonia cell radial velocities
  to detect planets around very low-mass stars.

Title: Physical Properties of the 0.94-Day Period Transiting Planetary
    System WASP-18
Authors: Southworth, John; Hinse, T. C.; Dominik, M.; Glitrup, M.;
   Jørgensen, U. G.; Liebig, C.; Mathiasen, M.; Anderson, D. R.; Bozza,
   V.; Browne, P.; Burgdorf, M.; Calchi Novati, S.; Dreizler, S.; Finet,
   F.; Harpsøe, K.; Hessman, F.; Hundertmark, M.; Maier, G.; Mancini,
   L.; Maxted, P. F. L.; Rahvar, S.; Ricci, D.; Scarpetta, G.; Skottfelt,
   J.; Snodgrass, C.; Surdej, J.; Zimmer, F.
Bibcode: 2009ApJ...707..167S
Altcode: 2009arXiv0910.4875S
  We present high-precision photometry of five consecutive transits
  of WASP-18, an extrasolar planetary system with one of the shortest
  orbital periods known. Through the use of telescope defocusing we
  achieve a photometric precision of 0.47-0.83 mmag per observation over
  complete transit events. The data are analyzed using the JKTEBOP code
  and three different sets of stellar evolutionary models. We find the
  mass and radius of the planet to be M <SUB>b</SUB> = 10.43 ± 0.30 ±
  0.24 M <SUB>Jup</SUB> and R <SUB>b</SUB> = 1.165 ± 0.055 ± 0.014 R
  <SUB>Jup</SUB> (statistical and systematic errors), respectively. The
  systematic errors in the orbital separation and the stellar and
  planetary masses, arising from the use of theoretical predictions,
  are of a similar size to the statistical errors and set a limit on
  our understanding of the WASP-18 system. We point out that seven of
  the nine known massive transiting planets (M <SUB>b</SUB> &gt; 3 M
  <SUB>Jup</SUB>) have eccentric orbits, whereas significant orbital
  eccentricity has been detected for only four of the 46 less-massive
  planets. This may indicate that there are two different populations
  of transiting planets, but could also be explained by observational
  biases. Further radial velocity observations of low-mass planets will
  make it possible to choose between these two scenarios. <P />Based
  on data collected by MiNDSTEp with the Danish 1.54 m telescope at the
  ESO La Silla Observatory.

Title: A hot white dwarf luminosity function from the Sloan Digital
    Sky Survey
Authors: Krzesinski, J.; Kleinman, S. J.; Nitta, A.; Hügelmeyer,
   S.; Dreizler, S.; Liebert, J.; Harris, H.
Bibcode: 2009A&A...508..339K
Altcode:
  Aims. We present a hot white dwarf (WD) luminosity function (LF) using
  data taken from the Sloan Digital Sky Survey (SDSS) Data Release 4. We
  present and discuss a combined LF, along with separate DA and non-DA
  as LFs. We explore the completeness of our LFs and interpret a sudden
  drop in the non-DA LF near 2 M_bol as a transition of the non-DA WD
  atmosphere into the DA one during WD evolution. Our LF extends roughly
  between -0.5 &lt; M_bol &lt; 7 or equivalently, ∼ 120 000 K &gt;
  T_eff &gt; ∼25 000 K. Our LF should now be useful for estimates of
  recent star formation and for studies of neutrino and other potential
  particle emission losses in hot WDs. <BR /> Methods: To create a
  sample whose completeness can be characterized fully, we used stars
  whose spectra were obtained via the SDSS's “hot standard” target
  selection criteria. The hot standard stars were purposefully targeted to
  a high level of completeness by the SDSS for calibration purposes. We
  are fortunate that many of them are hot white dwarfs stars. We further
  limited the sample to stars with fitted temperatures exceeding 23
  500 K and log{g} &gt; 7.0. We determined stellar distances for our
  sample based on their absolute SDSS g filter magnitudes, derived from
  WD stellar atmosphere model fits to the SDSS stellar spectra. <BR />
  Results: We compared our LF with those of other researchers where
  overlap occurs; however, our LFs are unique in their extension to the
  most luminous/hottest WDs. The cool end of our LF connects with the
  hot end of previously determined SDSS WD LFs and agreement here is
  quite good. It is also good with previous non-SDSS WD LFs. We note
  distinct differences between the DA and non-DA LFs and discuss the
  reliability of the DA LF at its hot end. We have extended the range
  of luminosities covered in the most recent WD LFs. The SDSS sample
  is understood quite well and its exploration should contribute to a
  number of new insights into early white dwarf evolution. <BR />

Title: The Transit Ingress and the Tilted Orbit of the Extraordinarily
    Eccentric Exoplanet HD 80606b
Authors: Winn, Joshua N.; Howard, Andrew W.; Johnson, John Asher;
   Marcy, Geoffrey W.; Gazak, J. Zachary; Starkey, Donn; Ford, Eric B.;
   Colón, Knicole D.; Reyes, Francisco; Nortmann, Lisa; Dreizler, Stefan;
   Odewahn, Stephen; Welsh, William F.; Kadakia, Shimonee; Vanderbei,
   Robert J.; Adams, Elisabeth R.; Lockhart, Matthew; Crossfield, Ian J.;
   Valenti, Jeff A.; Dantowitz, Ronald; Carter, Joshua A.
Bibcode: 2009ApJ...703.2091W
Altcode: 2009arXiv0907.5205W
  We present the results of a transcontinental campaign to observe the
  2009 June 5 transit of the exoplanet HD 80606b. We report the first
  detection of the transit ingress, revealing the transit duration to be
  11.64 ± 0.25 hr and allowing more robust determinations of the system
  parameters. Keck spectra obtained at midtransit exhibit an anomalous
  blueshift, giving definitive evidence that the stellar spin axis and
  planetary orbital axis are misaligned. The Keck data show that the
  projected spin-orbit angle λ is between 32° and 87° with 68.3%
  confidence and between 14° and 142° with 99.73% confidence. Thus,
  the orbit of this planet is not only highly eccentric (e = 0.93) but is
  also tilted away from the equatorial plane of its parent star. A large
  tilt had been predicted, based on the idea that the planet's eccentric
  orbit was caused by the Kozai mechanism. Independently of the theory,
  it is worth noting that all three exoplanetary systems with known
  spin-orbit misalignments have massive planets on eccentric orbits,
  suggesting that those systems migrate through a different channel than
  lower mass planets on circular orbits.

Title: 1D and 3D radiative transfer in circumstellar disks
Authors: Hügelmeyer, S. D.; Dreizler, S.; Homeier, D.; Hauschildt,
   P. H.; Barman, T.
Bibcode: 2009AIPC.1171...93H
Altcode:
  We present our code for the calculation of the 1D structure and
  synthetic spectra of accretion disks. The code is an extension of the
  well-tested stellar atmosphere code PHOENIX and is therefore capable
  of including large lists of atomic and molecular lines as well as
  a large set of dust species. We assume the standard accretion disk
  model for geometrically thin disks and solve the radiative transfer
  equation in the vertical direction for a number of disk rings with
  different radii. The combination of these rings yields the total disk
  spectrum. Comparison to observations of the T Tauri star GQ Lup shows
  the capability of our code. Additionally, we will show first results of
  3D radiative transfer calculations. We plan to investigate the effect
  of rotating disks on the line profile by means of a two-level atom.

Title: Detecting circumstellar disks around gravitational microlenses
Authors: Hundertmark, M.; Hessman, F. V.; Dreizler, S.
Bibcode: 2009A&A...500..929H
Altcode: 2009arXiv0904.1117H
  Aims: We investigate the chance of detecting proto-planetary or debris
  disks in stars that induce microlensing event (lenses), and consider
  the modification of the light curve shapes due to occultation and
  extinction by the disks, as well as the gravitational deflection
  caused by the additional mass. <BR />Methods: The magnification
  of gravitational microlensing events is calculated using the ray
  shooting method. The occultation is taken into account by neglecting
  or weighting the images on the lens plane according to a transmission
  map of the corresponding disk for a point source point lens (PSPL)
  model. The estimated frequency of events is obtained by considering the
  possible inclinations and optical depths of the disk. <BR />Results:
  We conclude that gravitational microlensing can be used, in principle,
  as a tool for detecting debris disks beyond 1 kpc, but estimate that
  each year around 1 debris disk is expected for lens stars of F, G, or
  K spectral type and about 10 debris disks might have shown signatures
  in existing datasets.

Title: Spectral synthesis of circumstellar disks - application to
    white dwarf debris disks
Authors: Hügelmeyer, S. D.; Dreizler, S.; Homeier, D.; Hauschildt, P.
Bibcode: 2009JPhCS.172a2060H
Altcode: 2009arXiv0905.0329H
  Gas and dust disks are common objects in the universe and can be
  found around various objects, e.g. young stars, cataclysmic variables,
  active galactic nuclei, or white dwarfs. The light that we receive from
  disks provides us with clues about their composition, temperature,
  and density. In order to better understand the physical and chemical
  dynamics of these disks, self-consistent radiative transfer simulations
  are inevitable. Therefore, we have developed a 1+1D radiative transfer
  code as an extension to the well-established model atmosphere code
  PHOENIX. We will show the potential of the application of our code to
  model the spectra of white dwarf debris disks.

Title: Spectral analysis of 636 WD - M star binaries from the Sloan
    Digital Sky Survey (Data Release 6)
Authors: Heller, R.; Homeier, D.; Dreizler, S.; Østensen, R.
Bibcode: 2009JPhCS.172a2023H
Altcode:
  We present a catalog of 857 WD (WD)-M star binaries from the sixth
  data release of the Sloan Digital Sky Survey (SDSS), most of them
  known before. For 636 of them, we give a spectral analysis and derive
  the basic parameters of the stellar constituents and their distances
  from Earth. Our purpose is to test the modeled spectra applied in
  the fitting procedure on the one hand and to confine the respective
  evolutionary scenarios on the other hand. We use a χ<SUP>2</SUP>
  minimization technique in order to decompose each combined spectrum
  and yield independent parameter estimates for the components. 41 of the
  stellar duets in our spectroscopic sample are optically resolved on the
  respective SDSS images. Despite various selection effects, the fraction
  of 6.4 % of WD-M star binaries with orbital separation around 500 AU and
  orbital perdiods of ~ 10<SUP>4</SUP> yr is a criterion for evolutionary
  models of stellar binary systems. We find 20 out of 636 WDs being
  fitted as DOs, with 16 of them indicating T<SUB>ef</SUB><SUP>WD</SUP>
  around 40000K. This excess of cool DOs is most likely due to additional
  WDs in the DB-DO T<SUB>eff</SUB> range, for which no detailed fitting
  was done. Furthermore, we identify 70 very low-mass objects, meaning
  secondaries with masses smaller than about 0.1 M<SUB>odot</SUB>, as
  candidate substellar companions. A trend of WD masses towards higher
  values in a binary constellation compared to those of field WDs is
  compatible with our results.

Title: SDSS DR4: Progress on the hot white dwarf luminosity function
Authors: Krzesinski, J.; Nitta, A.; Kleinman, S. J.; Hügelmeyer,
   S.; Dreizler, S.; Liebert, J.; Harris, H.
Bibcode: 2009JPhCS.172a2002K
Altcode:
  A large collection of white dwarf (WD) spectra from Sloan Digital
  Sky Survey (SDSS) data release 4 (DR4) WD catalog data allowed us
  to obtain a luminosity function (LF) for the hottest WDs. The LF was
  calculated basing on spectra of the WDs from a special class of SDSS
  objects called hot standards (HS), for which the WD sample completeness
  can be estimated. WD distances were determined from the observed and
  absolute SDSS g filter magnitudes derived from WD stellar atmosphere
  model fits to the SDSS spectra. The result LF covers -0.5 up to 7
  absolute bolometric magnitude range. It shows a slight disagreement
  at the cold end comparing to the literature LFs but it can be due
  to some problems with HS WD sample completeness estimations. It is
  clearly visible that the LF has unexpected plateau between 1.5 and
  4 absolute bolometric magnitudes. There is nothing similar visible
  in a LF built only for non-DA WDs. The plateau might be real but we
  are concern that its existence can be connected to the problems with
  spectra calibration of the blue objects in SDSS DR4 data and lack of
  good stellar atmosphere models for the hottest DA white dwarfs.

Title: Non-LTE spectral analyses of the lately discovered DB-gap
    white dwarfs from the SDSS
Authors: Hügelmeyer, S. D.; Dreizler, S.
Bibcode: 2009JPhCS.172a2048H
Altcode: 2009arXiv0905.0331H
  For a long time, no hydrogen-deficient white dwarfs have been
  known that have effective temperature between 30 kK and &lt; 45 kK,
  i. e. exceeding those of DB white dwarfs and having lower ones than DO
  white dwarfs. Therefore, this temperature range was long known as the
  DB-gap. Only recently, the SDSS provided spectra of several candidate
  DB-gap stars. First analyses based on model spectra calculated under
  the assumption of local thermodynamic equilibrium (LTE) confirmed that
  these stars had 30 kK &lt; T<SUB>eff</SUB> &lt; 45 kK (Eisenstein et
  al. 2006). It has been shown for DO white dwarfs that the relaxation
  of LTE is necessary to account for non local effects in the atmosphere
  caused by the intense radiation field. Therefore, we calculated a
  non-LTE model grid and re-analysed the aforementioned set of SDSS
  spectra. Our results confirm the existence of DB-gap white dwarfs.

Title: On the possibility of detecting extrasolar planets' atmospheres
    with the Rossiter-McLaughlin effect
Authors: Dreizler, S.; Reiners, A.; Homeier, D.; Noll, M.
Bibcode: 2009A&A...499..615D
Altcode: 2009arXiv0903.2217D
  Context: The detection of extrasolar planets' atmospheres requires
  very demanding observations. For planets that cannot be spatially
  separated from their host stars, i.e. the vast majority of planets,
  the transiting planets are the only ones to allow their atmospheres
  to be probed. This is possible from transmission spectroscopy
  or from measurements taken during the secondary eclipse. An
  alternative is to measure of the Rossiter-McLaughlin effect, which
  is sensitive to the size of the planetary radius. Since the radius
  is wavelength-dependent due to contributions of strong planetary
  absorption lines, this opens a path toward also probing planetary
  atmospheres with ground-based high-resolution spectroscopy. <BR
  />Aims: The major goal of our numerical simulations is to provide
  a reliable estimate of the amplitude of the wavelength-dependent
  Rossiter-McLaughlin effect. <BR />Methods: Our numerical simulations
  provide detailed phase-resolved synthetic spectra modeling the partly
  eclipsed stellar surface during the transit. With these spectra
  we can obtain Rossiter-McLaughlin curves for different wavelength
  regions and for a wavelength-dependent planetary radius. Curves from
  regions with high and low contributions of absorption lines within
  the planetary atmosphere can be compared. Observable quantities are
  derived from these differential effects. <BR />Results: We applied
  our simulations to HD 209458. Our numerical simulations show that a
  detailed treatment of the limb-darkening for the synthetic spectra
  is important for a precise analysis. Compared to a parameterized
  limb-darkening law, systematic errors of 6 m s<SUP>-1</SUP> occur. The
  wavelength dependency of the planetary atmospheres over the NaD-doublet
  produces a differential effect in the Rossiter-McLaughlin curve of
  1.5 m s<SUP>-1</SUP> for a star with a rotation velocity of 4.5 km
  s<SUP>-1</SUP>, which increases to 4 m s<SUP>-1</SUP> for twice the
  rotation velocity. <BR />Conclusions: As a tool for probing planetary
  atmospheres the Rossiter-McLaughlin effect requires phase-resolved,
  high signal-to-noise, high-resolution spectra taken with a stabilized
  spectrograph in order to obtain reliable results for slowly rotating
  (&lt;10 m s<SUP>-1</SUP>) planet host stars. Stars with spectral type
  earlier than about F5 are a bit less demanding since the typically
  higher rotation velocity increases the amplitude of the effect to about
  15 m s<SUP>-1</SUP> for a star with v sin i = 25 km s<SUP>-1</SUP>.

Title: Radiative transfer in circumstellar disks. I. 1D models for
    GQ Lupi
Authors: Hügelmeyer, S. D.; Dreizler, S.; Hauschildt, P. H.; Seifahrt,
   A.; Homeier, D.; Barman, T.
Bibcode: 2009A&A...498..793H
Altcode: 2009arXiv0903.2381H
  We present a new code for the calculation of the 1D structure and
  synthetic spectra of accretion disks. The code is an extension of the
  general purpose stellar atmosphere code PHOENIX and is therefore capable
  of including extensive lists of atomic and molecular lines as well as
  dust in the calculations. We assume that the average viscosity can be
  represented by a critical Reynolds number in a geometrically thin disk
  and solve the structure and radiative transfer equations for a number
  of disk rings in the vertical direction. The combination of these
  rings provides the total disk structure and spectrum. Since the warm
  inner regions of protoplanetary disks show a rich molecular spectrum,
  they are well suited for a spectral analysis with our models. In this
  paper we test our code by comparing our models with high-resolution
  VLT CRIRES spectra of the T Tauri star GQ Lup.

Title: OGLE2-TR-L9b: an exoplanet transiting a rapidly rotating
    F3 star
Authors: Snellen, I. A. G.; Koppenhoefer, J.; van der Burg, R. F. J.;
   Dreizler, S.; Greiner, J.; de Hoon, M. D. J.; Husser, T. O.; Krühler,
   T.; Saglia, R. P.; Vuijsje, F. N.
Bibcode: 2009A&A...497..545S
Altcode: 2008arXiv0812.0599S
  Context: The photometric observations of the OGLE-II microlens
  monitoring campaign have been taken in the period 1997-2000. All light
  curves of this campaign have recently become public. Our analysis of
  these data has revealed 13 low-amplitude transiting objects among
  15 700 stars in three Carina fields towards the Galactic disk. One
  of these objects, OGLE2-TR-L9 (P∼2.5 days), turned out to be an
  excellent transiting-planet candidate. <BR />Aims: We report on our
  investigation of the true nature of OGLE2-TR-L9. By re-observing the
  photometric transit, we attempt to determine the transit parameters to
  high precision, and, by spectroscopic observations, to estimate the
  properties of the host star and determine the mass of the transiting
  object by means of radial-velocity measurements. <BR />Methods:
  High precision photometric observations were obtained in g',
  r', i', and z' band simultaneously, using the new GROND detector,
  mounted on the MPI/ESO 2.2 m telescope at La Silla. Eight epochs of
  high-dispersion spectroscopic observations were obtained using the
  fiber-fed FLAMES/UVES Echelle spectrograph, mounted on ESO's Very Large
  Telescope at Paranal. <BR />Results: The photometric transit, now more
  than 7 years after the last OGLE-II observations, was re-discovered
  only 8 min from its predicted time. The primary object is a rapidly
  rotating F3 star with v sin i=39.33±0.38 km s<SUP>-1</SUP>, T=6933±58
  K, log g = 4.25±0.01, and [Fe/H] = -0.05±0.20. The transiting object
  is an extrasolar planet with M<SUB>{p</SUB>}=4.5±1.5 M<SUB>{Jup</SUB>}
  and R<SUB>{p</SUB>}=1.61±0.04 R<SUB>{Jup</SUB>}. Since this is the
  first planet detected orbiting a fast rotating star, the uncertainties
  in both the radial-velocity measurements and the planetary mass are
  larger than for most other planets discovered to date. The rejection
  of possible blend scenarios was based on a quantitative analysis of
  the multi-color photometric data. A stellar-blend scenario of an early
  F-star with a faint eclipsing-binary system is excluded, due to 1) the
  consistency between the spectroscopic parameters of the star and the
  mean density of the transited object as determined from the photometry,
  and 2) the excellent agreement between the transit signal as observed
  at four different wavelengths. <P />Based on observations collected
  at the European Organisation for Astronomical Research in the Southern
  Hemisphere, Chile (280.C-5036(A)).

Title: VizieR Online Data Catalog: Spectral analysis of 636 SDSS
    WD-M binaries (Heller+, 2009)
Authors: Heller, R.; Homeier, D.; Dreizler, S.; Oestensen, R.
Bibcode: 2009yCat..34960191H
Altcode:
  We present a catalog of 857 WD-M star binaries from the Sloan Digital
  Sky Survey (SDSS), most of which were previously identified by other
  authors, and the results of our spectral analysis for a subsample of
  636 WD-M composite spectra. Our automatic fitting procedure bases on a
  chi<SUP>2</SUP> minimization technique, yielding a decomposition of each
  combined spectrum and a derivation of independent parameter estimates
  for both components. On the respective photometric data from the SDSS,
  we also find 41 optically resolved binaries. We also investigated the
  spectra for hydrogen and helium emission. <P />(3 data files).

Title: The planet-hosting subdwarf B star <ASTROBJ>V 391
    Pegasi</ASTROBJ> is a hybrid pulsator
Authors: Lutz, R.; Schuh, S.; Silvotti, R.; Bernabei, S.; Dreizler,
   S.; Stahn, T.; Hügelmeyer, S. D.
Bibcode: 2009A&A...496..469L
Altcode: 2009arXiv0901.4523L
  Context: A noticeable fraction of subdwarf B stars shows either
  short-period (p-mode) or long-period (g-mode) luminosity variations,
  with two objects so far known to exhibit hybrid behaviour, i.e. showing
  both types of modes at the same time. The pulsating subdwarf B star
  <ASTROBJ>V 391 Pegasi</ASTROBJ> (or <ASTROBJ>HS 2201+2610</ASTROBJ>),
  which is close to the two known hybrid pulsators in the log
  g-T_eff plane, has recently been discovered to host a planetary
  companion. <BR />Aims: In order to learn more about the planetary
  companion and its possible influence on the evolution of its host star
  (subdwarf B star formation is still not well understood), an accurate
  characterisation of the host star is required. As part of an ongoing
  effort to significantly improve the asteroseismic characterisation
  of the host star, we investigate the low-frequency behaviour of
  <ASTROBJ>HS 2201+2610</ASTROBJ>. <BR />Methods: We obtained rapid high
  signal-to-noise photometric CCD (B-filter) and PMT (clear-filter)
  data at 2 m-class telescopes and carried out a careful frequency
  analysis of the light curves. <BR />Results: In addition to the
  previously known short-period luminosity variations in the range 342
  s-367 s, we find a long-period variation with a period of 54 mn and an
  amplitude of 0.15 per cent. This can most plausibly be identified with
  a g-mode pulsation, so that <ASTROBJ>HS 2201+2610</ASTROBJ> is a new
  addition to the short list of hybrid sdB pulsators. <BR />Conclusions:
  Along with the previously known pulsating subdwarf B stars <ASTROBJ>HS
  0702+6043</ASTROBJ> and <ASTROBJ>Balloon 090100001</ASTROBJ> showing
  hybrid behaviour, the new hybrid <ASTROBJ>HS 2201+2610</ASTROBJ> is
  the third member of this class. This important property of <ASTROBJ>HS
  2201+2610</ASTROBJ> can lead to a better characterisation of this
  planet-hosting star, helping the characterisation of its planetary
  companion as well. Current pulsation models cannot yet reproduce
  hybrid sdBV stars particularly well and improved pulsation models
  for this object have to include the hybrid behaviour. <P />Based
  on observations collected at the Centro Astronómico Hispano Alemán
  (CAHA) at Calar Alto, <P />operated jointly by the Max-Planck Institut
  für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC).

Title: Spectral analysis of 636 white dwarf-M star binaries from
    the sloan digital sky survey
Authors: Heller, R.; Homeier, D.; Dreizler, S.; Østensen, R.
Bibcode: 2009A&A...496..191H
Altcode:
  Context: We present a catalog of 857 white dwarf (WD)-M binaries from
  the sixth data release (DR6) of the Sloan Digital Sky Survey (SDSS),
  most of which were previously identified. For 636 of them, we complete
  a spectral analysis and derive the basic parameters of their stellar
  constituents and their distances from Earth. <BR />Aims: We attempt to
  measure fundamental parameters of these systems by completing spectral
  analyses. We propose to test models typically applied in fitting
  procedures and constrain likely and appropriate evolutionary scenarios
  for the systems. <BR />Methods: We use a χ<SUP>2</SUP> minimization
  technique to decompose each combined spectrum and derive independent
  parameter estimates for its components. The possibility of alignment by
  chance is demoted to statistical insignificance, hence, we use physical
  interaction of the binary constituents as input parameter. Additionally,
  we check the corresponding photometric data from the SDSS to find
  optically resolved systems. <BR />Results: Forty-one of the stellar
  duets in our spectroscopic sample are optically resolved in their
  respective SDSS images. For these systems, we also derive a minimum
  true spatial separation and a lower limit to their orbital periods,
  typically which are some 10<SUP>4</SUP> yr. Spectra of 167 stellar duets
  show significant hydrogen emission and in most cases no additional He
  i or He ii features. We also find that 20 of the 636 WDs are fitted to
  be DOs, with 16 measured to have T<SUB>eff</SUB><SUP>WD</SUP> around
  40 000 K. Furthermore, we identify 70 very low-mass objects (VLMOs),
  which are secondaries of masses smaller than about 0.1 M<SUB>⊙</SUB>,
  to be candidate substellar companions. <BR />Conclusions: Although
  various selection effects may play a role, the fraction 6.4% of WD-M
  star binaries with orbital separations of around 500 AU is a criterion
  for evolutionary models of stellar binary systems. Of the 167 spectra
  with hydrogen emission, 8 had already been found to be post-common
  envelope binaries (PCEBs) and 4 are systems with strong irradiation
  processes on the M dwarf. The remaining 155 Balmer-emitting binaries
  probably harbor an active M dwarf (dM), corresponding to a fraction
  of 24.4%. The excess of cool DOs is most likely due to additional WDs
  in the DB-DO T<SUB>eff</SUB> range, for which no detailed fitting was
  completed. The trend of the M stars being closer to Earth than the WD
  component is probably due to an underestimation of the theoretical M
  star radii.

Title: Long-term EXOTIME photometry and follow-up spectroscopy of
    the sdB pulsator HS 0702+6043
Authors: Lutz, R.; Schuh, S.; Silvotti, R.; Kruspe, R.; Dreizler, S.
Bibcode: 2009CoAst.159...94L
Altcode: 2009arXiv0901.4514L
  Pulsating subdwarf B (sdB) stars oscillate in short-period p modes or
  long-period g modes. HS 0702+6043 (DW Lyn) is one of a few objects to
  show characteristics of both types and is hence classified as a hybrid
  pulsator. It is one of our targets in the EXOTIME program to search
  for planetary companions around extreme horizontal branch objects. In
  addition to the standard exercise in asteroseismology to probe the
  instantaneous inner structure of a star, measured changes in the
  pulsation frequencies as derived from an O--C diagram can be compared
  to theoretical evolutionary time scales. Based on the photometric data
  available so far, we are able to derive a high-resolution frequency
  spectrum and to report our efforts to construct a multi-season O--C
  diagram. Additionally, we have gathered time-resolved spectroscopic
  data in order to constrain stellar parameters and to derive mode
  parameters as well as radial and rotational velocities.

Title: Spectral synthesis of inner gaseous protoplanetary disks
    with PHOENIX
Authors: Hügelmeyer, S. D.; Dreizler, S.; Homeier, D.; Hauschildt,
   P. H.; Barman, T.
Bibcode: 2009AIPC.1094..389H
Altcode: 2009csss...15..389H
  The inner gaseous regions of protoplanetary disks are of special
  interest in the formation and evolution of planets and stars because
  they are the likely birthplaces of planets and serve as the accretion
  reservoir for young stars. The study of inner disks may give rise to a
  better understanding of the dynamics, physical and chemical structure,
  and gas content of the region. As a first step, we have developed a 1+1D
  disk radiative transfer package as an extension to the well established
  multipurpose stellar atmosphere program PHOENIX. The solution of
  the equations of momentum and energy conservation as well as the
  radiative transfer equation is adopted for the physical conditions in
  and the geometry of disks. Irradiation by the central star is treated in
  detail. Comparison of our models with high-resolution infrared spectra
  will enable us to constrain the structure, dynamics, and gas content of
  disks, and thus give new insights on the physical processes governing
  star and planet formation. Additionally, we present our current
  construction site: a 3D radiative transfer code for accretion disks.

Title: Spectral Analysis of 636 White Dwarf-M Star Binaries from
    the Sloan Digital Sky Survey
Authors: Heller, R.; Homeier, D.; Dreizler, S.; Østensen, R.
Bibcode: 2009AIPC.1094..931H
Altcode: 2009csss...15..931H; 2008arXiv0811.1508H
  We present a catalog of 857 white dwarf-M binaries from the sixth data
  release of the Sloan Digital Sky Survey (SDSS), most of them known
  before. For 636 of them, we give a spectral analysis and derive the
  basic parameters of the stellar constituents and their distances from
  Earth. The analysis shall give a statistically relevant statement about
  the fundamental parameters of such systems. Our purpose is to test
  the models applied in the fitting procedure on the one hand and to
  confine the respective evolutionary scenarios on the other hand. The
  χ<SUP>2</SUP> minimization technique we use, in order to decompose
  each combined spectrum and yield independent parameter estimates for the
  components, differs from that typically applied to break down combined
  spectra. In the corresponding SDSS photometric data we find 41 optically
  resolved systems. For these we also derive a minimum real spatial
  separation and a lower limit for the orbital periods-typically some
  10<SUP>4</SUP> yr. 167 spectra show significant hydrogen emission and
  mostly no additional He I or He II features. Furthermore, we identify
  70 very low-mass objects, meaning secondaries with masses smaller than
  about 0.1 M<SUB>solar</SUB>, as candidate substellar companions.

Title: New Science Opportunities Offered by MUSE
Authors: Bacon, R.; Bauer, S.; Brau-Nogué, S.; Caillier, P.; Capoani,
   L.; Carollo, M.; Contini, T.; Daguisé, E.; Delabre, B.; Dreizler,
   S.; Dubois, J. P.; Dupieux, M.; Dupin, J.; Emsellem, E.; Ferruit,
   P.; Francois, M.; Franx, M.; Gallou, G.; Gerssen, J.; Guiderdoni,
   B.; Hansali, G.; Hofmann, D.; Jarno, A.; Kelz, A.; Koehler, C.;
   Kollatschny, W.; Kosmalski, J.; Laurent, F.; Lilly, S.; Lizon, J.;
   Loupias, M.; Monstein, C.; Moultaka, J.; Nicklas, H.; Parés, L.;
   Pasquini, L.; Pecontal, A.; Pello, R.; Petit, C.; Manescau, A.; Reiss,
   R.; Remillieux, A.; Renault, E.; Roth, M.; Schaye, J.; Steinmetz,
   M.; Ströbele, S.; Stuik, R.; Weilbacher, P.; Wisotzki, L.; Wozniak, H.
Bibcode: 2009ASSP....9..331B
Altcode: 2009svlt.conf..331B
  The Multi Unit Spectroscopic Explorer MUSE [MUSE public web site:
  http://muse.univ-lyon1.fr] is one of the second generation VLT
  instruments. MUSE is a wide-field optical integral field spectrograph
  operating in the visible wavelength range with improved spatial
  resolution. The MUSE Consortium consists of groups at Lyon (PI
  institute, CRAL), Gottingen (IAG), Potsdam (AIP), Leiden (NOVA),
  Toulouse (LATT), Zurich (ETH) and ESO. The project is currently in its
  final design phase. Manufacturing, assembly and integration will start
  after the Final Design Review which is foreseen for late 2008. The
  Preliminary acceptance in Europe is scheduled for mid 2011 and the
  instrument shall be in operation at Paranal in 2012.

Title: Multi-wavelength photometric variation of PG 1605+072
Authors: Schuh, S.; Dreizler, S.; Heber, U.; Jeffery, C. S.; O'Toole,
   S. J.; Cordes, O.; Stahn, T.; Lutz, R.; Tillich, A.; Wet and MSST
   Collaborations
Bibcode: 2008CoAst.157...35S
Altcode: 2008arXiv0812.4857S
  In a large coordinated attempt to further our understanding of the
  p-mode pulsating sdB star PG 1605+072, the Multi-Site Spectroscopic
  Telescope (MSST) collaboration has obtained simultaneous time-resolved
  spectroscopic and photometric observations. The photometry was extended
  by additional WET data which increased the time base. This contribution
  outlines the analysis of the MSST photometric light curve, including
  the four-colour BUSCA data from which chromatic amplitudes have been
  derived, as well as supplementary FUV spectra and light curves from
  two different epochs. These results have the potential to complement
  the interpretation of the published spectroscopic information.

Title: Long-term photometric monitoring of the hybrid subdwarf B
    pulsator HS 0702+6043
Authors: Lutz, R.; Schuh, S.; Silvotti, R.; Kruspe, R.; Dreizler, S.
Bibcode: 2008CoAst.157..185L
Altcode: 2008arXiv0812.4859L
  Pulsating subdwarf B stars oscillate in short-period p-modes or
  long-period g-modes. HS 0702 +6043 is one of the three objects currently
  known to show characteristics of both types and hence is classified
  as hybrid pulsator. We briefly present our analysis of the g-mode
  domain of this star, but focus on the first results from long-term
  photometric monitoring in particular of the p-mode oscillations. We
  present a high-resolution frequency spectrum, and report on our
  efforts to construct a multi-season O C diagram. Additionally to the
  standard (although nontrivial) exercise in asteroseismology to probe
  the instantaneous inner structure of a star, measured changes in the
  pulsation frequencies as derived from an O C diagram can be compared
  to theoretical evolutionary timescales. Within the EXOTIME program,
  we also use this same data to search for planetary companions around
  extreme horizontal branch objects (”asteroseismic planets”).

Title: A Hubble Space Telescope transit light curve for GJ 436b
Authors: Bean, J. L.; Benedict, G. F.; Charbonneau, D.; Homeier, D.;
   Taylor, D. C.; McArthur, B.; Seifahrt, A.; Dreizler, S.; Reiners, A.
Bibcode: 2008A&A...486.1039B
Altcode: 2008arXiv0806.0851B
  We present time series photometry for six partial transits
  of GJ 436b obtained with the Fine Guidance Sensor instrument
  on the Hubble Space Telescope (HST). Our analysis of these
  data yields independent estimates of the host star's radius
  R<SUB>star</SUB> = 0.505<SUP>+0.029</SUP><SUB>-0.020</SUB>
  R<SUB>⊙</SUB>, and the planet's orbital period P =
  2.643882^+0.000060<SUB>-0.000058</SUB> d, orbital inclination i =
  85.80° <SUP>+0.21°</SUP><SUB>-0.25°</SUB>, mean central transit time
  T<SUB>c</SUB> = 2 454 455.279241<SUP>+0.00026</SUP><SUB>-0.00025</SUB>
  HJD, and radius R<SUB>p</SUB> = 4.90<SUP>+0.45</SUP><SUB>-0.33</SUB>
  R<SUB>⊕</SUB>. The radius we determine for the planet is larger than
  the previous findings from analyses of an infrared light curve obtained
  with the Spitzer Space Telescope. Although this discrepancy has a 92%
  formal significance (1.7σ), it might be indicative of systematic errors
  that still influence the analyses of even the highest-precision transit
  light curves. Comparisons of all the measured radii to theoretical
  models suggest that GJ 436b has a H/He envelope of 10% by mass. We point
  out the similarities in structure between this planet and Uranus and
  Neptune and discuss possible parallels between these planets' formation
  environments and dynamical evolution. We also find that the transit
  times for GJ 436b are constant to within 10 s over the 11 planetary
  orbits that the HST data span. However, the ensemble of published
  values exhibits a long-term drift and our mean transit time is 128 s
  later than that expected from the Spitzer ephemeris. The sparseness of
  the currently available data hinders distinguishing between an error in
  the orbital period or perturbations arising from an additional object
  in the system as the cause of the apparent trend. Assuming the drift is
  due to an error in the orbital period we obtain an improved estimate
  for it of P = 2.643904 ± 0.000005 d. This value and our measured
  transit times will serve as important benchmarks in future studies of
  the GJ 436 system. <P />Table 2 is only available in electronic form
  at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)
  or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/486/1039

Title: VizieR Online Data Catalog: HST transit light curve for GJ436b
    (Bean+, 2008)
Authors: Bean, J. L.; Benedict, G. F.; Charbonneau, D.; Homeier, D.;
   Taylor, D. C.; McArthur, B.; Seifahrt, A.; Dreizler, S.; Reiners, A.
Bibcode: 2008yCat..34861039B
Altcode:
  This is Table 2 from the above paper. It contains photometric time
  series of 6 partial transits for GJ436b obtained with the FGS instrument
  on HST. The first column gives the visit number, the second one gives
  the date as Heliocentric Julian Days (HJD), the third one gives the
  flux in 60 second bins normalized by the reference star observations,
  and the fourth one gives the statistical noise for each measurement. <P
  />(1 data file).

Title: Hot DO and DB White Dwarfs from the Sloan Digital Sky Survey
Authors: Liebert, J.; Krzesinski, J.; Hügelmeyer, S.; Dreizler, S.
Bibcode: 2008ASPC..391..227L
Altcode:
  Hot DB and DO stars found in the Sloan Digital Sky Survey are
  analyzed. We note first that the mass distribution of DB stars
  determined by others has a very similar mean to that for samples of DA
  stars, but lacks low and high mass outliers. Our working hypothesis
  is that the missing high mass DB stars may simply be observed as hot
  DQ white dwarfs. The recent discovery of DB stars in the alleged ``DB
  gap'' at 30,000 - 45,000 K is discussed. Temperatures are estimated from
  both fits to the spectra and to the energy distributions. A deficit of
  stars in this range still seems likely, which would imply that about
  10% of DA evolve into DB stars below 30,000 K. We are working towards
  a preliminary luminosity function of DO-DB white dwarfs.

Title: XMM-Newton Observations of Two Soft X-Ray Selected Magnetic CVs
Authors: Traulsen, I.; Reinsch, K.; Dreizler, S.
Bibcode: 2008ASPC..391..287T
Altcode:
  The two AM Her type systems AI Tri and QS Tel have been monitored
  with the X-ray satellite XMM-Newton with 20 ksec exposures each
  and additional optical photometry at several sites during high and
  intermediate high states of accretion. The light curves are dominated
  by highly variable soft X-ray emission arising from the accretion
  heated surface of the white dwarf primary in addition to a weaker
  hard component reflecting the contribution of the multi-temperature
  thermal plasma emission from the post-shock accretion column. A mildly
  absorbed blackbody plus MEKAL plasma emission with variable element
  abundances describe the associated spectra. Evident discrepancies
  between the observed X-ray spectrum and the blackbody approximation
  emphasize the need for accurate models including radiative transfer
  to reproduce the white dwarf's contribution in a more realistic way.

Title: New Views of the Horizontal Branch in ω Centauri
Authors: Moehler, S.; Dreizler, S.; Lanz, T.; Bono, G.; Sweigart,
   A. V.; Calamida, A.; Monelli, M.; Nonino, M.
Bibcode: 2008ASPC..392...47M
Altcode:
  UV observations of some massive globular clusters uncovered a
  significant population of very hot stars below the hot end of the
  horizontal branch, the so-called blue hook stars. This feature might
  be explained either by the late hot flasher scenario where stars
  experience the helium flash while on the white dwarf cooling curve
  or by the helium-rich sub-population recently postulated to exist in
  some clusters. Previous spectroscopic analyses of blue hook stars in
  ω Cen and NGC 2808 support the late hot flasher scenario, but the
  stars were found to contain much less helium than expected and the
  predicted carbon and nitrogen enrichment could not be verified. New
  moderately high resolution spectra of stars at the hot end of the blue
  horizontal branch in ω Cen were analysed for atmospheric parameters
  ( T<SUB>eff</SUB>, log g, and log{n<SUB>He</SUB>}/{n<SUB>H</SUB>})
  and abundances using LTE and non-LTE model atmospheres. In the
  temperature range 30,000 K to 50,000 K we find that 35% of our
  stars are helium-poor (log{n<SUB>He</SUB>/{n<SUB>H</SUB>} &lt;
  -2), 51% have solar helium abundance within a factor of 3 (-1.5 ≤
  log{n<SUB>He</SUB>}/{n<SUB>H</SUB>} ≤ -0.5) and 14% are helium-rich
  (log{n<SUB>He</SUB>/{n<SUB>H</SUB>} &gt; -0.4). We also find carbon
  enrichment along with helium enrichment, with a maximum carbon abundance
  of 3% by mass. At least 14% of the hottest horizontal branch stars
  in ωCen show helium abundances well above the highest predictions
  from the helium enrichment scenario (Y≈ 0.42, corresponding to
  log{n<SUB>He</SUB>}/{n<SUB>H</SUB>} ≈ -0.74). In addition, the most
  helium-rich stars show high carbon abundances as predicted by the late
  hot flasher scenario. We conclude that the helium-rich horizontal branch
  stars in ω Cen cannot be explained solely by the helium-enrichment
  scenario invoked to explain the blue main sequence.

Title: MUSE: A Second-Generation Integral-Field Spectrograph for
    the VLT
Authors: McDermid, R. M.; Bacon, R.; Bauer, S.; Boehm, P.; Boudon,
   D.; Brau-Nogué, S.; Caillier, P.; Capoani, L.; Carollo, C. M.;
   Champavert, N.; Contini, T.; Daguisé, E.; Delabre, B.; Devriendt,
   J.; Dreizler, S.; Dubois, J.; Dupieux, M.; Dupin, J. P.; Emsellem, E.;
   Ferruit, P.; Franx, M.; Gallou, G.; Gerssen, J.; Guiderdoni, B.; Hahn,
   T.; Hofmann, D.; Jarno, A.; Kelz, A.; Koehler, C.; Kollatschny, W.;
   Kosmalski, J.; Laurent, F.; Lilly, S. J.; Lizon, J. L.; Loupias, M.;
   Manescau, A.; Monstein, C.; Nicklas, H.; Parès, L.; Pasquini, L.;
   Pécontal-Rousset, A.; Pécontal, E.; Pello, R.; Petit, C.; Picat,
   J. -P.; Popow, E.; Quirrenbach, A.; Reiss, R.; Renault, E.; Roth,
   M.; Schaye, J.; Soucail, G.; Steinmetz, M.; Stroebele, S.; Stuik,
   R.; Weilbacher, P.; Wisotzki, L.; Wozniak, H.; de Zeeuw, P. T.
Bibcode: 2008eic..work..325M
Altcode:
  The Multi Unit Spectroscopic Explorer (MUSE) is a second-generation
  instrument in development for the Very Large Telescope (VLT) of
  the European Southern Observatory (ESO), due to begin operation in
  2011/12. MUSE will be an extremely powerful integral-field spectrograph
  fed by a new multiple-laser adaptive optics system on the VLT. In its
  usual operating mode, MUSE will, in a single observation, produce
  a 3-dimensional data cube consisting of 90,000 R 3000 spectra,
  each covering a full spectral octave (480-930 nm), and fully
  sampling a contiguous 1×1 arcmin<SUP>2</SUP> field with 0.2×0.2
  arcsec<SUP>2</SUP> apertures. A high-resolution mode will increase
  the spatial sampling to 0.025 arcsec per pixel. MUSE is built around
  a novel arrangement of 24 identical spectrographs (each comparable
  to a 1st generation VLT instrument), which are fed by a set of 24
  precision image slicers. MUSE is designed for stability, with only 2
  modes, and virtually no moving parts, allowing very long exposures to
  be accumulated. Together with high throughput, this ensures that MUSE
  will have extreme sensitivity for observing faint objects. We overview
  the technical and scientific aspects of MUSE, highlighting the key
  challenges for dealing with the unprecedented quantity and complexity
  of the data, and the integration with the VLT adaptive optics facility
  (AOF) - a key development on the path to extremely large telescopes
  (ELTs).

Title: The pulsation modes of the pre-white dwarf PG 1159-035
Authors: Costa, J. E. S.; Kepler, S. O.; Winget, D. E.; O'Brien, M. S.;
   Kawaler, S. D.; Costa, A. F. M.; Giovannini, O.; Kanaan, A.; Mukadam,
   A. S.; Mullally, F.; Nitta, A.; Provençal, J. L.; Shipman, H.; Wood,
   M. A.; Ahrens, T. J.; Grauer, A.; Kilic, M.; Bradley, P. A.; Sekiguchi,
   K.; Crowe, R.; Jiang, X. J.; Sullivan, D.; Sullivan, T.; Rosen, R.;
   Clemens, J. C.; Janulis, R.; O'Donoghue, D.; Ogloza, W.; Baran, A.;
   Silvotti, R.; Marinoni, S.; Vauclair, G.; Dolez, N.; Chevreton, M.;
   Dreizler, S.; Schuh, S.; Deetjen, J.; Nagel, T.; Solheim, J. -E.;
   Gonzalez Perez, J. M.; Ulla, A.; Barstow, M.; Burleigh, M.; Good,
   S.; Metcalfe, T. S.; Kim, S. -L.; Lee, H.; Sergeev, A.; Akan, M. C.;
   Çakırlı, Ö.; Paparo, M.; Viraghalmy, G.; Ashoka, B. N.; Handler,
   G.; Hürkal, Ö.; Johannessen, F.; Kleinman, S. J.; Kalytis, R.;
   Krzesinski, J.; Klumpe, E.; Larrison, J.; Lawrence, T.; Meištas,
   E.; Martinez, P.; Nather, R. E.; Fu, J. -N.; Pakštienė, E.; Rosen,
   R.; Romero-Colmenero, E.; Riddle, R.; Seetha, S.; Silvestri, N. M.;
   Vučković, M.; Warner, B.; Zola, S.; Althaus, L. G.; Córsico, A. H.;
   Montgomery, M. H.
Bibcode: 2008A&A...477..627C
Altcode: 2007arXiv0711.2244C
  Context: <ASTROBJ>PG 1159-035</ASTROBJ>, a pre-white dwarf with
  T<SUB>eff</SUB>≃ 140 000 K, is the prototype of both two classes:
  the PG 1159 spectroscopic class and the DOV pulsating class. Previous
  studies of <ASTROBJ>PG 1159-035</ASTROBJ> photometric data obtained
  with the Whole Earth Telescope (WET) showed a rich frequency spectrum
  allowing the identification of 122 pulsation modes. Analyzing the
  periods of pulsation, it is possible to measure the stellar mass, the
  rotational period and the inclination of the rotation axis, to estimate
  an upper limit for the magnetic field, and even to obtain information
  about the inner stratification of the star. <BR />Aims: We have three
  principal aims: to increase the number of detected and identified
  pulsation modes in <ASTROBJ>PG 1159-035</ASTROBJ>, study trapping of the
  star's pulsation modes, and to improve or constrain the determination of
  stellar parameters. <BR />Methods: We used all available WET photometric
  data from 1983, 1985, 1989, 1993 and 2002 to identify the pulsation
  periods. <BR />Results: We identified 76 additional pulsation modes,
  increasing to 198 the number of known pulsation modes in <ASTROBJ>PG
  1159-035</ASTROBJ>, the largest number of modes detected in any star
  besides the Sun. From the period spacing we estimated a mass M/M_⊙ =
  0.59 ± 0.02 for <ASTROBJ>PG 1159-035</ASTROBJ>, with the uncertainty
  dominated by the models, not the observation. Deviations in the regular
  period spacing suggest that some of the pulsation modes are trapped,
  even though the star is a pre-white dwarf and the gravitational
  settling is ongoing. The position of the transition zone that causes
  the mode trapping was calculated at r_c/R_star = 0.83 ± 0.05. From
  the multiplet splitting, we calculated the rotational period P_rot =
  1.3920 ± 0.0008 days and an upper limit for the magnetic field, B &lt;
  2000 G. The total power of the pulsation modes at the stellar surface
  changed less than 30% for ℓ = 1 modes and less than 50% for ℓ =
  2 modes. We find no evidence of linear combinations between the 198
  pulsation mode frequencies. <ASTROBJ>PG 1159-035</ASTROBJ> models have
  not significative convection zones, supporting the hypothesis that
  nonlinearity arises in the convection zones in cooler pulsating white
  dwarf stars. <P />Tables [see full textsee full text]-[see full textsee
  full text] are only available in electronic form at http://www.aanda.org

Title: An Implementation of the Ray Shooting Method
Authors: Hundertmark, M.; Hessman, F.; Dreizler, S.
Bibcode: 2008mmc..confE..53H
Altcode: 2008PoS....54E..53H
  No abstract at ADS

Title: Light Curve Analysis of the Hybrid SdB PulsatorsHS 0702+6043
    and HS 2201+2610
Authors: Lutz, R.; Schuh, S.; Silvotti, R.; Dreizler, S.; Green,
   E. M.; Fontaine, G.; Stahn, T.; Hügelmeyer, S. D.; Husser, T. -O.
Bibcode: 2008ASPC..392..339L
Altcode: 2007arXiv0710.4871L
  We present the detection of low-amplitude, long-period g-modes in two
  individual sdBV stars which are known to be p-mode pulsators. Only
  few of these hybrid objects, showing both p- and g-modes, are known
  today. We resolve the g-mode domain in HS 0702+6043 and add HS 2201+2610
  to the list of hybrid pulsators. To discover the low-amplitude g-modes,
  a filtering algorithm based on wavelet transformations was applied to
  denoise observational data.

Title: Testing the Tidal Heating Hypothesis for the Transiting
    Exoplanets HAT-P-1b and TrES-4b
Authors: Armstrong, Amber; Bean, J. L.; McArthur, B.; Reiners, A.;
   Dreizler, S.; Benedict, G. F.
Bibcode: 2007AAS...21113409A
Altcode: 2007BAAS...39..969A
  One of the most interesting results that has emerged from the detection
  and study of transiting exoplanets is that some Hot Jupiters have
  larger radii, and thus lower densities, than models predict. A few
  mechanisms have been suggested as the cause of this, including one
  hypothesis that there is an unknown source of internal heat inflating
  these planets. Such a source of heat could be the dissipation of
  energy arising from the ongoing tidal circularization of the planets'
  eccentric orbits. However, the tidal circularization timescale
  for such close in planets is predicted to be at least an order of
  magnitude shorter than the putative ages of the systems. Therefore,
  if an inflated Hot Jupiter's orbital eccentricity is truly non-zero,
  there must be a perturber - possibly an additional undiscovered
  planet - in the system to regularly excite its eccentricity. We are
  currently carrying out high cadence and high precision radial velocity
  measurements of the host stars to inflated Hot Jupiters with the <P
  />Hobby-Eberly-Telescope to constrain their orbital eccentricities,
  search for additional planets in the systems, and ultimately test
  the tidal heating hypothesis. We present here preliminary results for
  the systems HAT-P-1 and TrES-4. At the time of this writing, TrES-4b
  is by far the lowest density exoplanet and the most discrepant from
  theoretical models. <P />Support for this work was provided by NASA
  through grants GO-10103, GO-10610, and GO-10989 from the Space Telescope
  Science Institute, which is operated by the Association of Universities
  for Research in Astronomy, Inc., under NASA <P />contract NAS5-26555.

Title: The hottest horizontal-branch stars in ω Centauri. Late hot
    flasher vs. helium enrichment
Authors: Moehler, S.; Dreizler, S.; Lanz, T.; Bono, G.; Sweigart,
   A. V.; Calamida, A.; Monelli, M.; Nonino, M.
Bibcode: 2007A&A...475L...5M
Altcode: 2007arXiv0709.2839M
  Context: UV observations of some massive globular clusters have revealed
  a significant population of very hot stars below the hot end of the
  horizontal branch (HB), the so-called blue hook stars. This feature
  might be explained either as a result of the late hot flasher scenario
  where stars experience the helium flash while on the white dwarf cooling
  curve or by the progeny of the helium-enriched sub-population recently
  postulated to exist in some clusters. Previous spectroscopic analyses
  of blue hook stars in ω Cen and NGC 2808 support the late hot flasher
  scenario, but the stars contain much less helium than expected and the
  predicted C, N enrichment could not be verified. <BR />Aims: We compare
  observed effective temperatures, surface gravities, and abundances of
  He, C, and N of blue hook and canonical extreme horizontal branch (EHB)
  star candidates to the predictions of the two scenarios. <BR />Methods:
  Moderately high resolution spectra of stars at the hot end of the
  blue HB in the globular cluster ω Cen were analysed for atmospheric
  parameters and abundances using LTE and non-LTE model atmospheres. <BR
  />Results: In the temperature range 30 000 K to 50 000 K we find that
  35% of our stars are helium-poor (log{{n_He}/{n_H}} &lt; -2), 51% have
  solar helium abundance within a factor of 3 (-1.5 ⪉ log{{n_He}/{n_H}}
  ⪉ -0.5) and 14% are helium-rich (log{{n_He}/{n_H}}} &gt; -0.4). We
  also find carbon enrichment strongly correlated with helium enrichment,
  with a maximum carbon enrichment of 3% by mass. <BR />Conclusions: At
  least 14% of the hottest HB stars in ω Cen show helium abundances well
  above the highest predictions from the helium enrichment scenario (Y =
  0.42 corresponding to log{{n_He}/{n_H}} ≈ -0.74). In addition, the
  most helium-rich stars show strong carbon enrichment, as predicted by
  the late hot flasher scenario. We conclude that the helium-rich HB stars
  in ω Cen cannot be explained solely by the helium-enrichment scenario
  invoked to explain the blue main sequence. <P />Based on observations
  <P />with the ESO Very Large Telescope at Paranal Observatory, Chile
  <P />(proposal IDs 075.D-0280(A) and 077.D-0021(A)).

Title: XMM-Newton Observations of Soft X-Ray Selected Magnetic CVs
Authors: Traulsen, Iris; Reinsch, Klaus; Dreizler, Stefan
Bibcode: 2007AN....328..712T
Altcode:
  No abstract at ADS

Title: SDSS DR4: Hot White Dwarf Luminosity Function
Authors: Krzesinski, J.; Kleinman, S. J.; Nitta, A.; Hügelmeyer,
   S. D.; Dreizler, S.
Bibcode: 2007ASPC..372...65K
Altcode:
  A large, nearly complete, magnitude-limited,
  spectroscopically-identified sample of hot white dwarf stars presented
  in the Sloan Digital Sky Survey (SDSS) Data Release 4 White Dwarf
  Catalog tep{p8_eis06} allowed us to construct the hot end of a SDSS
  white dwarf luminosity function (LF). The LF covers an approximate
  temperature range of 23,000 K to 100,000 K and is based on the distances
  and absolute bolometric magnitudes determined from stellar models. The
  sample is dominated by DA type white dwarfs, but it also contains DB,
  DAO, DO and PG 1159 type stars. We present our new LF, compare it to
  previous work tep{p8_har06}, and comment on sample completeness.

Title: X-Ray Spectroscopy and Photometry of the Accreting White
    Dwarf in AI Tri
Authors: Traulsen, I.; Reinsch, K.; Dreizler, S.; Schwarz, R.
Bibcode: 2007ASPC..372..553T
Altcode:
  Based on recent X-ray observations with the XMM-Newton satellite, we
  present first results of our spectroscopic and photometric analysis of
  the accretion region on the white dwarf in the long-period magnetic
  cataclysmic variable AI Tri. Our XMM-Newton observation covers for
  the first time uninterruptedly a complete binary orbital period. The
  shape of the X-ray light curve is highly variable with strong flares,
  occurring mainly in the soft energy range over about 70% of the binary
  orbit. Weaker hard X-ray emission is visible nearly all the time. The
  ultraviolet light curve, obtained in the UVM2 filter at an effective
  wavelength of 231 nm, has a similar shape but higher amplitude than
  the optical and near UV light curves reported during high states of
  accretion. The X-ray spectrum is dominated by soft X-ray emission which
  can be described in good approximation by a mildly absorbed blackbody
  component with kT<SUB>bb</SUB> = 36.8<SUP>+1.8</SUP><SUB>-1.4</SUB>
  {eV} and N<SUB>H</SUB> = 3.08<SUP>+0.51</SUP><SUB>-0.42</SUB> \cdot
  10<SUP>20</SUP> {cm}<SUP>-2</SUP>. In addition, weak emission from a
  thermal plasma is present and iron Kα at 6.4 keV and iron L emission
  around 0.9 keV can be identified.

Title: Abell 43 and PG 0122+200: a Look at the Beginning and at the
    End of the PG 1159 Instability Strip
Authors: Vauclair, G.; Solheim, J. -E.; Fu, J. -N.; Chevreton, M.;
   Dolez, N.; O'Brien, M. S.; Mukadam, A. S.; Kim, S. -L.; Park, B. -G.;
   Handler, G.; Medupe, R.; Wood, M.; González Perez, J.; Hashimoto,
   O.; Kinugasa, K.; Taguchi, H.; Kambe, E.; Dobrovolskas, V.; Provencal,
   J. L.; Dreizler, S.; Schuh, S.; Leibowitz, E. M.; Lipkin, Y.; Zhang,
   X. -B.; Paparo, M.; Szeidl, B.; Virághalmy, G.; Zsuffa, D.
Bibcode: 2007ASPC..372..641V
Altcode:
  While Abell 43 is entering the PG 1159 instability strip, in fact
  as an "hybrid-PG 1159" nucleus of a planetary nebula, PG 0122+200
  presently defines its red edge. So these two stars define the limits
  of the instability strip along the evolutionary sequence from the
  planetary nebula nuclei to the pre-white dwarf PG 1159 stars. We
  describe the new observations that have been obtained recently on
  these two extreme PG 1159 pulsators. Abell 43, the second discovered
  "hybrid-PG 1159" pulsator after HS 2324+3944, is a multi-periodic low
  amplitude pulsator with the longest period observed so far in PG 1159
  pulsators. As it shows amplitude variations, follow-up observations
  are needed to obtain a sufficient number of frequencies to start an
  asteroseismological analysis. We summarize the status of the presently
  available data. On PG 0122+200, new observations were obtained in
  2001 and 2002. Together with previous data, they allow us to detect 23
  frequencies, including seven triplets and two single frequencies. We
  interpret the triplets as ℓ=1 modes split by rotation and confirm an
  average rotation period of 1.55 days. From the up-dated average period
  spacing of 22.9 s, we derive a mass of 0.59 ± 0.02 M<SUB>⊙</SUB>,
  in better agreement with the spectroscopically derived mass than from
  previous estimates, and a luminosity log(L/L<SUB>⊙</SUB>)= 1.3 ±
  0.5. The uncertainty on the luminosity is dominated by the poorly
  determined surface gravity. We discuss the impact of that new mass
  determination on the predicted neutrino luminosity.

Title: Spectral Analyses of 16 DAO White Dwarfs from the Sloan
    Digital Sky Survey
Authors: Hügelmeyer, S. D.; Dreizler, S.; Rauch, T.; Krzesiński, J.
Bibcode: 2007ASPC..372..187H
Altcode: 2006astro.ph.10744H
  We present a spectral analysis of 16 DAO from the Sloan Digital Sky
  Survey Data Release 4. With our NLTE H+He model grid, we derived
  photospheric parameters for these objects. We compare our new results
  to literature values and divide the DAOs into two distinct groups:
  post-AGB and EHB progenitors.

Title: Observational Constraints on the Evolutionary Connection
    between PG 1159 Stars and DO White Dwarfs
Authors: Hügelmeyer, S. D.; Dreizler, S.; Werner, K.; Krzesinski,
   J.; Nitta, A.; Kleinman, S. J.
Bibcode: 2007ASPC..372..249H
Altcode: 2006astro.ph.10746H
  The Sloan Digital Sky Survey has provided spectra of a large number
  of new PG 1159 stars and DO white dwarfs. This increase in known hot
  H-deficient compact objects significantly improves the statistics and
  helps to investigate late stages of stellar evolution. We have finished
  our analyses of nine PG 1159 stars and 23 DO white dwarfs by means
  of detailed NLTE model atmospheres. From the optical SDSS spectra,
  effective temperatures, surface gravities, and element abundances are
  derived by using our new automated χ^2--fitting in order to place the
  observed objects in an evolutionary context. Especially the connection
  between PG 1159 stars and DO white dwarfs has been investigated.

Title: BMBF funded projects at Göttingen
Authors: Kollatschny, Wolfram; Hofmann, Denni; Dreizler, Stefan;
   Nicklas, Harald; Zetzl, Matthias; Köhler, Christof
Bibcode: 2007AN....328..710K
Altcode:
  No abstract at ADS

Title: Spectral Analysis and Constraints on the Nature of the
    Ultra-Compact Binary RX J0806.3+1527
Authors: Reinsch, K.; Steiper, J.; Dreizler, S.
Bibcode: 2007ASPC..372..419R
Altcode:
  RX J0806.3+1527 has been discovered as a luminous soft X-ray
  source during the ROSAT All-Sky Survey and is suspected to be a
  double-degenerate white dwarf binary with the shortest known orbital
  period of 321 s. We have performed the first NLTE analysis of its
  optical spectrum which consists of a blue continuum with weak emission
  lines superimposed. Using a grid of hot white dwarf atmospheres
  including illumination effects we have derived an abundance ratio
  (He/H) ≈ 0.1 (by number) and a comparably low surface gravity log{g}
  = 6 of the irradiated system component. The observed flux implies
  a distance d ≈ 2.0 kpc to the system. Our findings provide new
  constrains for the different models proposed for the nature of this
  peculiar binary. The donor must have about solar composition. If line
  emission arises from its irradiated side it could be either a low-mass
  white dwarf or a substellar object. Alternatively, line emission could
  arise from an accretion column standing several white dwarf radii above
  the photosphere of the accretor. Such conditions are encountered in
  systems with comparably low field strengths and high mass-flow rates.

Title: Investigation of transit-selected exoplanet candidates from
    the MACHO survey
Authors: Hügelmeyer, S. D.; Dreizler, S.; Homeier, D.; Reiners, A.
Bibcode: 2007A&A...469.1163H
Altcode: 2007arXiv0704.1366H
  Context: Planets outside our solar system transiting their host
  star, i.e. those with an orbital inclination near 90°, are
  of special interest to derive physical properties of extrasolar
  planets. With the knowledge of the host star's physical parameters,
  the planetary radius can be determined. Combined with spectroscopic
  observations the mass and therefore the density can be derived from
  Doppler-measurements. Depending on the brightness of the host star,
  additional information, e.g. about the spin-orbit alignment between the
  host star and planetary orbit, can be obtained. <BR />Aims: The last few
  years have witnessed a growing success of transit surveys. Among other
  surveys, the MACHO project provided nine potential transiting planets,
  several of them with relatively bright parent stars. The photometric
  signature of a transit event is, however, insufficient to confirm the
  planetary nature of the faint companion. The aim of this paper therefore
  is a determination of the spectroscopic parameters of the host stars as
  well as a dynamical mass determination through Doppler-measurements. <BR
  />Methods: We obtained follow-up high-resolution spectra for five stars
  selected from the MACHO sample, which are consistent with transits
  of low-luminosity objects. Radial velocities were determined by means
  of cross-correlation with model spectra. The MACHO light-curves were
  compared to simulations based on the physical parameters of the system
  derived from the radial velocities and spectral analyses. <BR />Results:
  We show that all transit light-curves of the exoplanet candidates
  analysed in this work can be explained by eclipses of stellar objects,
  hence none of the five transiting objects is a planet. <P />Based on
  observations made with ESO Telescopes <P />at the La Silla or Paranal
  Observatories under programme ID <P />075.C-0526(A).

Title: Analyzing <ASTROBJ>SN 2003Z</ASTROBJ> with PHOENIX
Authors: Knop, S.; Hauschildt, P. H.; Baron, E.; Dreizler, S.
Bibcode: 2007A&A...469.1077K
Altcode: 2009arXiv0902.1867K
  Aims:We present synthetic spectra around maximum for the type
  II supernova SN 2003Z, which was first detected on January 29.7
  2003. Comparison with observed spectra aim at the determination of
  physical parameters for SN 2003Z. <BR />Methods: Synthetic spectra
  are calculated with our stellar atmosphere code PHOENIX. It solves the
  special relativistic equation of radiative transfer, including large
  NLTE-calculations and line blanketing by design, in 1-dimensional
  spherical symmetry. The observed spectra were obtained at the 3.5
  m telescope at Calar Alto. The TWIN instrument was used so that a
  spectral range from about 3600 to 7500 Å was covered. The spectra
  were taken on Feb. 4, 5, 9, and 11, 2003. <BR />Results: The physical
  parameters of the models give the luminosities, a range of possible
  velocity profiles for the SN, an estimate of the colour excess, and
  the observed metalicity. <P />Based on observations collected at the
  Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated
  jointly by the Max-Planck Institut für Astronomie and the Instituto
  de Astrofísica de Andalucía (CSIC).

Title: X-Ray Spectroscopy and Photometry of the long-period Polar
    AI Tri with XMM-Newton
Authors: Traulsen, I.; Reinsch, K.; Dreizler, S.
Bibcode: 2007xnnd.confP...4T
Altcode:
  No abstract at ADS

Title: MONET, HET and SALT and asteroseismological observations and
    theory in Göttingen
Authors: Schuh, S.; Hessman, F. V.; Dreizler, S.; Kollatschny, W.;
   Glatzel, W.
Bibcode: 2007CoAst.150..317S
Altcode:
  The Göttingen stellar astrophysics group, headed by Stefan Dreizler,
  conducts research on extrasolar planets and their host stars,
  on lower-main sequence stars, and on evolved compact objects, in
  particular hot white dwarfs (including PG 1159 objects, magnetic
  WDs and cataclysmic variables), and subdwarf B stars. In addition to
  sophisticated NLTE spectral analyses of these stars, which draw on
  the extensive stellar atmosphere modelling experience of the group,
  we actively develop and apply a variety of photometric monitoring
  and time-resolved spectroscopic techniques to address time-dependent
  phenomena. With the new instrumentational developments described
  below, we plan to continue the study of variable white dwarfs (GW Vir,
  DB and ZZ Ceti variables) and in particular sdB EC 14026 and PG 1617
  pulsators which already constitute a main focus, partly within the Whole
  Earth Telescope (WET/DARC), http://www.physics.udel.edu/~jlp/darc/)
  collaboration, on a new level. Additional interest is directed towards
  strange mode instabilities in Wolf Rayet stars.

Title: Asteroseismology of the PG 1159 star PG 0122+200
Authors: Fu, J. -N.; Vauclair, G.; Solheim, J. -E.; Chevreton, M.;
   Dolez, N.; O'Brien, M. S.; Kim, S. -L.; Park, B. -G.; Handler, G.;
   Medupe, R.; Wood, M.; Gonzalez Perez, J.; Hashimoto, O.; Kinugasa,
   K.; Taguchi, H.; Kambe, E.; Provencal, J.; Dreizler, S.; Schuh, S.;
   Leibowitz, E.; Lipkin, Y.; Zhang, X. -B.; Paparo, M.; Szeidl, B.;
   Virághalmy, G.; Zsuffa, D.
Bibcode: 2007A&A...467..237F
Altcode:
  Context: The variable pre-white dwarf PG 1159 stars (GW Vir) are
  g-mode non-radial pulsators. Asteroseismology puts strong constraints
  on their global parameters and internal structure. PG 0122+200 defines
  the red edge of the instability strip and its evolutionary timescale
  is predicted to be dominated by neutrino emission. Its study offers
  the opportunity to better understand the instability mechanism and to
  validate the physics of the neutrino production in dense plasma. <BR
  />Aims: To achieve such a goal requires determining precisely its
  fundamental parameters. This is the goal of this paper. <BR />Methods:
  We present new multi-site photometric observations obtained in 2001
  and 2002. Together with previous data, they allow us to detect
  23 frequencies, composed of 7 triplets and 2 single frequencies,
  which are used to constrain its internal structure and derive its
  fundamental parameters. <BR />Results: All the observed frequencies
  correspond to ℓ=1 g-modes. The period distribution shows a signature
  of mode trapping from which we constrain the He-rich envelope mass
  fraction to be -6.0≤ log(q<SUB>y</SUB>) ≤ -5.3. The comparison
  of the mode trapping amplitudes among GW Vir stars suggests that the
  mass-loss efficiency must decrease significantly below T_eff≤ 140
  kK. We measure an average period spacing of 22.9 s from which we
  derive a mass of 0.59±0.02 M<SUB>⊙</SUB>. From the triplets we
  measure a mean rotational splitting of 3.74 μHz and a rotational
  period of 1.55 days. We derive an upper limit to the magnetic field
  of B≤4×10<SUP>3</SUP> G. The luminosity (log L/L<SUB>⊙</SUB> =
  1.3±0.5) and the distance (D = 0.7^+1.0_-0.4 kpc) are only weakly
  constrained due to the large uncertainty on the spectroscopically
  derived surface gravity and the absence of a measured parallax. <BR
  />Conclusions: From the asteroseismic mass, the ratio of the
  neutrino luminosity on the photon luminosity is 1.6±0.2 confirming
  that the PG 0122+200 evolutionary time scale should be dominated by
  neutrino cooling. A measurement of dot{P} for the largest amplitude
  untrapped modes should verify this prediction. <P />Based on data
  obtained at the Haute-Provence Observatory, INSU/CNRS, France; the
  Nordic Optical Telescope, La Palma, Spain; the Xinglong station of
  National Astronomical Observatories, China; the Bohyunsan Observatory,
  South-Korea; the Gunma Astrophysical Observatory, Japan; the Teide
  Observatory, Tenerife, Spain; the Calar Alto Observatory, Spain; the
  Kitt Peak National Observatory, Arizona, USA; the McDonald Observatory,
  Texas, USA; the South Africa Astronomical Observatory, South Africa;
  the Wise Observatory, Israel and the Piszkéstető Observatory, Hungary.

Title: Spectral types of planetary host star candidates from OGLE III
Authors: Dreizler, S.; Schuh, S.; Homeier, D.
Bibcode: 2007A&A...464..367D
Altcode: 2007astro.ph..1718D
  Context: The Optical Gravitational Lensing Experiment project has
  recently provided the OGLE III list of low-luminosity object transits
  from campaigns #3 and #4, reporting 40 new objects exhibiting the
  low-amplitude photometric eclipses expected for exoplanets. Compared
  to previous OGLE targets, these OGLE III candidates have been
  more restrictively selected and may contain low-mass planets. <BR
  />Aims: We have secured follow-up low-resolution spectroscopy for 28
  candidates out of this list (and one from the OGLE Carina fields)
  to obtain an independent characterization of the primary stars by
  spectral classification and thus better constrain the parameters of
  their companions. <BR />Methods: We fed the constraints from these
  results back into an improved light curve solution. Together with the
  radius ratios from the transit measurements, we derived the radii of
  the low-luminosity companions. This allows us to examine the possible
  sub-stellar nature of these objects. <BR />Results: Sixteen of the
  companions can be clearly identified as low-mass stars orbiting a main
  sequence primary, while 10 more objects are likely to have red giant
  primaries and therefore also host a stellar companion; 3 possibly
  have a sub-stellar nature (R≤ 0.15 R_⊙). <BR />Conclusions: .The
  planetary nature of these objects should therefore be confirmed by
  dynamical mass determinations.

Title: Hot subdwarfs from the ESO supernova Ia progenitor
    survey. II. Atmospheric parameters of subdwarf O stars
Authors: Stroeer, A.; Heber, U.; Lisker, T.; Napiwotzki, R.; Dreizler,
   S.; Christlieb, N.; Reimers, D.
Bibcode: 2007A&A...462..269S
Altcode: 2006astro.ph..9718S
  Aims: We address the origin and evolutionary status of hot subdwarf
  stars by studying the optical spectral properties of 58 subdwarf O
  (sdO) stars. Combining them with the results of our previously studied
  subdwarf B (sdB) stars, we aim at investigating possible evolutionary
  links. <BR />Methods: We analyse high-resolution (R &gt; 18 000),
  high-quality optical spectra of sdO stars obtained with the ESO
  VLT UVES echelle spectrograph in the course of the ESO Supernova Ia
  Progenitor Survey (SPY). Effective temperatures, surface gravities,
  and photospheric helium abundances are determined simultaneously by
  fitting the profiles of hydrogen and helium lines using dedicated
  synthetic spectra calculated from an extensive grid of NLTE model
  atmospheres. <BR />Results: We find spectroscopic or photometric
  evidence for cool companions to eight sdO stars, as well as a binary
  consisting of two sdO stars. A clear correlation between helium
  abundances and the presence of carbon and/or nitrogen lines is found:
  below solar helium abundance, no sdO star shows C or N lines. In
  contrast, C and/or N lines are present in the spectra of all sdO
  stars with supersolar helium abundance. We thus use the solar helium
  abundance to divide our sample into helium-deficient and helium-enriched
  sdO stars. While helium-deficient sdO stars are scattered in a wide
  range of the {T_eff}-log(g)-diagram, most of the helium-enriched sdO
  stars cluster in a narrow region at temperatures between 40 000 and 50
  000 K and gravities between log g=5.5 and 6.0. <BR />Conclusions: . An
  evolutionary link between sdB stars and sdO stars appears plausible only
  for the helium-deficient sdO stars. They probably have evolved away from
  the extreme horizontal branch; i.e., they are the likely successors to
  sdB stars. In contrast, the atmospheric properties of helium-enriched
  sdO stars cannot be explained with canonical single-star evolutionary
  models. Alternative scenarios for both single-star (late hot flasher)
  and binary evolution (white-dwarf merger; post-RGB evolution) fail
  to reproduce the observed properties of helium-enriched sdO stars
  in detail. While we regard the post-RGB scenario as inappropriate,
  the white-dwarf merger and the late hot-flasher scenarios remain
  viable to explain the origin of helium-enriched sdO stars. <P />Based
  <P />on observations collected at the Paranal Observatory of the
  European <P />Southern Observatory for programme No. 165.H-0588(A)
  and 167.D-0407(A).

Title: Spectral analyses of eighteen hot H-deficient (pre-) white
    dwarfs from the Sloan Digital Sky Survey Data Release 4
Authors: Hügelmeyer, S. D.; Dreizler, S.; Homeier, D.; Krzesiński,
   J.; Werner, K.; Nitta, A.; Kleinman, S. J.
Bibcode: 2006A&A...454..617H
Altcode: 2006astro.ph..5551H
  Context: .The Sloan Digital Sky Survey Data Release 4 has provided
  spectra of several new PG 1159 stars and DO white dwarfs. This increase
  in known hot H-deficient compact objects significantly improves the
  statistics and helps to investigate late stages of stellar evolution.<BR
  /> Aims: .From the optical SDSS spectra, effective temperatures and
  surface gravities are derived in order to place the observed objects
  in an evolutionary context. Especially the connection between PG 1159
  stars and DO white dwarfs shall be investigated.<BR /> Methods: .Using
  our non-LTE model atmospheres and applying χ<SUP>2</SUP>-fitting
  techniques, we determine stellar parameters and their errors. We
  derive total stellar masses for the DO white dwarfs using model
  evolutionary tracks.<BR /> Results: .We confirm three PG 1159 stars,
  with one showing ultra-high excitation ion features, and one sdO which
  we originally classified as a PG 1159 star. Additionally, we re-analysed
  the known PG 1159 star, PG 1424+535, with our new models. Furthermore,
  we present the first spectral analyses of thirteen DO white dwarfs,
  three of which show M-star features in their spectra, while two display
  ultra-high excitation ion features.<BR />

Title: The D/H Ratio towards PG 0038+199
Authors: Williger, G. M.; Oliveira, C.; Hébrard, G.; Dupuis, J.;
   Dreizler, S.
Bibcode: 2006ASPC..348...97W
Altcode:
  We determine the D/H ratio in the interstellar medium toward the
  DO white dwarf PG 0038+199 using spectra from the Far Ultraviolet
  Spectroscopic Explorer (FUSE), with ground-based support from Keck H
  IRES. We employ curve of growth, apparent optical depth and profile
  fitting techniques to measure column densities and limits of many
  other species which allow us to determine related ratios such as
  D/O, D/N and the H<SUB>2</SUB> fraction. We estimate a distance to PG
  0038+199 of 297<SUP>+164</SUP><SUB>-104</SUB> pc (1σ). We find column
  densities log N(H I) = 20.41± 0.08, log N(D I) = 15.75± 0.08 and log
  N(H<SUB>2</SUB>) = 19.33± 0.04, yielding a molecular hydrogen fraction
  of 14± 2% (all 2σ errors). [D I + HD]/[H I + 2H<SUB>2</SUB>] toward
  PG 0038+199 is 1.91<SUP>+0.52</SUP><SUB>-0.42</SUB>× 10<SUP>-5</SUP>
  (2σ). There is no evidence of component structure on the scale of Δ v
  &gt; 8 km s<SUP>-1</SUP> based on Na I, but there is marginal evidence
  for structure on smaller scales. The D/H value is high compared to the
  majority of recent D/H measurements, but consistent with the values
  for two other measurements at similar distances. D/O is in agreement
  with other distant measurements. The scatter in D/H values beyond ∼
  100 pc remains a challenge for Galactic chemical evolution.

Title: Probing unexplored territories with MUSE: a second generation
    instrument for the VLT
Authors: Bacon, R.; Bauer, S.; Boehm, P.; Boudon, D.; Brau-Nogué, S.;
   Caillier, P.; Capoani, L.; Carollo, C. M.; Champavert, N.; Contini,
   T.; Daguisé, E.; Dallé, D.; Delabre, B.; Devriendt, J.; Dreizler,
   S.; Dubois, J.; Dupieux, M.; Dupin, J. P.; Emsellem, E.; Ferruit, P.;
   Franx, M.; Gallou, G.; Gerssen, J.; Guiderdoni, B.; Hahn, T.; Hofmann,
   D.; Jarno, A.; Kelz, A.; Koehler, C.; Kollatschny, W.; Kosmalski,
   J.; Laurent, F.; Lilly, S. J.; Lizon, J.; Loupias, M.; Lynn, S.;
   Manescau, A.; McDermid, R. M.; Monstein, C.; Nicklas, H.; Parès, L.;
   Pasquini, L.; Pécontal-Rousset, A.; Pécontal, E.; Pello, R.; Petit,
   C.; Picat, J. -P.; Popow, E.; Quirrenbach, A.; Reiss, R.; Renault,
   E.; Roth, M.; Schaye, J.; Soucail, G.; Steinmetz, M.; Stroebele, S.;
   Stuik, R.; Weilbacher, P.; Wozniak, H.; de Zeeuw, P. T.
Bibcode: 2006SPIE.6269E..0JB
Altcode: 2006astro.ph..6329B; 2006SPIE.6269E..17B
  The Multi Unit Spectroscopic Explorer (MUSE) is a second-generation
  VLT panoramic integral-field spectrograph under preliminary design
  study. MUSE has a field of 1x1 arcmin<SUP>2</SUP> sampled at 0.2x0.2
  arcsec<SUP>2</SUP> and is assisted by the VLT ground layer adaptive
  optics ESO facility using four laser guide stars. The simultaneous
  spectral range is 0.465-0.93 μm, at a resolution of R~3000. MUSE
  couples the discovery potential of a large imaging device to the
  measuring capabilities of a high-quality spectrograph, while taking
  advantage of the increased spatial resolution provided by adaptive
  optics. This makes MUSE a unique and tremendously powerful instrument
  for discovering and characterizing objects that lie beyond the reach
  of even the deepest imaging surveys. MUSE has also a high spatial
  resolution mode with 7.5x7.5 arcsec<SUP>2</SUP> field of view sampled at
  25 milli-arcsec. In this mode MUSE should be able to obtain diffraction
  limited data-cubes in the 0.6-0.93 μm wavelength range. Although the
  MUSE design has been optimized for the study of galaxy formation and
  evolution, it has a wide range of possible applications; e.g. monitoring
  of outer planets atmosphere, environment of young stellar objects,
  super massive black holes and active nuclei in nearby galaxies or
  massive spectroscopic surveys of stellar fields in the Milky Way and
  nearby galaxies.

Title: Probing Unexplored Territories with MUSE: a Second-Generation
    Instrument for the VLT
Authors: Bacon, Roland; Bauer, Svend; Böhm, Petra; Boudon, Didier;
   Brau-Nogue, Sylvie; Caillier, Patrick; Capoani, Lionel; Carollo,
   C. Marcella; Champavert, Nicolas; Contini, Thierry; Daguise, Eric;
   Dalle, Didier; Delabre, Bernard; Devriendt, Julien; Dreizler, Stefan;
   Dubois, Jean-Pierre; Dupieux, Michel; Dupin, Jean-Pierre; Emsellem,
   Eric; Ferruit, Pierre; Franx, Marijn; Gallou, Gérard; Gerssen, Joris;
   Guiderdoni, Bruno; Hahn, Thomas; Hofmann, Denni; Jarno, Aurélien;
   Kelz, Andreas; Koehler, Christof; Kollatschny, Wolfram; Kosmalski,
   Johan; Laurent, Florence; Lilly, Simon J.; Lizon, Jean-Louis; Loupias,
   Magali; Lynn, Stéphanie; Manescau, Antonio; McDermid, Richard M.;
   Monstein, Christian; Nicklas, Harals; Perès, Laurent; Pasquini,
   Luca; Pécontal, Emmanuel; Pécontal-Rousset, Arlette; Pello, Roser;
   Petit, Chantal; Picat, Jean-Pierre; Popow, Emil; Quirrenbach, Andreas;
   Reiss, Roland; Renault, Edgar; Roth, Martin; Schaye, Joop; Soucail,
   Geneviève; Steinmetz, Matthias; Ströbele, Stefan; Stuik, Remko;
   Weilbacher, Peter; Wozniak, Herve; de Zeeuw, P. Tim
Bibcode: 2006Msngr.124....5B
Altcode:
  The Multi Unit Spectroscopic Explorer (MUSE) is a second-generation
  VLT panoramic integral-field spectrograph presently under preliminary
  design study. MUSE has a field of 1 × 1 arcmin2 sampled at 0.2 ×
  0.2 arcsec2 and is assisted by the VLT ground layer adaptive optics
  ESO facility using four laser guide stars. The simultaneous spectral
  range is 0.465-0.93 μm, at a resolution of R ~ 3000. MUSE couples
  the discovery potential of a large imaging device to the measuring
  capabilities of a high-quality spectrograph, while taking advantage of
  the increased spatial resolution provided by adaptive optics. MUSE has
  also a high spatial resolution mode with 7.5 × 7.5 arcsec2 field of
  view sampled at 25 milli-arcsec. In this mode MUSE should be able to
  obtain diffraction-limited data cubes in the 0.6-0.93 μm wavelength
  range.

Title: VLT spectroscopy and non-LTE modeling of the C/O-dominated
    accretion disks in two ultracompact X-ray binaries
Authors: Werner, K.; Nagel, T.; Rauch, T.; Hammer, N. J.; Dreizler, S.
Bibcode: 2006A&A...450..725W
Altcode: 2006astro.ph..1546W
  Aims.We present new medium-resolution high-S/N optical spectra of
  the ultracompact low-mass X-ray binaries 4U 0614+091 and 4U 1626-67,
  taken with the ESO Very Large Telescope. They are pure emission line
  spectra and the lines are identified as due to CII-IV and OII-III.<BR
  /> Methods: .Line identification is corroborated by first results from
  modeling the disk spectra with detailed non-LTE radiation transfer
  calculations. Hydrogen and helium lines are lacking in the observed
  spectra.<BR /> Results: .Our models confirm the deficiency of H and He
  in the disks. The lack of neon lines suggests an Ne abundance of less
  than about 10 percent (by mass), however, this result is uncertain due
  to possible shortcomings in the model atom. These findings suggest
  that the donor stars are eroded cores of C/O white dwarfs with no
  excessive neon overabundance. This would contradict earlier claims of Ne
  enrichment concluded from X-ray observations of circumbinary material,
  which was explained by crystallization and fractionation of the white
  dwarf core.<BR />

Title: SDSS J212531.92-010745.9 - the first definite PG 1159 close
    binary system
Authors: Nagel, T.; Schuh, S.; Kusterer, D. -J.; Stahn, T.;
   Hügelmeyer, S. D.; Dreizler, S.; Gänsicke, B. T.; Schreiber, M. R.
Bibcode: 2006A&A...448L..25N
Altcode: 2006astro.ph..1512N
  Aims.The archival spectrum of SDSS J212531.92-010745.9 shows not
  only the typical signature of a PG 1159 star, but also indicates the
  presence of a companion. Our aim was the proof of the binary nature
  of this object and the determination of its orbital period.Methods.We
  performed time-series photometry of SDSS J212531.92-010745.9. We
  observed the object during 10 nights, spread over one month, with
  the Tübingen 80 cm and the Göttingen 50 cm telescopes. We fitted
  the observed light curve with a sine and simulated the light curve of
  this system with the nightfall program. Furthermore, we compared the
  spectrum of SDSS J212531.92-010745.9 with NLTE models, the results
  of which also constrain the light curve solution. Results.An orbital
  period of 6.95616(33) h with an amplitude of 0.354(3) mag is derived
  from our observations. A pulsation period could not be detected. For
  the PG 1159 star we found, as preliminary results from comparison
  with our NLTE models, T<SUB>eff</SUB> ~ 90 000 K, log g ~ 7.60, and
  the abundance ratio C/He ~ 0.05 by number fraction. For the companion
  we obtained with a mean radius of 0.4 ± 0.1~R<SUB>⊙</SUB>, a mass
  of 0.4 ± 0.1~M<SUB>⊙</SUB>, and a temperature of 8200 K on the
  irradiated side, good agreement between the observed light curve and
  the nightfall simulation, but we do not regard those values as final.

Title: Giant Transiting Planets Observations GITPO
Authors: Afonso, C.; Henning, Th.; Weldrake, D.; Mazeh, T.; Dreizler,
   S.
Bibcode: 2006dies.conf...79A
Altcode: 2006IAUCo.200...79A
  The search for extrasolar planets is nowadays one of the most promising
  science drivers in Astronomy. The radial velocity technique proved
  to be successful in planet hunting, harvesting more than a hundred
  planets to date. In these last recent years, the transit method has
  come to fruition, with the detection of seven Jupiter-mass extrasolar
  transiting planets in close-in orbits ({ AU). Currently, the radius of
  planets can only be determined from transiting planets, representing
  the principal motivation and strength of this technique. The MPIA is
  presently building the Large Area Imager (LAIWO) for the 1m telescope
  in the Wise Observatory, Israel. LAIWO will have a field of view of
  one square degree. An intensive search for extra-solar planets will
  be performed with the 1m Wise telescope, together with the 1.2m MONET
  telescope in Texas. We will monitor three fields at a given time during
  three years and more than 200 nights per year. We expect several dozens
  of extra-solar planets.

Title: The Msst Campaign: 4 M Spectroscopy of PG 1605+072
Authors: Jeffery, C. S.; Heber, U.; Dreizler, S.; O'Toole, S. J.;
   Schuh, S. L.; Woolf, V. M.; Falter, S.; Nitta, A.; Kleinman, S.;
   Krzesinski, J.; Billères, M.
Bibcode: 2006BaltA..15..321J
Altcode: 2006OAst...15..321J
  The MultiSite Spectroscopic Telescope (MSST) campaign aimed to provide
  a detailed view of the short-period pulsating subdwarf B star PG 1605+
  072. We present results from the part of the campaign undertaken on
  4 m telescopes in 2002 May and June.

Title: Exciting new features in the frequency spectrum of the EC 14026
    star HS 0702+6043. Simultaneous g-modes and p-modes in a sdB pulsator
Authors: Schuh, S.; Huber, J.; Dreizler, S.; Green, E. M.; Stahn,
   T.; Randall, S.; Husser, T. -O.; Heber, U.; O'Toole, S.; Fontaine, G.
Bibcode: 2006MmSAI..77..480S
Altcode: 2005astro.ph.10832S
  The discovery of a long-period g-mode oscillation in the previously
  known short-period p-mode sdB pulsator HS 0702+6043 makes this star an
  extraordinary object, unique as a member of the family of sdB pulsators,
  and one of the very few known pulsating stars overall exhibiting excited
  modes along both the acoustic and gravity branches of the nonradial
  pulsation spectrum. Because p-modes and g-modes probe different regions
  of a pulsating star, HS 0702+6043 holds a tremendous potential for
  asteroseismological investigations. We present preliminary results
  from the first extended campaign on this object.

Title: Subluminous O Stars
Authors: Heber, U.; Hirsch, H.; Ströer, A.; O'Toole, S.; Haas, S.;
   Dreizler, S.
Bibcode: 2006BaltA..15...91H
Altcode: 2006OAst...15...91H
  We report results of spectral analyses of sdO stars selected from
  the Supernova Ia Progenitor Survey, the Hamburg Quasar Survey and
  the Sloan Digital Sky Survey and based on state-of-the-art NLTE model
  atmospheres. By combining the sdO with the sdB samples we discuss trends
  of the atmospheric parameters in order to search for evidence for
  possible evolutionary linkage. The He-sdO stars are found to cluster
  near Teff = 45 000 K, log g = 5.5, whereas the number of sdO stars
  in this area is very small. The ``cooler'' sdO stars seem to form an
  extension to the sdB sequences. A couple of sdO stars are obviously
  evolved from the extended horizontal branch and reach temperatures
  as high as 80 000 K. We conjecture that the He-sdO stars and sdO/sdB
  stars have a different evolutionary origin. This is corroborated by
  the much lower binary frequency of the former. Strong enrichments
  of iron group elements are discovered for hydrogen-rich sdO stars
  as well as for sdB stars from high resolution UV spectra and have
  severe implications for the temperature scale. We finally highlight
  the discovery of a hyper-velocity He-sdO star with a radial velocity
  of 708 kms unbound to the Galaxy.

Title: An Approach to a Stability Analysis of a SDO Star
Authors: Rodríguez-López, C.; Moya, A.; Garrido, R.; MacDonald,
   J.; Ulla, A.; Dreizler, S.; Hügelmeyer, S. D.; Manteiga, M.
Bibcode: 2006BaltA..15..313R
Altcode: 2006OAst...15..313R
  A stability analysis of a structural model of an sdO star is
  presented. A non-adiabatic code of oscillations is used to search
  for modes in the frequency range 0.4 to 15 mHz. All of the computed
  modes were found to be stable. We draw attention, however, to three
  different stability regions.

Title: <ASTROBJ>HS 0702+6043</ASTROBJ>: a star showing both
    short-period p-mode and long-period g-mode oscillations
Authors: Schuh, S.; Huber, J.; Dreizler, S.; Heber, U.; O'Toole,
   S. J.; Green, E. M.; Fontaine, G.
Bibcode: 2006A&A...445L..31S
Altcode: 2005astro.ph.10831S
  Context: .The hot subdwarf B star <ASTROBJ>HS 0702+6043</ASTROBJ>
  is known as a large-amplitude, short-period p-mode pulsator of the
  <ASTROBJ>EC 14026</ASTROBJ> type. Its atmospheric parameters place it
  at the common boundary between the empirical instability regions of
  the <ASTROBJ>EC 14026</ASTROBJ> variables and the typically cooler
  long-period g-mode pulsators of the <ASTROBJ>PG 1716</ASTROBJ>
  kind.<BR /> Aims: .We analyse and interpret the photometric
  variability of <ASTROBJ>HS 0702+6043</ASTROBJ> in order to explore
  its asteroseismological potential.<BR /> Methods: .We report on
  rapid wide band CCD photometric observations to follow up on and
  confirm the serendipitous discovery of multiperiodic long-period
  luminosity variations with typical time scales of ~1 h in <ASTROBJ>HS
  0702+6043</ASTROBJ>, in addition to the two previously known pulsations
  at 363 s and 383 s. In particular, we isolate a relatively low-amplitude
  (~4 mmag), long-period (3538±130 s) light variation.<BR /> Results:
  .We argue that the most likely origin for this luminosity variation is
  the presence of an excited g-mode pulsation. If confirmed, <ASTROBJ>HS
  0702+6043</ASTROBJ> would constitute a rare addition to the very select
  class of pulsating stars showing simultaneously parts of their pressure
  and gravity mode pulsation spectra. The asteroseismological potential of
  such stars is immense, and <ASTROBJ>HS 0702+6043</ASTROBJ> thus becomes
  a target of choice for future investigations. While our discovery
  appears consistent with the location of <ASTROBJ>HS 0702+6043</ASTROBJ>
  at the common boundary between the two families of pulsating sdB stars,
  it does challenge theory's current description of stability and driving
  mechanisms in pulsating B subdwarfs.<BR /> Conclusions: .

Title: Light and Heavy Metal Abundances in Hot Central Stars of
    Planetary Nebulae
Authors: Werner, Klaus; Hoffmann, Agnes I. D.; Jahn, Dorothee; Rauch,
   Thomas; Reiff, Elke; Traulsen, Iris; Kruk, Jeffrey W.; Dreizler, Stefan
Bibcode: 2005AIPC..804..129W
Altcode: 2005astro.ph..8108W
  We present new results from our spectral analyses of very hot central
  stars achieved since the last IAU Symposium on planetary nebulae held
  in Canberra 2001. The analyses are mainly based on UV and far-UV
  spectroscopy performed with the Hubble Space Telescope and the Far
  Ultraviolet Spectroscopic Explorer but also on ground-based observations
  performed at the Very Large Telescope and other observatories. We
  report on temperature, gravity, and abundance determinations for the
  CNO elements of hydrogen-rich central stars. In many hydrogen-deficient
  central stars (spectral type PG1159) we discovered particular neon
  and fluorine lines, which are observed for the very first time in
  any astrophysical object. Their analysis strongly confirms the idea
  that these stars exhibit intershell matter as a consequence of a late
  helium-shell flash.

Title: On the most metal-poor PN and its binary central star
Authors: Napiwotzki, R.; Tovmassian, G.; Richer, M. G.; Stasińska,
   G.; Peña, M.; Drechsel, H.; Dreizler, S.; Rauch, T.
Bibcode: 2005AIPC..804..173N
Altcode: 2005astro.ph..9801N
  PN G135.9+55.9 is the most metal-poor PN known in our Galaxy. The
  central star resides in a short-period binary system with a compact
  component, probably a white dwarf. We describe new observations, which
  allowed us to determine the orbital period. The lower limit for the
  combined mass of both stars is close to the Chandrasekhar limit for
  white dwarfs, making this binary a possible progenitor of a supernova
  type Ia. The binary system must have recently emerged from a common
  envelope phase.

Title: High-resolution extreme ultraviolet spectroscopy of G191-B2B:
    structure of the stellar photosphere and the surrounding interstellar
    medium
Authors: Barstow, M. A.; Cruddace, R. G.; Kowalski, M. P.; Bannister,
   N. P.; Yentis, D.; Lapington, J. S.; Tandy, J. A.; Hubeny, I.; Schuh,
   S.; Dreizler, S.; Barbee, T. W.
Bibcode: 2005MNRAS.362.1273B
Altcode: 2005MNRAS.tmp..749B
  We have continued our detailed analysis of the high-resolution (R=
  4000) spectroscopic observation of the DA white dwarf G191-B2B,
  obtained by the Joint Astrophysical Plasmadynamic Experiment (J-PEX)
  normal incidence sounding rocket-borne telescope, comparing the
  observed data with theoretical predictions for both homogeneous and
  stratified atmosphere structures. We find that the former models
  give the best agreement over the narrow waveband covered by J-PEX,
  in conflict with what is expected from previous studies of the lower
  resolution but broader wavelength coverage Extreme Ultraviolet Explorer
  spectra. We discuss the possible limitations of the atomic data and
  our understanding of the stellar atmospheres that might give rise to
  this inconsistency. In our earlier study, we obtained an unusually
  high ionization fraction for the ionized HeII present along the line
  of sight to the star. In the present paper, we obtain a better fit
  when we assume, as suggested by Space Telescope Imaging Spectrograph
  results, that this HeII resides in two separate components. When one
  of these is assigned to the local interstellar cloud, the implied He
  ionization fraction is consistent with measurements along other lines
  of sight. However, the resolving power and signal-to-noise available
  from the instrument configuration used in this first successful J-PEX
  flight are not sufficient to clearly identify and prove the existence
  of the two components.

Title: Spectral analyses of DO white dwarfs and PG 1159 stars from
    the Sloan Digital Sky Survey
Authors: Hügelmeyer, S. D.; Dreizler, S.; Werner, K.; Krzesiński,
   J.; Nitta, A.; Kleinman, S. J.
Bibcode: 2005A&A...442..309H
Altcode: 2005astro.ph..8101H
  We present a model atmosphere analysis of ten new DO white dwarfs and
  five new PG 1159 stars discovered in the Sloan Digital Sky Survey DR1,
  DR2 and DR3. This is a significant increase in the number of known
  DOs and PG 1159 stars. DO white dwarfs are situated on the white
  dwarf cooling sequence from the upper hot end (T_eff ≈ 120 000 K)
  down to the DB gap (T_eff ≈ 45 000 K). PG 1159 stars on the other
  hand feature effective temperatures which exceed T_eff = 65 000 K with
  an upper limit of T_eff = 200 000 K and are the proposed precursors
  of DO white dwarfs. Improved statistics are necessary to investigate
  the evolutionary link between these two types of stars. From optical
  SDSS spectra effective temperatures, surface gravities and element
  abundances are determined by means of non-LTE model atmospheres.

Title: The MultiSite Spectroscopic Telescope campaign: 2 m
    spectroscopy of the V361 Hya variable PG 1605+072
Authors: O'Toole, S. J.; Heber, U.; Jeffery, C. S.; Dreizler, S.;
   Schuh, S. L.; Woolf, V. M.; Falter, S.; Green, E. M.; For, B. -Q.;
   Hyde, E. A.; Kjeldsen, H.; Mauch, T.; White, B. A.
Bibcode: 2005A&A...440..667O
Altcode: 2005astro.ph..6722O
  We present results and analysis for the 2 m spectroscopic part of the
  MultiSite Spectroscopic Telescope (MSST) campaign undertaken in May/June
  2002. The goal of the project was to observe the pulsating subdwarf
  B star PG 1605+072 simultaneously in velocity and photometry and to
  resolve as many of the &gt;50 known modes as possible, which will allow
  a detailed asteroseismological analysis. We have obtained over 150 h
  of spectroscopy, leading to an unprecedented noise level of only 207
  m s<SUP>-1</SUP>. We report here the detection of 20 frequencies in
  velocity, with two more likely just below our detection threshold. In
  particular, we detect 6 linear combinations, making PG 1605+072
  only the second star known to show such frequencies in velocity. We
  investigate the phases of these combinations and their parent modes
  and find relationships between them that cannot be easily understood
  based on current theory. These observations, when combined with our
  simultaneous photometry, should allow asteroseismology of this most
  complicated of sdB pulsators.

Title: Modelling C/O/Ne dominated accretion discs in ultra-compact
    X-ray binaries
Authors: Hammer, N. J.; Kusterer, D. -J.; Nagel, T.; Rauch, T.;
   Werner, K.; Dreizler, S.
Bibcode: 2005ASPC..330..333H
Altcode:
  We present synthetic UV/optical NLTE spectra for the accretion disc
  in the ultra-compact LMXB 4U 1626-67. By assuming a radial α-disc
  structure, we perform full non-LTE radiative transfer calculations
  to compute the detailed vertical structure of the disc. Comparing our
  results with HST spectra confirms that the disc is H and He depleted,
  but mainly composed of C and O.

Title: Detection of planetary transits using wavelet analysis and
    genetic algorithms.
Authors: Husser, T. -O.; Dreizler, S.; Solanki, S.; Thomas, R.
Bibcode: 2005AN....326R.628H
Altcode:
  No abstract at ADS

Title: Automated Difference Imaging for extrasolar planet searches.
Authors: Israel, H.; Hessman, F. V.; Dreizler, S.; Schuh, S.
Bibcode: 2005AN....326..629I
Altcode:
  No abstract at ADS

Title: NLTE Spectral Analysis of Accretion Discs in Ultracompact
    X-ray Binaries
Authors: Nagel, T.; Hammer, N. J.; Rauch, T.; Werner, K.; Dreizler, S.
Bibcode: 2005ASPC..330...73N
Altcode:
  We present first results of a NLTE spectral analysis of the accretion
  discs in the ultracompact X-ray binaries 4U 0614+091 and 4U 1626-67,
  performed with our accretion disc code AcDc. We show, that it is
  possible to give an upper limit for the abundances of hydrogen. The
  emission line features seen in the spectrum of 4U 1626-67 can be
  modeled qualitatively with irradiation of the accretion disc by the
  central neutron star.

Title: The Spectral Variability of Pulsating Stars: PG 1159-035
Authors: Stahn, T.; Dreizler, S.; Werner, K.
Bibcode: 2005ASPC..334..545S
Altcode: 2005astro.ph..2013S
  With 10m class telescopes as well as with time-tagging detectors
  on board of HST and FUSE, the analysis of time-resolved spectra
  for pulsating white dwarfs becomes feasible. We present simulated
  time-resolved spectra for the hot pulsating white dwarf PG 1159-035
  and compare these models with observational data of the 516 s mode
  based on HST-STIS spectroscopy. A determination of the pulsation mode
  by the spectral variability of PG 1159-035 seems to be impossible for
  the moment.

Title: Spectral Analyses of DO White Dwarfs and PG1159 Stars from
    the Sloan Digital Sky Survey
Authors: Huegelmeyer, S. D.; Dreizler, S.; Werner, K.; Nitta, A.;
   Kleinman, S. J.; Krzesiński, J.
Bibcode: 2005ASPC..334..233H
Altcode: 2005astro.ph..1252H
  SDSS (DR1 and DR2) has recently proposed 7 new DO white dwarfs as
  well as 6 new PG1159 stars. This is a significant increase in the
  known number of DOs and PG1159 stars. Our spectral analyses provide
  stellar parameters which can then be used to derive constraints for the
  evolution of H-deficient white dwarfs. A comprehensive understanding
  of these objects is still severely hampered by low-number statistics.

Title: Investigation of the Spectral Variability of PG 1159-035
Authors: Dreizler, S.; Werner, K.; Stahn, T.
Bibcode: 2005ASPC..334..512D
Altcode:
  Based on HST-STIS spectra of PG 1159-035, a hot, variable white dwarf,
  we investigate the response of the stellar atmosphere to pulsations. The
  observations are compared to theoretical model atmospheres which
  allows to derive an amplitude for the variation of the effective
  temperature of about 1 250 K. Additionally, we derive amplitudes for
  radial velocity variations with 4.5 km s<SUP>-1</SUP> for the second
  strongest optical mode.

Title: NLTE Analysis of the Ultra-short Period White-Dwarf Binary
    RX J0806.3+1527
Authors: Steiper, J.; Reinsch, K.; Dreizler, S.
Bibcode: 2005ASPC..334..399S
Altcode: 2005astro.ph..1255S
  RX J0806.3+1527 is suspected to be a double-degenerate white dwarf
  binary. We present first results of our NLTE analysis of its optical
  spectrum. The VLT/FORS1 data show a composite spectrum consisting of a
  blue continuum and superimposed emission lines of the He II Pickering
  series and, possibly, the H Balmer series. Our models are based on
  hot white dwarf atmospheres and include illumination effects onto
  the secondary star. The physical parameters and chemical abundances
  derived from the comparison of the observed spectrum with a grid
  of model atmospheres provide constraints on the true nature of this
  enigmatic binary and on the models proposed so far.

Title: HST and FUSE Spectroscopy of Hot Hydrogen-Rich Central Stars
    of Planetary Nebulae
Authors: Traulsen, I.; Hoffmann, A. I. D.; Rauch, T.; Werner, K.;
   Dreizler, S.; Kruk, J. W.
Bibcode: 2005ASPC..334..325T
Altcode: 2004astro.ph.11403T
  High-resolution UV spectra, obtained with HST and FUSE, enable us
  to analyse hot hydrogen-rich central stars in detail. Up to now,
  optical hydrogen and helium lines have been used to derive temperature
  and surface gravity. Those lines, however, are rather insensitive; in
  particular, neutral helium lines have completely vanished in the hottest
  central stars. Therefore, we have concentrated on ionization balances
  of metals, which have a rich line spectrum in the UV, to establish a
  new temperature scale for our sample. Furthermore, we have determined
  abundances of light metals, which had been poorly known before. They
  show considerable variation from star to star. We present results of
  quantitative spectral analyses performed with non-LTE model atmospheres.

Title: Subluminous O Stars from the ESO Supernova Progenitor Survey -
    Observation versus Theory
Authors: Ströer, A.; Heber, U.; Lisker, T.; Napiwotzki, R.;
   Dreizler, S.
Bibcode: 2005ASPC..334..309S
Altcode: 2004astro.ph.10433S
  The ESO Supernova Progenitor Survey (SPY) has identified 58 (mostly
  helium-rich) subluminous O stars. We use the Balmer line strength to
  distinguish sdO from He-sdO (no Balmer lines) and present the results
  of the analyses of high resolution optical VLT-UVES spectra using an
  extensive grid of NLTE atmosphere models covering a large range in
  T<SUB>eff</SUB>, log{g} and helium abundances. The stellar atmospheric
  parameters are derived from line profile fits using a χ<SUP>2</SUP>
  technique. The resulting distribution in the (T<SUB>eff</SUB>, log{g})
  diagram as well as the luminosity function are discussed in the context
  of stellar evolution scenarios. By combining our results with those for
  the sdB stars from SPY (Lisker et al. 2004) we discuss the implications
  for binary population synthesis models of Han et al. (2003). Models with
  a low CEE efficiency and a constant mass ratio distribution provide a
  reasonable explanation of the observed properties of the SPY sample
  of sdB and sdO stars indicating that the sdO stars form the hot and
  luminous extension of the sdB sequence. However, for the He-sdO stars
  none of the considered evolution scenarios are in agreement with the
  measured parameters of our programme stars. We conclude that He-sdO
  stars are formed by a different process than the sdB and sdO stars.

Title: Successors of White Dwarfs -- Blue Hook Stars and the Late
    Hot Flasher Scenario
Authors: Moehler, S.; Sweigart, A. V.; Landsman, W. B.; Hammer, N. J.;
   Dreizler, S.
Bibcode: 2005ASPC..334...73M
Altcode:
  Recent UV observations of massive globular clusters show a significant
  population of hot stars fainter than the zero-age horizontal branch
  (``blue hook'' stars), which cannot be explained by canonical stellar
  evolution. Stars which experience unusually large mass loss on the
  red giant branch and which subsequently undergo the helium core
  flash while descending the white dwarf cooling curve could populate
  this region. Such objects should show higher temperatures than the
  hottest canonical horizontal branch stars and should have helium- and
  carbon-rich atmospheres. As a test of this late hot flasher scenario,
  we have obtained and analysed medium resolution spectra of a sample of
  blue hook stars to derive their atmospheric parameters. While these
  parameters generally support the late hot flasher scenario there
  remain important differences between our observational results and
  theoretical predictions.

Title: Metal Abundances in Hot DA White Dwarfs
Authors: Schuh, S.; Barstow, M. A.; Dreizler, S.
Bibcode: 2005ASPC..334..237S
Altcode: 2004astro.ph.11643S
  We compare measured element abundances in hot DA white dwarfs from
  UV observations to predictions from our self-consistent non-LTE model
  atmosphere diffusion calculations.

Title: Iron Abundance in Hydrogen-Rich Central Stars of Planetary
    Nebulae
Authors: Hoffmann, A. I. D.; Traulsen, I.; Rauch, T.; Werner, K.;
   Dreizler, S.; Kruk, J. W.
Bibcode: 2005ASPC..334..321H
Altcode: 2004astro.ph.11404H
  We report on an on-going analysis of high-resolution UV spectra
  of hot hydrogen-rich central stars of planetary nebulae (CSPN),
  obtained with the Hubble Space Telescope and FUSE. Since UV spectra
  of many CSPN are dominated by Fe and Ni lines, we intend to use them
  as temperature indicators to check the CSPN temperature scale we have
  derived earlier from CNO ionization balances. Furthermore, the observed
  line strengths of heavy metals show large variations between different
  objects suggesting a possible spread in abundances. We will determine
  abundances of iron group elements by quantitative spectral analyses
  with non-LTE model atmospheres.

Title: On Possible Oxygen/Neon White Dwarfs: H1504+65 and the White
    Dwarf Donors in Ultracompact X-ray Binaries
Authors: Werner, K.; Hammer, N. J.; Nagel, T.; Rauch, T.; Dreizler, S.
Bibcode: 2005ASPC..334..165W
Altcode: 2004astro.ph.10690W
  We discuss the possibility to detect O/Ne white dwarfs by evidence
  for Ne overabundances. The hottest known WD, H1504+65, could be the
  only single WD for which we might be able to prove its O/Ne nature
  directly. Apart from this, strong Ne abundances are known or suspected
  only from binary systems, namely from a few novae, and from a handful
  of LMXBs. We try to verify the hypothesis that the latter might host
  strongly ablated O/Ne WD donors, by abundance analyses of the accretion
  disks in these systems. In any case, to conclude on O/Ne WDs just by
  strong Ne overabundances is problematic, because Ne enrichment also
  occurs by settling of this species into the core of C/O WDs.

Title: Discovery of a Long-Period Photometric Variation in the V361
    Hya Star HS 0702+6043
Authors: Schuh, S.; Huber, J.; Green, E. M.; O'Toole, S. J.; Dreizler,
   S.; Heber, U.; Fontaine, G.
Bibcode: 2005ASPC..334..530S
Altcode: 2004astro.ph.11640S
  We report the discovery of a long-period g-mode oscillation in the
  previously known short-period p-mode sdB pulsator HS 0702+6043. This
  makes this star an extraordinary object, unique as a member of the
  family of sdB pulsators, and one of the very few known pulsating
  stars overall exhibiting excited modes along both the acoustic and
  gravity branches of the nonradial pulsation spectrum. Because p-modes
  and g-modes probe different regions of a pulsating star, HS 0702+6043
  holds a tremendous potential for future detailed asteroseismological
  investigations.

Title: Rotation Velocities of DA White Dwarfs with Convective
    Atmospheres}
Authors: Karl, C.; Heber, U.; Napiwotzki, R.; Dreizler, S.; Koester,
   D.; Reid, I. N.
Bibcode: 2005ASPC..334..241K
Altcode:
  The sharp H{α} NLTE line cores of hydrogen rich (DA) white dwarfs
  allow their projected rotational velocities to be determined. High
  resolution optical spectra of 22 stars obtained with the Keck I
  telescope are matched by synthetic spectra computed from a grid of NLTE
  model atmospheres. We concentrate preferentially on hydrogen-rich white
  dwarfs with convective atmospheres, i.e. with T<SUB>eff</SUB> &lt; 14
  000 K. Previous analyses found DA white dwarfs hotter than 14 000 K to
  be very slow rotators and rarely show any spectroscopically detectable
  rotation. For 19 of our program stars we were able to derive projected
  rotational velocities or upper limits. Combining our results with
  those from two similar studies (Heber et al 1997, paper I and Koester
  et al. 1998, paper II), we have obtained information of 56 DA white
  dwarfs. The fraction of rotating DA white dwarfs whose line profiles can
  be matched for a vanishing projected rotation velocities is high for
  hot white dwarfs with radiative atmospheres (25 out of 28) with upper
  limits ranging from 1 kms<SUP>-1</SUP> to 24 kms<SUP>-1</SUP>, whereas
  amongst the cool white dwarfs with presumably convective atmospheres
  only for a few stars (8 out of 22) no additional line broadening has
  to be invoked to explain their observed Hα line profiles resulting
  in upper limits to v sin i of 7 kms<SUP>-1</SUP> to 35 kms<SUP>-1</SUP>.

Title: Rotation velocities of white dwarfs. III. DA stars with
    convective atmospheres
Authors: Karl, C. A.; Napiwotzki, R.; Heber, U.; Dreizler, S.; Koester,
   D.; Reid, I. N.
Bibcode: 2005A&A...434..637K
Altcode:
  The sharp Hα NLTE line cores of hydrogen-rich (DA) white dwarfs
  allow their projected rotational velocities to be determined. High
  resolution optical spectra of 22 stars obtained with the Keck I
  telescope are matched by synthetic spectra computed from a grid of
  NLTE model atmospheres. In this paper, the third in a series on white
  dwarf rotation, we concentrate preferentially on DA white dwarfs
  with convective atmospheres, i.e. with T<SUB>eff</SUB> &lt; 14 000
  K. Previous analyses found DA white dwarfs hotter than 14 000 K to be
  very slow rotators and rarely show any spectroscopically detectable
  rotation. For 19 of our programme stars we were able to derive projected
  rotational velocities or upper limits. No rotation could be detected for
  seven stars in our sample. However twelve stars show significant line
  broadening. In the case of the ZZ Ceti star G 117-B15A, the observed
  Hα line profile cannot be matched by a rotationally broadened profile
  as its line core is too narrow. Combining our results with those from
  two similar studies, we have obtained information on the rotation or
  other line broadening mechanisms (such as caused by magnetic fields)
  of 56 DA white dwarfs. The fraction of rotating DA white dwarfs
  whose line profiles can be matched for a vanishing projected rotation
  velocity is high for hot white dwarfs with radiative atmospheres (25
  out of 28). Amongst the cool white dwarfs with presumedly convective
  atmospheres, only for a few stars (8 out of 22) has no additional line
  broadening to be invoked to explain their observed Hα line profiles. We
  conjecture that the physics of Hα line formation in convective DA
  white dwarf atmospheres is not yet sufficiently well understood and
  additional observational and theoretical efforts have to be made.

Title: The D/H Ratio toward PG 0038+199
Authors: Williger, Gerard M.; Oliveira, Cristina; Hébrard, Guillaume;
   Dupuis, Jean; Dreizler, Stefan; Moos, H. Warren
Bibcode: 2005ApJ...625..210W
Altcode: 2005astro.ph..1320W
  We determine the D/H ratio in the interstellar medium toward the
  DO white dwarf PG 0038+199 using spectra from the Far Ultraviolet
  Spectroscopic Explorer (FUSE), with ground-based support from
  Keck HIRES. We employ curve-of-growth, apparent optical depth,
  and profile-fitting techniques to measure the column densities
  and limits of many other species (H<SUB>2</SUB>, Na I, C I, C II,
  C III, N I, N II, O I, Si II, P II, S III, Ar I, and Fe II),
  which allows us to determine related ratios such as D/O, D/N,
  and the H<SUB>2</SUB> fraction. Our efforts are concentrated on
  measuring gas-phase D/H, which is key to understanding Galactic
  chemical evolution, and comparing it to predictions from big bang
  nucleosynthesis. We find column densities logN(HI)=20.41+/-0.08,
  logN(DI)=15.75+/-0.08, and logN(H<SUB>2</SUB>)=19.33+/-0.04,
  yielding a molecular hydrogen fraction of 0.14+/-0.02 (2 σ errors),
  with an excitation temperature of 143+/-5 K. The high H I column
  density implies that PG 0038+199 lies outside of the Local Bubble;
  we estimate its distance to be 297<SUP>+164</SUP><SUB>-104</SUB>
  pc (1 σ). [DI+HD]/[HI+2H<SUB>2</SUB>] toward PG 0038+199 is
  1.91<SUP>+0.52</SUP><SUB>-0.42</SUB>×10<SUP>-5</SUP> (2 σ). There
  is no evidence of component structure on the scale of Δv&gt;8 km
  s<SUP>-1</SUP>, based on Na I, but there is marginal evidence for
  structure on smaller scales. The D/H value is high compared to the
  majority of recent D/H measurements but consistent with the values
  for two other measurements at similar distances. D/O is in agreement
  with other distant measurements. The scatter in D/H values beyond
  ~100 pc remains a challenge for Galactic chemical evolution. <P />This
  paper is dedicated in memory of Ervin J. Williger, father of the first
  author, who passed away on 2003 September 13. His enthusiastic support
  and encouragement were essential to its successful completion. <P
  />Based on data from the Far Ultraviolet Spectroscopic Explorer and
  the W. M. Keck Observatory.

Title: Whole Earth Telescope observations of BPM 37093: A
    seismological test of crystallization theory in white dwarfs
Authors: Kanaan, A.; Nitta, A.; Winget, D. E.; Kepler, S. O.;
   Montgomery, M. H.; Metcalfe, T. S.; Oliveira, H.; Fraga, L.; da
   Costa, A. F. M.; Costa, J. E. S.; Castanheira, B. G.; Giovannini, O.;
   Nather, R. E.; Mukadam, A.; Kawaler, S. D.; O'Brien, M. S.; Reed,
   M. D.; Kleinman, S. J.; Provencal, J. L.; Watson, T. K.; Kilkenny,
   D.; Sullivan, D. J.; Sullivan, T.; Shobbrook, B.; Jiang, X. J.;
   Ashoka, B. N.; Seetha, S.; Leibowitz, E.; Ibbetson, P.; Mendelson,
   H.; Meištas, E. G.; Kalytis, R.; Ališauskas, D.; O'Donoghue, D.;
   Buckley, D.; Martinez, P.; van Wyk, F.; Stobie, R.; Marang, F.; van
   Zyl, L.; Ogloza, W.; Krzesinski, J.; Zola, S.; Moskalik, P.; Breger,
   M.; Stankov, A.; Silvotti, R.; Piccioni, A.; Vauclair, G.; Dolez, N.;
   Chevreton, M.; Deetjen, J.; Dreizler, S.; Schuh, S.; Gonzalez Perez,
   J. M.; Østensen, R.; Ulla, A.; Manteiga, M.; Suarez, O.; Burleigh,
   M. R.; Barstow, M. A.
Bibcode: 2005A&A...432..219K
Altcode: 2004astro.ph.11199K
  BPM 37093 is the only hydrogen-atmosphere white dwarf currently known
  which has sufficient mass (~1.1 M<SUB>⊙</SUB>) to theoretically
  crystallize while still inside the ZZ Ceti instability strip
  (T<SUB>eff</SUB>∼12 000 K). As a consequence, this star represents
  our first opportunity to test crystallization theory directly. If the
  core is substantially crystallized, then the inner boundary for each
  pulsation mode will be located at the top of the solid core rather
  than at the center of the star, affecting mainly the average period
  spacing. This is distinct from the “mode trapping” caused by
  the stratified surface layers, which modifies the pulsation periods
  more selectively. In this paper we report on Whole Earth Telescope
  observations of BPM 37093 obtained in 1998 and 1999. Based on a simple
  analysis of the average period spacing we conclude that a large fraction
  of the total stellar mass is likely to be crystallized. <P />Based
  on observations obtained at: Observatório do Pico dos Dias (OPD)
  Brazil, the European Southern Observatory (ESO) Chile, South African
  Astronomical Observatory (SAAO), Mt. John University Observatory
  (MJUO) New Zealand, Siding Spring Observatory (SSO) Australia, and
  Cerro Tololo Inter-American Observatory (CTIO), a division of the
  National Optical Astronomy Observatories, which is operated by the
  Association of Universities for Research in Astronomy, Inc. under
  cooperative agreement with the National Science Foundation.

Title: Stellar atmosphere modeling in the era of 10m class telescopes
Authors: Dreizler, S.
Bibcode: 2005AIPC..752...13D
Altcode:
  In this paper, I briefly summarize the basic ingredients for modeling
  stellar atmospheres. The progress in the numerical solution techniques
  has evolved in parallel to the rapid development of observing
  facilities. The modeling of stellar atmospheres in particular and
  stellar astrophysics in general are therefore important ingredients
  for our understanding of stellar, galactic and cosmic evolution.

Title: Giant Transiting Planets Observations - GITPO
Authors: Afonso, C.; Henning, Th.; Weldrake, D.; Mazeh, T.; Dreizler,
   S.
Bibcode: 2005prpl.conf.8047A
Altcode: 2005LPICo1286.8047A
  No abstract at ADS

Title: AcDc - A new code for the NLTE spectral analysis of accretion
discs: application to the helium CV AM CVn
Authors: Nagel, T.; Dreizler, S.; Rauch, T.; Werner, K.
Bibcode: 2004A&A...428..109N
Altcode: 2004astro.ph..8352N
  We present a recently developed code for detailed NLTE calculations
  of accretion disc spectra of cataclysmic variables and compact X-ray
  binaries. Assuming a radial structure of a standard α-disc, the disc
  is divided into concentric rings. For each disc ring the solution
  of the radiation transfer equation and the structure equations,
  comprising the hydrostatic and radiative equilibrium, the population
  of the atomic levels as well as charge and particle conservation,
  is done self-consistently. Metal-line blanketing and irradiation by
  the central object are taken into account. As a first application, we
  show the influence of different disc parameters on the disc spectrum
  for the helium cataclysmic variable AM CVn.

Title: Modeling He-rich Disks in AM CVn Binaries
Authors: Nagel, T.; Rauch, T.; Dreizler, S.; Werner, K.
Bibcode: 2004RMxAC..20..228N
Altcode: 2004IAUCo.194..228N
  We have developed a new code for the calculation of synthetic spectra
  and vertical structures of accretion disks in cataclysmic variables
  and compact X-ray binaries. Here we present results for the CV system
  AM CVn.

Title: Modeling of Oxygen-Neon Dominated Accretion Disks in
Ultracompact X-ray Binaries: 4U 1626-67
Authors: Werner, K.; Nagel, T.; Dreizler, S.; Rauch, T.
Bibcode: 2004RMxAC..20..146W
Altcode: 2003astro.ph.12561W; 2004IAUCo.194..146W
  We report on first results of computing synthetic spectra from H/He-poor
  accretion disks in ultracompact LMXBs. We aim at the determination
  of the chemical composition of the very low-mass donor star, which is
  the core of a former C/O white dwarf. The abundance analysis allows to
  draw conclusions on gravitational settling in WDs which is an important
  process affecting cooling times and pulsational g-mode periods.

Title: HS 2237+8154: A new pre-CV just above the period gap
Authors: Gänsicke, B. T.; Araujo-Betancor, S.; Hagen, H. -J.;
   Harlaftis, E. T.; Kitsionas, S.; Dreizler, S.; Engels, D.
Bibcode: 2004RMxAC..20..271G
Altcode: 2004IAUCo.194..271G
  We report follow-up observations of the new pre-cataclysmic variable
  HS 2237+8154, identified from the Hamburg Quasar Survey. The orbital
  period derived from ellipsoidal modulation observed in the R-band as
  well as from the Hα radial velocity variation is [orb] = 178.10±0.08
  min. We briefly discuss the evolutionary state of this system.

Title: The Rotational Velocity of Helium-rich Pre-White Dwarfs
Authors: Rauch, T.; Köper, S.; Dreizler, S.; Werner, K.; Heber, U.;
   Reid, I. Neill
Bibcode: 2004IAUS..215..573R
Altcode:
  No abstract at ADS

Title: MSST observations of the pulsating sdB star PG 1605+072
Authors: O'Toole, S. J.; Falter, S.; Heber, U.; Jeffery, C. S.;
   Dreizler, S.; Schuh, S. L.; MSST + Wet Teams,
Bibcode: 2004Ap&SS.291..457O
Altcode: 2003astro.ph..9061O
  We present the first results from the MultiSite Spectroscopic Telescope
  (MSST) observations of the sdBV star PG 1605+072. Pulsating sdB stars
  (also known as EC 14026 stars) offer the chance to gain new insights
  into the formation and evolution of extreme Horizontal Branch stars
  using the tools of asteroseismology. PG 1605+072 is an outstanding
  object in its class, with the richest frequency spectrum, the longest
  periods, and the largest variations.

Title: Helium-rich EHB Stars in Globular Clusters
Authors: Moehler, S.; Sweigart, A. V.; Landsman, W. B.; Dreizler, S.
Bibcode: 2004Ap&SS.291..231M
Altcode: 2003astro.ph..9768M
  Recent UV observations of the most massive Galactic globular clusters
  show a significant population of hot stars below the zero-age HB
  (“blue hook” stars), which cannot be explained by canonical stellar
  evolution. Stars which suffer unusually large mass loss on the red giant
  branch and thus experience the helium-core flash while descending the
  white dwarf cooling curve could populate this region. They should
  show higher temperatures than the hottest canonical HB stars and
  their atmospheres should be helium-rich and probably C/N-rich. We
  have obtained spectra of blue hook stars in ω Cen and NGC 2808 to
  test this possibility. Our analysis shows that the blue hook stars in
  these clusters reach effective temperatures well beyond the hot end of
  the canonical EHB and have higher helium abundances than canonical EHB
  stars. These results support the hypothesis that the blue hook stars
  arise from stars which ignite helium on the white dwarf cooling curve.

Title: Discovery of Gravity-Mode Pulsators among Subdwarf B Stars:
    PG 1716+426, the Class Prototype
Authors: Reed, M. D.; Green, E. M.; Callerame, K.; Seitenzahl, I. R.;
   White, B. A.; Hyde, E. A.; Giovanni, M. K.; Østensen, R.; Bronowska,
   A.; Jeffery, E. J.; Cordes, O.; Falter, S.; Edelmann, H.; Dreizler,
   S.; Schuh, S. L.
Bibcode: 2004ApJ...607..445R
Altcode:
  A new class of pulsating subdwarf B stars has recently been announced
  by Green and coworkers. Here we present a follow-up paper describing
  our observations and the pulsation structure of the class prototype
  PG 1716+426. The oscillations are multiperiodic with periods between
  0.8 and 1.4 hr (180-340 μHz) and semiamplitudes less than 0.2%. We
  also observe that the periods and amplitudes appear variable, making
  the pulsation structure of PG 1716 complicated. The periods are an
  order of magnitude longer than those seen in EC 14026 (sdBV) stars,
  implying that they are gravity modes rather than pressure modes. As
  such, they represent a new class of variable star.

Title: Multisite spectroscopic and photometric observations of the
    pulsating sdB star PG 1605+072
Authors: O'Toole, S. J.; Falter, S.; Heber, U.; Jeffery, C. S.;
   Dreizler, S.; Schuh, S. L.; Msst, The; Wet Teams
Bibcode: 2004ASPC..310..230O
Altcode: 2004IAUCo.193..230O; 2004vslg.conf..230O
  We present the first results from the MultiSite Spectroscopic Telescope
  (MSST) observations ofthe sd BV star PG 1605+072. Pulsating sdB stars
  (V361 Hya stars) offer the chance to gain new insights into the
  formation and evolution of extreme Horizontal Branch stars using the
  tools of asteroseismology. PG 1605+072 is an outstanding object in
  its class, with the richest frequency spectrum, the longest periods,
  and the largest variations. The MSST campaign took place in 2002
  May/June and we present here the massive data set, madeup of 399 hr of
  photometry and 151 hr of spectroscopy. The overall aims of the project
  are to examine light/velocity amplitude ratios and phase differences,
  changes in equivalent width/line index, and λ-dependence of photometric
  amplitudes, and to use these properties for mode identification.

Title: HS 2237+8154: On the onset of mass transfer or entering the
    period gap?
Authors: Gänsicke, B. T.; Araujo-Betancor, S.; Hagen, H. -J.;
   Harlaftis, E. T.; Kitsionas, S.; Dreizler, S.; Engels, D.
Bibcode: 2004A&A...418..265G
Altcode: 2004astro.ph..2189G
  We report follow-up observations of a new white dwarf/red dwarf binary
  HS 2237+8154, identified as a blue variable star from the Hamburg
  Quasar Survey. Ellipsoidal modulation observed in the R band as well
  as the Hα radial velocity variations measured from time-resolved
  spectroscopy determine the orbital period to be P<SUB>orb</SUB>=178.10
  ± 0.08 min. The optical spectrum of HS 2237+8154 is well described
  by a combination of a T<SUB>eff</SUB>=11 500 ± 1500 K white dwarf
  (assuming log g=8) and a dM 3.5 ± 0.5 secondary star. The distance
  implied from the flux scaling factors of both stellar components is
  d=105 ± 25 pc. Combining the constraints obtained from the radial
  velocity of the secondary and from the ellipsoidal modulation, we
  derive a binary inclination of i≃50<SUP>°</SUP>-70<SUP>°</SUP>
  and stellar masses of M<SUB>wd</SUB>=0.47-0.67 M<SUB>⊙</SUB> and
  M<SUB>sec</SUB>=0.2-0.4 M<SUB>⊙</SUB>. All observations imply that
  the secondary star must be nearly Roche-lobe filling. Consequently, HS
  2237+8154 may be either a pre-cataclysmic variable close to the start
  of mass transfer, or - considering its orbital period - a cataclysmic
  variable that terminated mass transfer and entered the period gap, or
  a hibernating nova. <P />Based in part on observations made at the 1.2
  m telescope, located at Kryoneri Korinthias, and owned by the National
  Observatory of Athens, Greece, and with the Isaac Newton Telescope,
  which is operated on the island of La Palma by the Isaac Newton Group
  in the Spanish Observatorio del Roque de los Muchachos of the Instituto
  de Astrofisica de Canarias.

Title: Observations of the pulsating subdwarf B star Feige 48:
    Constraints on evolution and companions
Authors: Reed, M. D.; Kawaler, S. D.; Zola, S.; Jiang, X. J.; Dreizler,
   S.; Schuh, S. L.; Deetjen, J. L.; Kalytis, R.; Meištas, E.; Janulis,
   R.; Ališauskas, D.; Krzesiński, J.; Vuckovic, M.; Moskalik, P.;
   Ogłoza, W.; Baran, A.; Stachowski, G.; Kurtz, D. W.; González Pérez,
   J. M.; Mukadam, A.; Watson, T. K.; Koen, C.; Bradley, P. A.; Cunha,
   M. S.; Kilic, M.; Klumpe, E. W.; Carlton, R. F.; Handler, G.; Kilkenny,
   D.; Riddle, R.; Dolez, N.; Vauclair, G.; Chevreton, M.; Wood, M. A.;
   Grauer, A.; Bromage, G.; Solheim, J. E.; Østensen, R.; Ulla, A.;
   Burleigh, M.; Good, S.; Hürkal, Ö.; Anderson, R.; Pakstiene, E.
Bibcode: 2004MNRAS.348.1164R
Altcode: 2003astro.ph.11476R
  Since pulsating subdwarf B (sdBV or EC14026) stars were first
  discovered, observational efforts have tried to realize their potential
  for constraining the interior physics of extreme horizontal branch
  stars. Difficulties encountered along the way include uncertain mode
  identifications and a lack of stable pulsation mode properties. Here we
  report on Feige 48, an sdBV star for which follow-up observations have
  been obtained spanning more than four years. These observations show
  some stable pulsation modes. <P />We resolve the temporal spectrum into
  five stable pulsation periods in the range 340-380 s with amplitudes
  less than 1 per cent, and two additional periods that appear in one
  data set each. The three largest amplitude periodicities are nearly
  equally spaced, and we explore the consequences of identifying them as
  a rotationally split l= 1 triplet by consulting a representative stellar
  model. <P />The general stability of the pulsation amplitudes and phases
  allows us to use the pulsation phases to constrain the time-scale
  of evolution for this sdBV star. Additionally, we are able to place
  interesting limits on any stellar or planetary companion to Feige 48.

Title: Spectroscopic analyses of the blue hook stars in NGC 2808:
    A more stringent test of the late hot flasher scenario
Authors: Moehler, S.; Sweigart, A. V.; Landsman, W. B.; Hammer, N. J.;
   Dreizler, S.
Bibcode: 2004A&A...415..313M
Altcode: 2003astro.ph.11215M
  Recent UV observations of the globular cluster NGC 2808 (Brown et
  al. \cite{brsw01}) show a significant population of hot stars fainter
  than the zero-age horizontal branch (``blue hook'' stars), which
  cannot be explained by canonical stellar evolution. Their results
  suggest that stars which experience unusually large mass loss on
  the red giant branch and which subsequently undergo the helium core
  flash while descending the white dwarf cooling curve could populate
  this region. Theory predicts that these ``late hot flashers'' should
  show higher temperatures than the hottest canonical horizontal branch
  stars and should have helium- and carbon-rich atmospheres. As a test
  of this late hot flasher scenario, we have obtained and analysed
  medium resolution spectra of a sample of blue hook stars in NGC 2808
  to derive their atmospheric parameters. Using the same procedures,
  we have also re-analyzed our earlier spectra of the blue hook stars in
  ω Cen (Moehler et al. \cite{mosw02}) for comparison with the present
  results for NGC 2808. The blue hook stars in these two clusters are both
  hotter (T<SUB>eff</SUB> ≥35 000 K) and more helium-rich than canonical
  extreme horizontal branch stars in agreement with the late hot flasher
  scenario. Moreover, we find indications for carbon enhancement in the
  three most helium-enriched stars in NGC 2808. However, the blue hook
  stars still show some hydrogen in their atmospheres, perhaps indicating
  that some residual hydrogen survives a late hot flash and then later
  diffuses to the surface during the horizontal branch phase. We note
  that the presence of blue hook stars apparently depends mostly on the
  total mass of the globular cluster and not so much on its horizontal
  branch morphology. <P />Based on observations collected at the European
  Southern Observatory, Chile (ESO proposal 68.D-0248).

Title: 2MASS J0516288+260738: a new low-mass eclipsing binary system.
Authors: Schuh, S.; Drechsel, H.; Hauschildt, P.; Handler, G.; Endl,
   M.; Dreizler, S.
Bibcode: 2004ANS...325R..84S
Altcode: 2004ANS...325a..84S; 2004ANS...325..P09S
  No abstract at ADS

Title: Asteroseismology of the β Cephei star ν Eridani -
    II. Spectroscopic observations and pulsational frequency analysis
Authors: Aerts, C.; De Cat, P.; Handler, G.; Heiter, U.; Balona, L. A.;
   Krzesinski, J.; Mathias, P.; Lehmann, H.; Ilyin, I.; De Ridder, J.;
   Dreizler, S.; Bruch, A.; Traulsen, I.; Hoffmann, A.; James, D.;
   Romero-Colmenero, E.; Maas, T.; Groenewegen, M. A. T.; Telting,
   J. H.; Uytterhoeven, K.; Koen, C.; Cottrell, P. L.; Bentley, J.;
   Wright, D. J.; Cuypers, J.
Bibcode: 2004MNRAS.347..463A
Altcode:
  We undertook a multisite spectroscopic campaign for the β Cephei star
  ν Eridani. A total of 2294 high-resolution spectra were obtained
  from telescopes at 11 different observatories around the world. The
  time base of dedicated multisite observations is 88 d. To this
  data set we have added 148 older, previously unpublished spectra,
  such that the overall time-span of the 2442 spectra is 430 d. The
  analysis of the radial velocity variations derived from the SiIII
  triplet centred on 4560Å leads to 19 significant frequencies, of
  which seven correspond to independent pulsation frequencies. Five of
  these are members of multiplets with an average spacing of 0.018 +/-
  0.002 cd<SUP>-1</SUP>. Our spectroscopic results agree well with
  those derived from a simultaneous multisite photometric campaign of
  the star, albeit that we do not recover their low frequency at 0.43218
  cd<SUP>-1</SUP>. We find three different candidate frequencies below
  1 cd<SUP>-1</SUP> instead. We also find that the radial velocity
  amplitude of the main mode has increased by some 30 per cent over
  the last 15 years, which is consistent with the photometry data. We
  derive a relative equivalent width variation of 6.5 per cent, which
  is completely dominated by the main radial mode. The phase difference
  between the radial velocity and light variations for the main frequency
  is , which is clearly deviant from the adiabatic value and confirms the
  radial nature of the dominant mode. The spectral line broadening leads
  to an upper limit of 20 km s<SUP>-1</SUP> for vsini, which is consistent
  with the long rotation period derived from the frequency splittings.

Title: Time resolved spectroscopy of the sdB variable PG1605+072
Authors: Dreizler, Stefan
Bibcode: 2004fuse.prop.C020D
Altcode:
  The recent discovery of radial and nonradial mode pulsations in more
  than 20 sdB stars make them primary targets for asteroseismology
  to probe their internal structure and discern their evolutionary
  status; the latter is crucial for reasons as diverse as understanding
  the late stages of stellar evolution and the calibration of the
  observed ultraviolet upturn in giant elliptical galaxies as an age
  indicator. Central to any asteroseismological study is an identification
  of the pulsation modes. Photometric studies have failed to identify
  modes from optical light curves. Line profile and flux variations in
  the far ultraviolet offer a promising way to disentangle the pulsation
  modes by comparison with detailed model predictions. PG1605+072 is
  an outstanding target among the sdB variables because it displays
  the richest period spectrum (&gt;50 pulsation periods), largest
  amplitudes and longest periods, which makes it the primary target for
  a spectroscopic FUV study.

Title: <ASTROBJ>2MASS J0516288+260738</ASTROBJ>: Discovery of the
    first  eclipsing late K + Brown dwarf binary system?
Authors: Schuh, S. L.; Handler, G.; Drechsel, H.; Hauschildt, P.;
   Dreizler, S.; Medupe, R.; Karl, C.; Napiwotzki, R.; Kim, S. -L.; Park,
   B. -G.; Wood, M. A.; Paparó, M.; Szeidl, B.; Virághalmy, G.; Zsuffa,
   D.; Hashimoto, O.; Kinugasa, K.; Taguchi, H.; Kambe, E.; Leibowitz,
   E.; Ibbetson, P.; Lipkin, Y.; Nagel, T.; Göhler, E.; Pretorius, M. L.
Bibcode: 2003A&A...410..649S
Altcode: 2003astro.ph..8329S
  We report the discovery of a new eclipsing system less than
  one arcminute south of the pulsating DB white dwarf <ASTROBJ>KUV
  05134+2605</ASTROBJ>. The object could be identified with the point
  source <ASTROBJ>2MASS J0516288+260738</ASTROBJ> published by the Two
  Micron All Sky Survey. We present and discuss the first light curves
  as well as some additional colour and spectral information. The
  eclipse period of the system is 1.29 d, and, assuming this to be
  identical to the orbital period, the best light curve solution yields
  a mass ratio of m<SUB>2</SUB>/m<SUB>1</SUB>=0.11, a radius ratio of
  r<SUB>2</SUB>/r<SUB>1</SUB>~ 1 and an inclination of 74<SUP>o</SUP>. The
  spectral anaylsis results in a T<SUB>eff</SUB>=4200 K for the
  primary. On this basis, we suggest that the new system probably consists
  of a late K + Brown dwarf (which would imply a system considerably
  younger than ~0.01 Gyr to have r<SUB>2</SUB>/r<SUB>1</SUB>~ 1), and
  outline possible future observations. <P />This paper uses observations
  made at the Bohyunsan Optical Astronomy Observatory of Korea Astronomy
  Observatory, at the South African Astronomical Observatory (SAAO), at
  the 0.9 m telescope at Kitt Peak National Observatory recommissioned
  by the Southeastern Association for Research in Astronomy (SARA),
  at Gunma Astronomical Observatory established by Gunma prefecture,
  Japan, at the Florence and George Wise Observatory, operated by the
  Tel-Aviv University, Israel and at Piszkésteto, the mountain station
  of Konkoly Observatory of the Hungarian Academy of Science, Hungary. <P
  />This publication makes use of data products from the Two Micron All
  Sky Survey, a joint project of the University of Massachusetts and
  the Infrared Processing and Analysis Center / California Institute of
  Technology, funded by the National Aeronautics and Space Administration
  and the National Science Foundation. <P />The Digitized Sky Survey was
  produced at the Space Telescope Science Institute under US Government
  grant NAG W-2166. The images of these surveys are based on photographic
  data obtained using the Oschin Schmidt Telescope on Palomar Mountain
  and the UK Schmidt Telescope. The plates were processed into the present
  compressed digital form with the permission of these institutions.

Title: A Whole Earth Telescope campaign on the pulsating subdwarf
    B binary system PG 1336-018 (NY Vir)
Authors: Kilkenny, D.; Reed, M. D.; O'Donoghue, D.; Kawaler, S. D.;
   Mukadam, A.; Kleinman, S. J.; Nitta, A.; Metcalfe, T. S.; Provencal,
   J. L.; Watson, T. K.; Sullivan, D. J.; Sullivan, T.; Shobbrook, R.;
   Jiang, X. J.; Joshi, S.; Ashoka, B. N.; Seetha, S.; Leibowitz, E.;
   Ibbetson, P.; Mendelson, H.; Meištas, E.; Kalytis, R.; Ališauskas,
   D.; Martinez, P.; van Wyk, F.; Stobie, R. S.; Marang, F.; Zola, S.;
   Krzesinski, J.; Ogłoza, W.; Moskalik, P.; Silvotti, R.; Piccioni,
   A.; Vauclair, G.; Dolez, N.; Chevreton, M.; Dreizler, S.; Schuh,
   S. L.; Deetjen, J. L.; Solheim, J. -E.; Gonzalez Perez, J. M.; Ulla,
   A.; Østensen, R.; Manteiga, M.; Suarez, O.; Burleigh, M.; Kepler,
   S. O.; Kanaan, A.; Giovannini, O.
Bibcode: 2003MNRAS.345..834K
Altcode:
  We present results from a multisite (`Whole Earth Telescope')
  photometric campaign on PG 1336-018, the close eclipsing binary system
  containing a pulsating subdwarf B (sdB) star. The main part of the
  campaign (1999 April) resulted in ~172 h of observations, representing a
  coverage of about 47 per cent, and additional data were obtained outside
  the core campaign. Periodogram analysis shows that the light variations
  are dominated by three frequencies near 5757, 5585 and 5369 μHz (~174,
  179 and 186 s, respectively), although many frequencies are present,
  particularly in the range 5000-6000 μHz (~200-170 s). We identify,
  with some confidence, 28 frequencies down to a semi-amplitude of
  0.0005 in fractional intensity (equivalent to about 0.5 mmag). It
  is clear that the pulsation frequencies of PG 1336-018 have changed
  substantially since the 1996 discovery observations were made, and that
  amplitude changes occur, at least in the dominant three frequencies, on
  relatively short time-scales (of the order of a day). On the assumption
  that the pulsating star is phase-locked in the binary system, we have
  searched for rotational splitting of frequencies near the orbital and
  half of the orbital period, but the results are confused by aliasing
  at those frequencies (due to the data gaps caused by the eclipses). A
  preliminary model qualitatively matches the distribution of frequencies
  in PG 1336-018, with some good individual correspondences, but cannot
  be considered adequate because geometric cancellation should hide some
  of the modes which are apparently detected. Analysis of the pulsations
  during eclipse recovers three of the strongest modes, but the limited
  eclipse data - which can, at best, be only about 9 per cent of the total
  - do not allow mode identification at this stage. Simulations indicate
  that an overall coverage of about 80 per cent would be required for
  this to be viable. An attempt was made to determine phase shifts in
  the pulsation frequencies as a way of directly measuring the size of
  the binary orbit, but the uncertainties in the method are comparable
  to the light travel time across the orbit (probably less than a second).

Title: Synthetic Spectra of Accretion Disks
Authors: Nagel, T.; Dreizler, S.; Werner, K.
Bibcode: 2003ANS...324...64N
Altcode: 2003ANS...324..P31N; 2003ANS...324b..64N
  No abstract at ADS

Title: Analysis of the FUSE spectrum of the sdOB EC11481-2303
Authors: Hammer, N.; Deetjen, J. L.; Dreizler, S.; Werner, K.; Kruk,
   J. W.
Bibcode: 2003ANS...324...72H
Altcode: 2003ANS...324b..72H; 2003ANS...324..P51H
  No abstract at ADS

Title: Spectral Types of Planetary Host Star Candidates: New
    Transiting Planets?
Authors: Dreizler, S.; Rauch, T.; Hauschildt, P.; Schuh, S. L.; Kley,
   W.; Werner, K.
Bibcode: 2003ANS...324....2D
Altcode: 2003ANS...324..A03D; 2003ANS...324b...2D
  No abstract at ADS

Title: HST UV-spectroscopy of Hot Central Stars of Planetary Nebulae
Authors: Traulsen, I.; Hoffmann, A.; Dreizler, S.; Rauch, T.;
   Werner, K.
Bibcode: 2003ANS...324..144T
Altcode: 2003ANS...324c.144T; 2003ANS...324..P60T
  No abstract at ADS

Title: Population Membership of White Dwarfs from the SPY Project
Authors: Pauli, E. -M.; Napiwotzki, R.; Altmann, M.; Heber, U.;
   Dreizler, S.; Kerber, F.; Odenkirchen, M.; Spy Consortium
Bibcode: 2003ANS...324...36P
Altcode: 2003ANS...324b..36P; 2003ANS...324..G04P
  No abstract at ADS

Title: Improved Results for Equilibrium Abundances from Diffusion
    Calculations
Authors: Schuh, S. L.; Dreizler, S.
Bibcode: 2003ANS...324...72S
Altcode: 2003ANS...324..P50S; 2003ANS...324b..72S
  No abstract at ADS

Title: To be or Not to Be a Late Hot Flasher
Authors: Moehler, S.; Sweigart, A. V.; Landsman, W. B.; Dreizler, S.
Bibcode: 2003ANS...324...79M
Altcode: 2003ANS...324b..79M; 2003ANS...324..P66M
  No abstract at ADS

Title: OGLE-TR-3: A possible new transiting planet
Authors: Dreizler, S.; Hauschildt, P. H.; Kley, W.; Rauch, T.; Schuh,
   S. L.; Werner, K.; Wolff, B.
Bibcode: 2003A&A...402..791D
Altcode: 2003astro.ph..3183D
  Recently, 59 low-luminosity object transits were reported from
  the Optical Gravitational Lensing Experiment (OGLE). Our follow-up
  low-resolution spectroscopy of 16 candidates provided two objects,
  <ASTROBJ>OGLE-TR-3</ASTROBJ> and <ASTROBJ>OGLE-TR-10</ASTROBJ>,
  which have companions with radii compatible with those of gas-giant
  planets. Further high-resolution spectroscopy revealed a very low
  velocity variation (&lt;500 m s<SUP>-1</SUP>) of the host star
  <ASTROBJ>OGLE-TR-3</ASTROBJ> which may be caused by its unseen
  companion. An analysis of the radial velocity and light curve results
  in M&lt;2.5 M<SUB>Jup</SUB>, R&lt;1.6 R<SUB>Jup</SUB>, and an orbital
  separation of about 5 R<SUB>sun</SUB>, which makes it the planet with
  the shortest period known. This allows to identify the low-luminosity
  companion of <ASTROBJ>OGLE-TR-3</ASTROBJ> as a possible new gas-giant
  planet. If confirmed, this makes <ASTROBJ>OGLE-TR-3</ASTROBJ> together
  with <ASTROBJ>OGLE-TR-56</ASTROBJ> the first extrasolar planets
  detected via their transit light curves. <P />Based on observations
  collected at the European Southern Observatory, Paranal, Chile (ESO
  Programme 269.C-5034).

Title: Simultaneous time-series spectroscopy and multi-band photometry
    of the sdBV PG 1605+072
Authors: Falter, S.; Heber, U.; Dreizler, S.; Schuh, S. L.; Cordes,
   O.; Edelmann, H.
Bibcode: 2003A&A...401..289F
Altcode: 2003astro.ph..1604F
  We present time-series spectroscopy and multi-band photometry of the
  sdBV PG 1605+072 carried out simultaneously at the Calar Alto 2.2-m
  and 3.5-m telescopes. The periodogram analysis of the radial velocity
  curves reveals three frequencies at 2.078, 2.756, and 1.985 mHz for
  H<SUB>beta </SUB> and at 2.076, 2.753, and 1.978 mHz for H<SUB>gamma
  </SUB>. The corresponding radial velocity amplitudes are 12.7, 8.0,
  and 7.9 km s<SUP>-1</SUP> for H<SUB>beta </SUB> and 14.3, 6.5, and 7.2
  km s<SUP>-1</SUP> for H<SUB>gamma </SUB>. Furthermore, we found five
  frequencies that are present in all wavelength bands of the BUSCA
  photometer. The frequencies detected in the radial velocity curves
  are recovered by the photometric measurements. Moreover, additional
  frequencies were present in the periodograms which could not be
  identified in all four bands simultaneously. The comparison of the
  amplitudes presented here with previous results from radial velocity
  and photometric observations of PG 1605+072 shows a significant change
  or even switch in the power of the modes within short time scales,
  i.e. about one year. No changes in frequency were registered and
  the phases of the modes show no wavelength dependency within our
  multi-band photometry. <P />Based on observations obtained at the
  German-Spanish Astronomical Center (DSAZ), Calar Alto, operated by
  the Max-Planck-Institut für Astronomie Heidelberg jointly with the
  Spanish National Commission for Astronomy.

Title: The everchanging pulsating white dwarf GD358
Authors: Kepler, S. O.; Nather, R. E.; Winget, D. E.; Nitta,
   A.; Kleinman, S. J.; Metcalfe, T.; Sekiguchi, K.; Jiang, Xiaojun;
   Sullivan, D.; Sullivan, T.; Janulis, R.; Meistas, E.; Kalytis, R.;
   Krzesinski, J.; Ogoza, W.; Zola, S.; O'Donoghue, D.; Romero-Colmenero,
   E.; Martinez, P.; Dreizler, S.; Deetjen, J.; Nagel, T.; Schuh,
   S. L.; Vauclair, G.; Ning, Fu Jian; Chevreton, M.; Solheim, J. -E.;
   Gonzalez Perez, J. M.; Johannessen, F.; Kanaan, A.; Costa, J. E.;
   Murillo Costa, A. F.; Wood, M. A.; Silvestri, N.; Ahrens, T. J.; Jones,
   A. K.; Collins, A. E.; Boyer, M.; Shaw, J. S.; Mukadam, A.; Klumpe,
   E. W.; Larrison, J.; Kawaler, S.; Riddle, R.; Ulla, A.; Bradley, P.
Bibcode: 2003A&A...401..639K
Altcode: 2003astro.ph..1477K
  We report 323 hours of nearly uninterrupted time series photometric
  observations of the DBV star GD 358 acquired with the Whole Earth
  Telescope (WET) during May 23rd to June 8th, 2000. We acquired more
  than 232,000 independent measurements. We also report on 48 hours of
  time-series photometric observations in Aug 1996. We detected the
  non-radial g-modes consistent with degree ℓ=1 and radial order 8
  to 20 and their linear combinations up to 6th order. We also detect,
  for the first time, a high amplitude ℓ=2 mode, with a period of 796
  s. In the 2000 WET data, the largest amplitude modes are similar to
  those detected with the WET observations of 1990 and 1994, but the
  highest combination order previously detected was 4th order. At one
  point during the 1996 observations, most of the pulsation energy
  was transferred into the radial order k=8 mode, which displayed a
  sinusoidal pulse shape in spite of the large amplitude. The multiplet
  structure of the individual modes changes from year to year, and
  during the 2000 observations only the k=9 mode displays clear normal
  triplet structure. Even though the pulsation amplitudes change on
  timescales of days and years, the eigenfrequencies remain essentially
  the same, showing the stellar structure is not changing on any dynamical
  timescale. <P />Tables \ref{j96} to \ref{journal2} and \ref{combination}
  and Figs. \ref{gd358lc1}, \ref{dftchange}, \ref{an34dft}, \ref{pkh},
  \ref{k16} and \ref{deltap8} are available only in the electronic form
  at http://www.edpsciences.org

Title: Spectral analysis of sdB stars from the Hamburg Quasar Survey
Authors: Edelmann, H.; Heber, U.; Hagen, H. -J.; Lemke, M.; Dreizler,
   S.; Napiwotzki, R.; Engels, D.
Bibcode: 2003A&A...400..939E
Altcode: 2003astro.ph..1602E
  We present the results of a spectral analysis of a large sample of
  subdwarf B stars selected from follow-up observations of candidates
  from the Hamburg Quasar Survey. Fundamental parameters (effective
  temperature, gravity, and helium abundance) were determined by
  matching synthetic line profiles calculated from model atmospheres
  to all hydrogen and helium absorption lines present in the observed
  optical spectra. The derived helium abundances are compared with the
  atmospheric parameters to search for possible trends. We discovered a
  correlation between the helium abundance and the effective temperature:
  the larger the temperature, the larger the photospheric helium content
  of sdB stars. Additionally, a separation into two sequences of sdB stars
  in the effective temperature - helium abundance plane is detected. We
  compared our analysis results with data from the literature. The
  stars from our sample are found to be somewhat more luminous. This can
  only partly be explained by NLTE effects. Three apparently normal B
  stars were discovered, which could be massive stars far away from the
  galactic plane (7-19 kpc). Radial velocities were measured for 23 stars
  from which we discovered a new radial velocity variable sdB star. <P
  />Based on Observations collected at the German-Spanish Astronomical
  Center (DSAZ), Calar Alto, operated by the Max-Planck-Institut für
  Astronomie Heidelberg jointly with the Spanish National Commission
  for Astronomy. <P />Table 4 is only available in electronic form at
  the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or
  via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/400/939

Title: VizieR Online Data Catalog: Stellar parameters of 115 HQS
    sdB stars (Edelmann+, 2003)
Authors: Edelmann, H.; Heber, U.; Hagen, H. -J.; Lemke, M.; Dreizler,
   S.; Napiwotzki, R.; Engels, D.
Bibcode: 2003yCat..34000939E
Altcode:
  We present the results of a spectral analysis of a large sample of
  subdwarf B stars selected from follow-up observations of candidates
  from the Hamburg Quasar Survey. Table 4 summarizes the results
  (effective temperatures, gravities, and helium abundances) of our
  analysis. Additionally, the equatorial and galactical coordinates,
  the B magnitudes and extinctions, the derived radial velocities,
  the absolute visual magnitudes, the distances from earth and from
  the galactic plane, and the references are given for all programme
  stars. <P />(3 data files).

Title: FUSE Spectroscopy of the Two Prototype White Dwarfs With
    Signatures of a Super-hot Wind
Authors: Werner, K.; Dreizler, S.; Kruk, J. W.; Sitko, M. L.
Bibcode: 2003ASIB..105..171W
Altcode: 2003whsw.conf..171W; 2002astro.ph..8506W; 2003whdw.conf..171W
  The O VIII phenomenon describes the occurrence of ultra-high ionization
  absorption lines of the CNO elements (e.g. O VIII, N VII, C VI, and
  even Ne X) in the optical spectra hot of DO WDs.

Title: Temperature Correction Schemes
Authors: Dreizler, S.
Bibcode: 2003ASPC..288...69D
Altcode: 2003sam..conf...69D
  The pro and contra for using temperature correction are discussed
  on the basis of our linearization scheme and our implementation of
  an Unsöld-Lucy temperature correction. I will show the improvements
  which partly overcome the typical weakness of the UL-scheme as well
  as our generalization to non-LTE.

Title: FUSE Observations of the Central Star of Abell 78
Authors: Werner, K.; Dreizler, S.; Koesterke, L.; Kruk, J. W.
Bibcode: 2003IAUS..209..239W
Altcode: 2002astro.ph..1280W
  FUSE high resolution spectra of two PG1159 type central stars (K1-16
  and NGC 7094) have revealed an unexpected iron deficiency of at least
  1 or 2 dex (Miksa et al. 2002). Here we present early results of FUSE
  spectroscopy of the CSPN Abell 78. It is shown that iron is strongly
  deficient in this star, too.

Title: TRIPP: An Aperture Photometry Package for the Reduction of
    CCD Time Series Images
Authors: Schuh, S. L.; Dreizler, S.; Deetjen, J. L.; Göhler, E.
Bibcode: 2003BaltA..12..167S
Altcode: 2003OAst...12..167S
  TRIPP is an aperture photometry program designed with the purpose of
  extracting light curves from large sets of similar CCD frames typically
  obtained during time-resolved photometric monitoring campaigns such
  as, for example, WET runs. We describe its properties and usage
  with an emphasis on where the functionality of TRIPP may differ from
  similar programs, and try to outline both its strengths as well as
  the non-trivial issues where difficulties may arise.

Title: NLTE Spectral Analysis of Iron Group Elements in the Hot
    Subluminous O-star BD+28° 4211
Authors: Ramspeck, M.; Haas, S.; Napiwotzki, R.; Heber, U.; Deetjen,
   J.; Dreizler, S.
Bibcode: 2003ASPC..288..161R
Altcode: 2003sam..conf..161R
  An analysis of UV spectra of BD+28<SUP>circ</SUP>4211 obtained with
  the STIS spectrograph onboard the HST is presented. The spectral
  analysis is based on NLTE model calculation, which deal with the
  lineblanketing of iron group elements in great detail. Improved model
  atoms for iron group elements were set up and new interband cross
  sections were calculated. Comparison with observation allowed, Mn and
  Cr lines to be identified for the first time. The abundances of Fe,
  Ni, Cr and Mn are determined and point to the presence of diffusion
  processes in the atmosphere of BD+28<SUP>circ</SUP>4211.

Title: Analysis of FUSE and IUE spectra of the sdOB star EC11481-2303
Authors: Hammer, N. J.; Deetjen, J. L.; Dreizler, S.; Werner, K.;
   Kruk, J. W.
Bibcode: 2003ASIB..105..103H
Altcode: 2003whdw.conf..103H; 2003whsw.conf..103H
  No abstract at ADS

Title: Towards asteroseismology of the non-radial pulsating sdB star
    PG 1605+072
Authors: Falter, S.; Heber, U.; Dreizler, S.; Schuh, S. L.; Cordes, O.
Bibcode: 2003ASIB..105...73F
Altcode: 2003whdw.conf...73F; 2002astro.ph.12489F; 2003whsw.conf...73F
  The recently discovered new class of sdB pulsators (sdBV) offers a
  powerful possibility for the investigation of their interior and
  thus their evolutionary history. The first step towards applying
  asteroseismologic tools is the identification of pulsation modes. We
  reoport on simultaneous spectroscopic and multi-band photometric time
  series observations of PG 1605+072 and analyse its radial velocity
  and light curve.

Title: Vertical Structures and Spectra of Accretion Disks in
    Symbiotic Stars
Authors: Nagel, T.; Dreizler, S.; Werner, K.
Bibcode: 2003ASPC..303..482N
Altcode: 2003ssps.conf..482N
  No abstract at ADS

Title: Stellar Atmosphere and Accretion Disk Models for the Hot
    Component in Symbiotic Stars
Authors: Werner, K.; Deetjen, J. L.; Dreizler, S.; Nagel, T.; Rauch, T.
Bibcode: 2003ASPC..303..303W
Altcode: 2003ssps.conf..303W; 2002astro.ph..8199W
  We describe our NLTE codes which allow the computation of synthetic
  spectra of hot stars and accretion disks. They can be combined to
  compute ionizing fluxes from the hot component in symbiotic stars.

Title: Calculating Vertical Structures and Spectra of Accretion
    Disks with the New Code AcDc
Authors: Nagel, T.; Dreizler, S.; Werner, K.
Bibcode: 2003ASPC..288..641N
Altcode: 2003sam..conf..641N
  We present a new code to calculate the vertical structure of accretion
  disks in cataclysmic variables. The disk is divided into concentric
  rings, each ring is treated like an independent plane-parallel
  radiating slab. We first calculate a gray LTE model and then a NLTE
  model of the ring. Finally we integrate over all ring spectra to get the
  spectrum of the full disk for a specific inclination angle. The system
  of hydrostatic and radiative equilibrium, atomic level populations
  and particle conservation is solved consistently with the radiative
  transfer. <P />This allows to calculate detailed theoretical spectra
  of accretion disks. Comparison with observations will allow to derive
  radial temperature distribution, mass accretion rate, viscosity and
  chemical composition. We also plan to compare our vertical structures
  to those of hydrodynamic simulations in order to estimate the influence
  of a detailed radiation transport on the stratification.

Title: Transfer of Polarized Radiation - Practical Experience with
    the Accelerated Lambda Iteration Method
Authors: Deetjen, J. L.; Dreizler, S.; Jordan, S.; Werner, K.
Bibcode: 2003ASPC..288..617D
Altcode: 2003sam..conf..617D
  Neutron stars and some of the white dwarfs have magnetic fields. The
  light emitted by these stars is polarized and can be characterized
  by the four Stokes components I, Q, U, and V. Therefore the polarized
  radiation transport equation differs significantly from the non-magnetic
  case. It is a system of linear differential equations coupled in
  I, Q, U, and V with depth dependent opacities and magneto-optical
  parameters. The most potential method, the accelerated lambda iteration,
  is presented in detail and practical experiences calculating neutron
  star atmospheres are reported.

Title: Modeling C/O/Ne Dominated Accretion in Ultracompact X-ray
    Binaries
Authors: Werner, K.; Nagel, T.; Dreizler, S.; Rauch, T.
Bibcode: 2003gcfe.confE..35W
Altcode:
  No abstract at ADS

Title: Calculating spectra of accretion disks in AM CVn systems
Authors: Nagel, T.; Dreizler, S.; Werner, K.
Bibcode: 2003ASIB..105..357N
Altcode: 2003whdw.conf..357N; 2003whsw.conf..357N
  No abstract at ADS

Title: Discovery of A New Class of Pulsating Stars: Gravity-Mode
    Pulsators among Subdwarf B Stars
Authors: Green, E. M.; Fontaine, G.; Reed, M. D.; Callerame, K.;
   Seitenzahl, I. R.; White, B. A.; Hyde, E. A.; Østensen, R.; Cordes,
   O.; Brassard, P.; Falter, S.; Jeffery, E. J.; Dreizler, S.; Schuh,
   S. L.; Giovanni, M.; Edelmann, H.; Rigby, J.; Bronowska, A.
Bibcode: 2003ApJ...583L..31G
Altcode:
  During the course of an ongoing CCD monitoring program to investigate
  low-level light variations in subdwarf B (sdB) stars, we have
  serendipitously discovered a new class of low-amplitude, multimode sdB
  pulsators with periods of the order of an hour. These periods are more
  than a factor of 10 longer than those of previously known multimode
  sdB pulsators (EC 14026 stars), implying that they are due to gravity
  modes rather than pressure modes. The longer period pulsators are found
  only among cooler sdB stars, where they are surprisingly common. The
  iron opacity instability that drives the short-period EC 14026 stars
  is effective only in hot sdB stars, leaving the driving mechanism
  for the deeper gravity modes in cool sdB stars currently unknown. We
  present the first observational results for our newly identified sdB
  variables and discuss possible implications.

Title: FUSE Spectra of DO White Dwarfs
Authors: Dreizler, S.; Werner, K.; Kruk, J. W.
Bibcode: 2003ASIB..105..135D
Altcode: 2003whsw.conf..135D; 2003whdw.conf..135D
  FUSE observations of DO white dwarfs allow to determine their
  photospheric abundances of trace elements (e.g. C, N, O, H, Fe,
  Ni,...). FUSE spectroscopy is ideal for this purpose since the FUV
  allows to explore a large variety of line transitions of various
  elements which are not detectable in existing optical or UV spectra of
  the targets. We present our analysis with non-LTE metal line blanketed
  model atmospheres. The results will be compared to our newly developed,
  self-consistent diffusion/radiative levitation calculations under
  non-LTE conditions. The observed metal abundances will serve as
  bench-marks for such kind of new calculations.

Title: Metal abundances in PG1159 stars from Chandra and FUSE
    spectroscopy
Authors: Werner, K.; Deetjen, J. L.; Dreizler, S.; Rauch, T.; Barstow,
   M. A.; Kruk, J. W.
Bibcode: 2003ASIB..105..117W
Altcode: 2002astro.ph..8505W; 2003whsw.conf..117W; 2003whdw.conf..117W
  We investigate FUSE spectra of three PG1159 stars and do not find any
  evidence for iron lines. From a comparison with NLTE models we conclude
  a deficiency of 1--1.5 dex. We speculate that iron was transformed
  into heavier elements. A soft X-ray Chandra spectrum of the unique H-
  and He-deficient star H1504+65 is analyzed. We find high neon and
  magnesium abundances and confirm that H1504+65 is the bare core of
  either a C-O or a O-Ne-Mg white dwarf.

Title: Improved results for equilibrium abundances from diffusion
    calculations
Authors: Schuh, S. L.; Dreizler, S.; Deetjen, J. L.
Bibcode: 2003ASIB..105..147S
Altcode: 2003whsw.conf..147S; 2003whdw.conf..147S
  No abstract at ADS

Title: Computation of Element Diffusion in Non-LTE Stellar Atmosphere
    Models
Authors: Schuh, S. L.; Dreizler, S.
Bibcode: 2003ASPC..288..633S
Altcode: 2003sam..conf..633S
  No abstract at ADS

Title: Temperature Scale and Iron Abundances of Very Hot Central
    Stars of Planetary Nebulae (invited review)
Authors: Werner, K.; Deetjen, J. L.; Dreizler, S.; Rauch, T.; Kruk,
   J. W.
Bibcode: 2003IAUS..209..169W
Altcode: 2002astro.ph..2012W
  The determination of effective temperatures of very hot central stars
  (Teff&gt;70000K) by model atmosphere analyses of optical H and He
  line profiles is afflicted with considerable uncertainty, primarily
  due to the lack of neutral helium lines. Ionization balances of
  metals, accessible only with UV lines, allow more precise temperature
  estimates. The potential of iron lines is pointed out. At the same time
  iron and other metal abundances, hardly investigated until today, may be
  derived from UV spectra. We describe recent HST spectroscopy performed
  for this purpose. A search for iron lines in FUV spectra of the hottest
  H-deficient central stars (PG1159-type, Teff&gt;100000K) taken with FUSE
  was unsuccessful. The derived deficiency is interpreted in terms of
  iron depletion due to n-capture nucleosynthesis in intershell matter,
  which is now exposed at the stellar surface as a consequence of a late
  He shell flash.

Title: Modeling He-rich Disks in Am CVn Binaries
Authors: Nagel, T.; Dreizler, S.; Rauch, T.; Werner, K.
Bibcode: 2003gcfe.confE..34N
Altcode:
  No abstract at ADS

Title: Preliminary results of the WET Xcov22 campaign at Calar
    Alto Observatory
Authors: Schuh, S. L.; Nagel, T.; Deetjen, J. L.; Dreizler, S.;
   Handler, G.; O'Brien, M. S.; Riddle, R.; Hürkal, Ö.; Pakstiene, E.;
   Klumpe, E.; Lawrence, T.; Vuckovic, M.; Zola, S.; Kawaler, S.; Kanaan,
   A.; Giovannini, O.; Kepler, S. O.; Mukadam, A.; Provencal, J.; Nitta,
   A.; Shipman, H.; Mullally, F.; Grauer, A.; Wood, M. A.; Bradley, P. A.;
   Kilic, M.; Sekiguchi, K.; Crowe, R.; Sullivan, D.; Rosen, R.; Clemens,
   C.; Jiang, Xiaojun; Janulis, R.; O'Donoghue, D.; Ogloza, W.; Baran, A.;
   Silvotti, R.; Marinoni, S.; Vauclair, G.; Dolez, N.; Chevreton, M.;
   Gonzalez, J. M.; Solheim, J. -E.; Ulla, A.; Burleigh, M.; Good, S.;
   Metcalfe, T.; da Costa, A. F. M.; Costa, J. E. S.; Kim, S. -L.; Lee,
   H.; Sergeev, A.; Akan, C.; Cakirli, Ö.; Paparo, M.; Viraghalmy, G.
Bibcode: 2003ASIB..105..263S
Altcode: 2003whdw.conf..263S; 2003whsw.conf..263S
  No abstract at ADS

Title: WET Observations of GD 358 in 2000
Authors: Kepler, S. O.; Nather, E. R.; Winget, D. E.; Nitta, A.;
   Kleinman, S. J.; Metcalfe, T.; Sekiguchi, K.; Jiang, Xiaojun;
   Sullivan, D.; Sullivan, T.; Janulis, R.; Meištas, E. G.; Kalytis,
   R.; Krzesiński, J.; Ogłoza, W.; Zola, S.; O'Donoghue, D.;
   Romero-Colmenero, E.; Martinez, P.; Dreizler, S.; Deetjen, J.;
   Nagel, T.; Schuh, S. L.; Vauclair, G.; Fu, J. N.; Chevreton, M.;
   Solheim, J. -E.; Gonzalez Perez, J. M.; Johannessen, F.; Kanaan,
   A.; Costa, J. E.; Murillo Costa, A. F.; Wood, M. A.; Silvestri, N.;
   Ahrens, T. J.; Jones, A. Kyle; Collins, A. E.; Boyer, M.; Shaw, J. S.;
   Mukadam, A. S.; Klumpe, E. W.; Larrison, J.; Kawaler, S. D.; Riddle,
   R. L.; Ulla, A.; Bradley, P.
Bibcode: 2003BaltA..12...45K
Altcode: 2003OAst...12...45K
  We report on the 323 hours of nearly uninterrupted time series
  photometric observations of the DBV star GD 358 acquired with the Whole
  Earth Telescope (WET) during May 23 to June 8, 2000. We acquired more
  than 232000 independent measurements and detected the non-radial g-modes
  consistent with degree l=1 and radial order 8 to 20 and their linear
  combinations up to 6th order. We also detect, for the first time,
  a high amplitude l=2 mode, with a period of 796 s. In the 2000 WET
  data, the largest amplitude modes are similar to those detected with
  the WET observations of 1990 and 1994, but the highest combination
  order previously detected was 4th order.

Title: Stratified NLTE Model Atmospheres for Hot Stars
Authors: Dreizler, S.; Schuh, S. L.
Bibcode: 2003IAUS..210...33D
Altcode:
  No abstract at ADS

Title: Photometric and Spectroscopic Monitoring of the sdBV star PG
1605+072: The Multi-Site Spectroscopic Telescope (MSST) Project
Authors: Heber, U.; Dreizler, S.; Schuh, S. L.; O'Toole, S.; Jeffery,
   C. S.; Falter, S.; Woolf, V.; Ahmad, A.; Billeres, M.; Charpinet,
   S.; Cordes, O. -M.; For, B. -Q.; Green, E.; Hyde, E. A.; Jacob, A.;
   Kjeldsen, H.; Kleinman, S.; Krzesinski, J.; Lopes, I.; Marinoni, S.;
   Mauch, T.; Nitta, A.; O'Donoghue, D.; Østensen, R.; Pollacco, D.;
   Pereira, R.; Pereira, T.; Reed, M. D.; Silvotti, R.; Townsend, R.;
   Vuckovic, M.; White, B. A.; Jiang, Xiaojun
Bibcode: 2003ASIB..105..105H
Altcode: 2003whdw.conf..105H; 2002astro.ph.12447H; 2003whsw.conf..105H
  A small fraction of subluminous B stars show short-period, multiperiodic
  light variations and form the new class of pulsating star known as EC
  14026 variables, after the prototype. The Multi-Site Spectroscopic
  Telescope (MSST) is a virtual instrument and is also the name of
  a collaboration that aims to open up a new observational window to
  provide access to a mode identification for and an asteroseismological
  analysis of the pulsating sdB star PG 1605+072. Although the primary
  aim is to obtain time resolved spectroscopy it also includes the most
  extended photometric monitoring campaign for PG 1605+072.

Title: PG 1605+072 in WET XCov22:  Support for the Multi Site
    Spectroscopic Telescope
Authors: Schuh, S. L.; Heber, U.; Dreizler, S.; O'Toole, S.; Jeffery,
   C. S.; Falter, S.; Woolf, V. M.; Riddle, R. L.; Handler, G.; Hürkal,
   Ö.; Pakštiene, E.; Klumpe, E. W.; Laurance, T.; Vuckovic, M.;
   Zoa, S.; Kawaler, S. D.; Kanaan, A.; Monteiro, H.; Giovannini, O.;
   Kepler, S. O.; Mukadam, A.; Provencal, J. L.; Nitta, A.; Shipman, H.;
   Mullally, F.; Grauer, A.; Wood, M. A.; Bradley, P. A.; Kilic, M.;
   Sekiguchi, K.; Crowe, R.; Sullivan, D. J.; Rosen, R.; Clemens, C.;
   Jiang, Xiaojun; Janulis, R.; O'Donoghue, D.; Ogloza, W.; Baran, A.;
   Silvotti, R.; Marinoni, S.; Vauclair, G.; Dolez, N.; Chevreton, M.;
   Deetjen, J. L.; Nagel, T.; González Pérez, J. M.; Solheim, J. -E.;
   Østensen, R.; Ulla, A.; Burleigh, M.; Good, S.; Metcalfe, T. S.; da
   Costa, A. F. M.; Costa, J. E. S.; O'Brien, M. S.; Kim, S. -L.; Lee,
   H.; Sergeev, A.; Akan, C.; Cakirli, Ö.; Paparo, M.; Viraghalmy, G.
Bibcode: 2003BaltA..12...55S
Altcode: 2003OAst...12...55S
  The Multi-site Spectroscopic Telescope is a virtual instrument and
  the name of a collaboration that opens up a new observational window
  by combining continuous observations of spectroscopic variations and
  simultaneous photometric monitoring. This constitutes an enormous
  observational effort, but in return promises to finally provide access
  to a mode identification for and an asteroseismological analysis
  of the pulsating sdB star PG 1605+072. Multi-Site Spectroscopic
  Telescope observations for this object have been secured during a
  large coordinated campaign in May and June of the year 2002. The
  frequency resolution and coverage of the photometric time series has
  been noticeably enhanced by a significant contribution from the Whole
  Earth Telescope, which was used to observe PG 1605+072 as an alternate
  target during the WET XCov22 campaign, also conducted in May 2002. This
  paper briefly outlines the motivation for the MSST project and tries
  to give a first assessment of the overall quality of the data obtained,
  with a focus on the Whole Earth Telescope observations.

Title: WET Observations of PG 1159--035
Authors: Costa, J. E. S.; Kepler, S. O.; Winget, D. E.; O'Brien,
   M. S.; Bond, H. E.; Kawaler, S. D.; Dreizler, S.
Bibcode: 2003BaltA..12...23C
Altcode: 2003OAst...12...23C
  PG 1159-035 has been observed with the Whole Earth Telescope on XCov3,
  9, 19 and 22. In this work we present a brief summary of the campaigns.

Title: Model Photospheres with Accelerated Lambda Iteration
Authors: Werner, K.; Deetjen, J. L.; Dreizler, S.; Nagel, T.; Rauch,
   T.; Schuh, S. L.
Bibcode: 2003ASPC..288...31W
Altcode: 2002astro.ph..9535W; 2003sam..conf...31W
  We review the computational procedure to construct classical
  line-blanketed NLTE model atmospheres with the ALI method. In detail
  we discuss: Approximate Lambda Operators, fast solution techniques
  for non-linear rate equations, pre-conditioning of rate equations,
  super-level approach for heavy metal line-blanketing. Most recent
  successes and failures in applications are shortly presented.

Title: The Rotational Velocity of Helium-rich Pre-White Dwarfs
Authors: Rauch, T.; Koeper, S.; Dreizler, S.; Werner, K.; Heber, U.;
   Reid, I. N.
Bibcode: 2002astro.ph.12163R
Altcode:
  Previous investigations on hydrogen-rich white dwarfs generally
  yield only very small rotational velocities (v_rot sin i). We have
  analyzed line profiles in high-resolution optical spectra of eight
  hydrogen-deficient (pre-) white dwarfs and find deviations from the
  dominant Stark line broadening in five cases which, interpreted as an
  effect of stellar rotation, indicate projected rotational velocities of
  40 - 70 km/sec. For the three least luminous stars upper limits of v_rot
  sin i = 15 - 25 km/sec could be derived only. The resulting velocities
  correlate with luminosity and mass. However, since the mass-loss rate is
  correlated to the luminosity of a star, the observed line profiles may
  be affected by a stellar wind as well. In the case of RX J2117.1+3412,
  this would solve discrepancies to results of pulsational modeling
  (v_rot sin i ~ 0).

Title: Spectroscopic analyses of the ``blue hook'' stars in omega
Centauri: A test of the late hot flasher scenario
Authors: Moehler, S.; Sweigart, A. V.; Landsman, W. B.; Dreizler, S.
Bibcode: 2002A&A...395...37M
Altcode: 2002astro.ph..9028M
  omega Cen contains the largest population of very hot horizontal
  branch (HB) stars known in a globular cluster. Recent UV observations
  (Whitney et al. \cite{whro98}; D'Cruz et al. \cite{dcoc00}) show a
  significant population of hot stars below the zero-age horizontal branch
  (``blue hook'' stars), which cannot be explained by canonical stellar
  evolution. Stars which suffer unusually large mass loss on the red giant
  branch and thus experience the helium core flash while descending the
  white dwarf cooling curve could populate this region. Theory predicts
  that these ``late hot flashers'' should show higher temperatures than
  the hottest canonical HB stars and should have helium- and carbon-rich
  atmospheres. We obtained and analysed medium resolution spectra of a
  sample of blue hook stars to derive their atmospheric parameters. The
  blue hook stars are indeed both hotter (T<SUB>eff</SUB> &gt;=35 000
  K) and more helium-rich than classical extreme HB stars. In addition
  we find indications for a large enhancement of the carbon abundance
  relative to the cluster abundance.

Title: Spectral types of planetary host star candidates: Two new
    transiting planets?
Authors: Dreizler, S.; Rauch, T.; Hauschildt, P.; Schuh, S. L.; Kley,
   W.; Werner, K.
Bibcode: 2002A&A...391L..17D
Altcode: 2002astro.ph..7192D
  Recently, 46 low-luminosity object transits were reported from
  the Optical Gravitational Lensing Experiment. Our follow-up
  spectroscopy of the 16 most promising candidates provides a spectral
  classification of the primary. Together with the radius ratio from
  the transit measurements, we derived the radii of the low-luminosity
  companions. This allows to examine the possible sub-stellar nature
  of these objects. Fourteen of them can be clearly identified as
  low-mass stars. Two objects, <ASTROBJ>OGLE-TR-03</ASTROBJ> and
  <ASTROBJ>OGLE-TR-10</ASTROBJ> have companions with radii of 0.15
  R_sun which is very similar to the radius of the transiting planet HD
  209458 B. The planetary nature of these two objects should therefore
  be confirmed by dynamical mass determinations.

Title: The temporal spectrum of the sdB pulsating star HS 2201+2610
    at 2 ms resolution
Authors: Silvotti, R.; Janulis, R.; Schuh, S. L.; Charpinet, S.;
   Oswalt, T.; Silvestri, N.; Gonzalez Perez, J. M.; Kalytis, R.;
   Meištas, E.; Ališauskas, D.; Marinoni, S.; Jiang, X. J.; Reed, M. D.;
   Riddle, R. L.; Bernabei, S.; Heber, U.; Bärnbantner, O.; Cordes, O.;
   Dreizler, S.; Goehler, E.; Østensen, R.; Bochanski, J.; Carlson, G.
Bibcode: 2002A&A...389..180S
Altcode:
  In this article we present the results of more than 180 hours of
  time-series photometry on the low gravity (log g=5.4, T<SUB>eff</SUB>=29
  300 K, log He/H=-3.0 by number) sdB pulsating star HS 2201+2610,
  obtained between September 2000 and August 2001. The temporal
  spectrum is resolved and shows 5 close frequencies: three main
  signals at 2860.94, 2824.10 and 2880.69 mu Hz, with amplitudes of
  about 1%, 0.5% and 0.1% respectively, are detected from single run
  observations; two further peaks with very low amplitude (&lt;0.07%) at
  2738.01 and 2921.82 mu Hz are confirmed by phase analysis on several
  independent runs. Due to the small number of detected frequencies,
  it is not possible to obtain a univocal identification of the excited
  modes and perform a detailed seismological analysis of the star. No
  clear signatures of rotational splitting are seen. Nevertheless,
  the observed period spectrum is well inside the excited period window
  obtained from pulsation calculations with nonadiabatic models having
  effective temperature and surface gravity close to the spectroscopic
  estimates. Due to its relatively simple temporal spectrum, HS 2201+2610
  is a very good candidate for trying to measure the secular variation of
  the pulsation periods in time. With this purpose a long-term monitoring
  of the star was started. The results of the first 11 months show
  amplitude variations up to ~ 20% on time-scales of months, which are
  probably real, and allow us to measure the pulsation frequencies with
  an unprecedented 0.02 mu Hz resolution. Based on observations obtained
  at the following telescopes: Loiano 1.5 m (Bologna Astronomical
  Observatory), Moletai 1.65 m (Institute of Theoretical Physics
  and Astronomy, Vilnius), Calar Alto 2.2 and 1.2 m (German-Spanish
  Astronomical Center operated by the Max-Plank-Institute für Astronomie
  Heidelberg jointly with the Spanish National Commission for Astronomy),
  SARA 0.9 m (Southeastern Association for Research in Astronomy, at Kitt
  Peak, Arizona), Tenerife 0.8 m (Instituto de Astrofisica de Canarias),
  NOT 2.6 m (operated on the island of La Palma jointly by Denmark,
  Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del
  Roque de los Muchachos of the Instituto de Astrofisica de Canarias),
  Beijing 0.85 m (Beijing Astronomical Observatory), Fick 0.6 m (Iowa
  State University), Wendelstein 0.8 m (University of Munich).

Title: Iron abundance in hot hydrogen-deficient central stars and
    white dwarfs from FUSE, HST, and IUE spectroscopy
Authors: Miksa, S.; Deetjen, J. L.; Dreizler, S.; Kruk, J. W.; Rauch,
   T.; Werner, K.
Bibcode: 2002A&A...389..953M
Altcode: 2002astro.ph..5058M
  We present a first systematic investigation of the iron abundance
  in very hot (T<SUB>eff</SUB> &gt;= 50 000 K) hydrogen-deficient
  post-AGB stars. Our sample comprises 16 PG 1159 stars and four DO white
  dwarfs. We use recent FUSE observations as well as HST and IUE archival
  data to perform spectral analyses with line blanketed NLTE model
  atmospheres. Iron is not detected in any PG 1159 star. In most cases
  this is compatible with a solar iron abundance due to limited quality of
  HST and IUE data, although the tendency to an iron underabundance may be
  recognized. However, the absence of iron lines in excellent FUSE spectra
  suggests an underabundance by at least 1 dex in two objects (K 1-16,
  NGC 7094). A similar result has been reported recently in the [WC]-PG
  1159 transition object Abell 78 (Werner et al. \cite{Werner2002}). We
  discuss dust fractionation and s-process neutron-captures as possible
  origins. We also announce the first identification of sulfur in PG
  1159 stars. Based on observations obtained with the Far Ultraviolet
  Spectroscopic Explorer (FUSE), the Hubble Space Telescope (HST),
  and the International Ultraviolet Explorer (IUE).

Title: Is RX J1856.5-3754 a Quark Star?
Authors: Drake, Jeremy J.; Marshall, Herman L.; Dreizler, Stefan;
   Freeman, Peter E.; Fruscione, Antonella; Juda, Michael; Kashyap,
   Vinay; Nicastro, Fabrizio; Pease, Deron O.; Wargelin, Bradford J.;
   Werner, Klaus
Bibcode: 2002ApJ...572..996D
Altcode: 2002astro.ph..4159D
  Deep Chandra Low Energy Transmission Grating and High Resolution Camera
  spectroscopic observations of the isolated neutron star candidate RX
  J1856.5-3754 have been analyzed to search for metallic and resonance
  cyclotron spectral features and for pulsation behavior. As found
  from earlier observations, the X-ray spectrum is well represented
  by an ~60 eV (7×10<SUP>5</SUP> K) blackbody. No unequivocal
  evidence of spectral line or edge features has been found, arguing
  against metal-dominated models. The data contain no evidence for
  pulsation, and we place a 99% confidence upper limit of 2.7% on
  the unaccelerated pulse fraction over a wide frequency range from
  10<SUP>-4</SUP> to 100 Hz. We argue that the derived interstellar
  medium neutral hydrogen column density of 8×10<SUP>19</SUP>cm<SUP>-
  2</SUP>&lt;=N<SUB>H</SUB>&lt;=1.1×10<SUP>20</SUP> cm<SUP>-2</SUP>
  favors the larger distance from two recent Hubble Space Telescope
  parallax analyses, placing RX J1856.5-3754 at ~140 pc instead of ~60
  pc and in the outskirts of the R CrA dark molecular cloud. That such
  a comparatively rare region of high interstellar matter (ISM) density
  is precisely where an isolated neutron star reheated by accretion
  of ISM would be expected is either entirely coincidental or current
  theoretical arguments excluding this scenario for RX J1856.5-3754
  are premature. Taken at face value, the combined observational
  evidence-a lack of spectral and temporal features and an implied
  radius of R<SUB>∞</SUB>=3.8-8.2 km that is too small for current
  neutron star models-points to a more compact object, such as allowed
  for quark matter equations of state.

Title: HS0702+6043 - A new large amplitude sdB variable at the cool
    end of the instability region
Authors: Dreizler, S.; Schuh, S. L.; Deetjen, J. L.; Edelmann, H.;
   Heber, U.
Bibcode: 2002A&A...386..249D
Altcode:
  We report on time series photometry of hot sdB stars from the
  Hamburg Schmidt survey carried out at the Calar Alto 1.23 m and
  2.2 m telescopes. Among 14 spectroscopically selected candidates we
  detected oscillations in the sdB star <ASTROBJ>HS0702+6043</ASTROBJ>
  with a period of 363 s and an amplitude of 29 mmag which is among
  the largest amplitude observed in sdBV stars. A second period of
  382 s with a significantly smaller amplitude (3.8 mmag) might be
  present. Our NLTE model atmosphere analysis of the time-averaged
  optical spectra, obtained at the Calar Alto 3.5 m telescope, indicates
  that <ASTROBJ>HS0702+6043</ASTROBJ> has T<SUB>eff</SUB>=28 400 K and
  log g=5.35. This places the star at the cool end of the theoretical
  sdBV instability strip (EC 14026 stars). Among the other thirteen
  sdB stars we confirmed the variablity of the previously discovered
  sdBV <ASTROBJ>HS0815+4243</ASTROBJ> and identified twelve stars to be
  stable, for which we give upper limits for light variations. Based on
  observations collected at the German-Spanish Astronomical Center, Calar
  Alto, operated by the Max-Planck-Institut für Astronomie Heidelberg
  jointly with the Spanish National Commission for Astronomy.

Title: Analysis of the FUSE spectrum of the sdOB EC 11481-2303.
Authors: Hammer, N.; Deetjen, J. L.; Dreizler, S.; Werner, K.; Kruk,
   J. W.
Bibcode: 2002AGAb...19R..96H
Altcode:
  No abstract at ADS

Title: PG 1325+101 and PG 2303+019: Two new large amplitude subdwarf
    B pulsators
Authors: Silvotti, R.; Østensen, R.; Heber, U.; Solheim, J. -E.;
   Dreizler, S.; Altmann, M.
Bibcode: 2002A&A...383..239S
Altcode:
  We report the detection of short period oscillations in the sdB stars
  PG 1325+101 (B=13.8) and PG 2303+019 (alias HS 2303+0152, B=16.0) from
  time-series photometry made at the Nordic Optical Telescope of a sample
  of 21 candidates. Both stars are multi-mode pulsators with at least
  three distinct periods in the range 100-140 s, and relatively large
  amplitudes up to 2.6 and 1.6% respectively. Moreover PG 1325+101 shows
  the shortest pulsation period ever registered among sdBV stars, 68.9 s,
  which corresponds to the first harmonic of the main signal. Following
  previous temperature and gravity determinations for PG 1325+101
  (T<SUB>eff</SUB> = 34 500 K, log g=6.1) and our NLTE model atmosphere
  analysis for PG 2303+019 (T<SUB>eff</SUB> = 35 200 K, log g=5.7), both
  stars are well inside the theoretical sdBV instability strip. Based
  on observations obtained at the Nordic Optical Telescope, operated on
  the island of La Palma jointly by Denmark, Finland, Iceland, Norway,
  and Sweden, in the Spanish Observatorio del Roque de los Muchachos of
  the Instituto de Astrofisica de Canarias; and at the German-Spanish
  Astronomical Center, Calar Alto, operated by the Max-Plank-Institute
  für Astronomie Heidelberg jointly with the Spanish National Commission
  for Astronomy.

Title: Extremely Faint Blue-tail Stars in ω Centauri
Authors: Moehler, S.; Napiwotzki, R.; Sweigart, A. V.; Landsman,
   W. B.; Dreizler, S.
Bibcode: 2002ASPC..265..247M
Altcode: 2002ocuw.conf..247M
  No abstract at ADS

Title: AcDc -- A new code to calculate vertical structures and
    spectra of accretion disks
Authors: Nagel, T.; Dreizler, S.; Werner, K.
Bibcode: 2002ASPC..261..509N
Altcode: 2002pcvr.conf..509N
  We are developing a new program which computes vertical structures
  and emergent spectra of accretion disks in CVs and AGN. It solves the
  radiation transfer equation together with the NLTE rate equations for
  atomic level populations using an ALI (Accelerated Lambda Iteration)
  scheme. First results are presented.

Title: Spectral types of planetary host star candidates: new
    transiting planets ?
Authors: Dreizler, S.; Rauch, T.; Hauschildt, P.; Schuh, S. L.; Kley,
   W.; Werner, K.
Bibcode: 2002AGAb...19R...6D
Altcode:
  No abstract at ADS

Title: To be or not to be a late hot flasher.
Authors: Moehler, S.; Sweigart, A. V.; Landsman, W. B.; Dreizler, S.
Bibcode: 2002AGAb...19Q.104M
Altcode:
  No abstract at ADS

Title: Equilibrium abundances in hot DA white dwarfs as derived
    from self-consistent diffusion models. I. Analysis of spectroscopic
    EUVE data
Authors: Schuh, S. L.; Dreizler, S.; Wolff, B.
Bibcode: 2002A&A...382..164S
Altcode: 2001astro.ph.11245S
  We present the first analysis of an EUV selected sample of hot DA
  white dwarfs using a new type of atmospheric models. These models
  take into account the interplay between gravitational settling and
  radiative acceleration to predict the chemical stratification from
  an equilibrium between the two forces while self-consistently solving
  for the atmospheric structure. In contrast to atmospheric models with
  the assumption of chemical homogeneity, the number of free parameters
  in the new models is reduced to the effective temperature and surface
  gravity alone. The overall good reproduction of observed EUV spectra
  reveals that these models are able to describe the physical conditions
  in hot DA white dwarf atmospheres correctly. A comparison with previous
  analyses highlights the improvements as well as the limits of our new
  models. Based on observations made with the EUVE Satellite.

Title: The Origin of Hot Subluminous Horizontal-Branch Stars in ω
    Cen and NGC 2808
Authors: Sweigart, A. V.; Brown, T. M.; Moehler, S.; Lanz, T.;
   Landsman, W. B.; Hubeny, I.; Dreizler, S.; Napiwotzki, R.
Bibcode: 2001AAS...19913704S
Altcode: 2001BAAS...33.1512S
  Ultraviolet (UV) observations of the globular clusters ω Cen and NGC
  2808 have revealed an unexpected population of hot subluminous stars
  lying up to 0.7 mag below the extreme horizontal branch (EHB) in the
  UV, which are not explained by canonical stellar models. In order to
  explore the evolutionary status of these stars, we have evolved a set
  of low-mass stars from the main sequence through the helium flash to
  the horizontal branch (HB) for a wide range in the mass loss along the
  red-giant branch (RGB). Stars with the largest mass loss evolve off
  the RGB to high effective temperatures before igniting helium in their
  cores. Our results indicate that the subluminous stars can be explained
  if these stars undergo a late helium flash while descending the white
  dwarf cooling curve. Under these conditions the convection zone produced
  by the helium flash will penetrate into the stellar envelope, thereby
  mixing the envelope hydrogen into the hot helium-burning interior, where
  it is rapidly consumed. Such ``flash-mixed'' stars will have helium-
  and carbon-rich envelopes and will lie at higher effective temperatures
  than the hottest canonical (i.e., unmixed) EHB stars. Using new stellar
  atmospheres, we show that these changes in the envelope abundances
  will suppress the UV flux in the spectra of the flash-mixed stars by
  the amount needed to explain the hot subluminous stars in ω Cen and
  NGC 2808. To test this evolutionary scenario, we have obtained medium
  resolution spectra of a sample of the hottest HB stars in ω Cen. We
  find that these stars are indeed helium-rich compared to classical
  EHB stars and also considerably hotter than the hottest EHB models
  without flash mixing.

Title: Introduction to Volume 322 (5/6) Proceedings of the
    Joint-Discussion #1 and the Mini-Symposia #9 and #10 at the Joint
    European and National Astronomical Meeting (JENAM) for 2001
Authors: Strassmeier, K. G.; Staude, J.; Dreizler, S.
Bibcode: 2001AN....322..271S
Altcode:
  This volume of AN contains the proceedings of the Joint Discussion
  #1 (JD-1) ``Astronomy with Robotic Telescopes: Present and Future
  Projects'' and of the Mini Symposia #9 (MS-9) ``Hot subdwarfs,
  white dwarfs, and low-mass star evolution'', and #10 (MS-10) ``Large
  Telescopes for Solar Physics''. The meetings were held as part of the
  JENAM 2001 conference ``Five Days of Creation. Astronomy with Large
  Telescopes from Ground and Space'' in Munich, Germany, from September
  10 through 15, 2001.

Title: Four new subdwarf B pulsators
Authors: Østensen, R.; Heber, U.; Silvotti, R.; Solheim, J. -E.;
   Dreizler, S.; Edelmann, H.
Bibcode: 2001A&A...378..466O
Altcode:
  We report the detection of short period oscillations in the sdB stars HS
  0039+4302, HS 0444+0408, HS 1824+5745 and HS 2151+0857 from time-series
  photometry made at the Nordic Optical Telescope (NOT) of a sample of
  55 candidates. Hence these four hot subdwarfs are new members of the
  EC 14026 class of pulsating sdB stars. HS 0039+4302 is a multi-mode
  pulsator with at least four distinct periods in the range between 182
  and 234 s, and amplitudes up to 8 mma. HS 0444+0408 shows one dominant
  pulsation at 137 s (A ~ 12 mma) and a second weaker pulsation at 170 s
  (A ~ 3 mma). For HS 1824+5745 we find a single period of 139 s with
  an amplitude of about 5 mma. HS 2151+0857 shows four periods in the
  range 129-151 s with amplitudes between 2 and 5 mma. Our NLTE model
  atmosphere analysis of the time-averaged optical spectra place all
  stars well within the theoretical sdBV instability strip. Based on
  observations obtained at the Nordic Optical Telescope, operated on
  the island of La Palma jointly by Denmark, Finland, Iceland, Norway,
  and Sweden, in the Spanish Observatorio del Roque de los Muchachos of
  the Instituto de Astrofisica de Canarias. }\fnmsep\thanks{ Based on
  observations collected at the German-Spanish Astronomical Center, Calar
  Alto, operated by the Max-Plank-Institute für Astronomie Heidelberg
  jointly with the Spanish National Commission for Astronomy. Based on
  observations collected at the European Southern Observatory, Chile
  (ESO No. 66.D-0031).

Title: The extraordinarily bright optical afterglow of GRB 991208
    and its host galaxy
Authors: Castro-Tirado, A. J.; Sokolov, V. V.; Gorosabel, J.;
   Castro Cerón, J. M.; Greiner, J.; Wijers, R. A. M. J.; Jensen,
   B. L.; Hjorth, J.; Toft, S.; Pedersen, H.; Palazzi, E.; Pian, E.;
   Masetti, N.; Sagar, R.; Mohan, V.; Pandey, A. K.; Pandey, S. B.;
   Dodonov, S. N.; Fatkhullin, T. A.; Afanasiev, V. L.; Komarova, V. N.;
   Moiseev, A. V.; Hudec, R.; Simon, V.; Vreeswijk, P.; Rol, E.; Klose,
   S.; Stecklum, B.; Zapatero-Osorio, M. R.; Caon, N.; Blake, C.; Wall,
   J.; Heinlein, D.; Henden, A.; Benetti, S.; Magazzù, A.; Ghinassi,
   F.; Tommasi, L.; Bremer, M.; Kouveliotou, C.; Guziy, S.; Shlyapnikov,
   A.; Hopp, U.; Feulner, G.; Dreizler, S.; Hartmann, D.; Boehnhardt,
   H.; Paredes, J. M.; Martí, J.; Xanthopoulos, E.; Kristen, H. E.;
   Smoker, J.; Hurley, K.
Bibcode: 2001A&A...370..398C
Altcode: 2001astro.ph..2177C
  Broad-band optical observations of the extraordinarily bright optical
  afterglow of the intense gamma-ray burst GRB 991208 started ~2.1 days
  after the event and continued until 4 Apr. 2000. The flux decay constant
  of the optical afterglow in the R-band is -2.30 +/- 0.07 up to ~5 days,
  which is very likely due to the jet effect, and it is followed by a
  much steeper decay with constant -3.2 +/- 0.2, the fastest one ever
  seen in a GRB optical afterglow. A negative detection in several
  all-sky films taken simultaneously with the event, that otherwise
  would have reached naked eye brightness, implies either a previous
  additional break prior to ~2 days after the occurrence of the GRB
  (as expected from the jet effect) or a maximum, as observed in GRB
  970508. The existence of a second break might indicate a steepening in
  the electron spectrum or the superposition of two events, resembling
  GRB 000301C. Once the afterglow emission vanished, contribution of a
  bright underlying supernova was found on the basis of the late-time
  R-band measurements, but the light curve is not sufficiently well
  sampled to rule out a dust echo explanation. Our redshift determination
  of z = 0.706 indicates that GRB 991208 is at 3.7 Gpc (for Ho = 60 km
  s<SUP>-1</SUP> Mpc<SUP>-1</SUP>, OMEGAo = 1 and LAMDAo = 0), implying
  an isotropic energy release of 1.15 x 10<SUP>53</SUP> erg which may be
  relaxed by beaming by a factor &gt;10<SUP>2</SUP>. Precise astrometry
  indicates that the GRB coincides within 0.2" with the host galaxy,
  thus supporting a massive star origin. The absolute magnitude of the
  galaxy is MB = -18.2, well below the knee of the galaxy luminosity
  function and we derive a star-forming rate of (11.5 +/- 7.1) Msun
  yr<SUP>-1</SUP>, which is much larger than the present-day rate in our
  Galaxy. The quasi-simultaneous broad-band photometric spectral energy
  distribution of the afterglow was determined ~3.5 day after the burst
  (Dec. 12.0) implying a cooling frequency nuc below the optical band,
  i.e. supporting a jet model with p = -2.30 as the index of the power-law
  electron distribution.

Title: Detection of pulsations in three subdwarf B stars
Authors: Østensen, R.; Solheim, J. -E.; Heber, U.; Silvotti, R.;
   Dreizler, S.; Edelmann, H.
Bibcode: 2001A&A...368..175O
Altcode:
  We report the detection of short period oscillations in the sdB stars
  <ASTROBJ>HS 0815+4243</ASTROBJ>, <ASTROBJ>HS 2149+0847</ASTROBJ> and
  <ASTROBJ>HS 2201+2610</ASTROBJ> from time-series photometry made at the
  Nordic Optical Telescope (NOT) from a sample of 31 candidates. Hence
  these three hot subdwarfs are new members of the EC 14026 class of
  pulsating sdB stars. One short period is detected for <ASTROBJ>HS
  0815+4243</ASTROBJ> (P ~ 126 s; A ~ 7 mma) and two short periods
  are seen for <ASTROBJ>HS 2149+0847</ASTROBJ> (P ~ 142, 159 s; A ~
  11, 7 mma), whereas the single oscillation detected for <ASTROBJ>HS
  2201+2610</ASTROBJ> has a considerably longer period (P ~ 350 s; A ~
  11 mma). Our NLTE model atmosphere analysis of the time-averaged
  optical spectra indicate that <ASTROBJ>HS 0815+4243</ASTROBJ>
  has T<SUB>eff</SUB> = 33 700 K and log g=5.95, <ASTROBJ>HS
  2149+0847</ASTROBJ> has T<SUB>eff</SUB> = 35 600 K and log g = 5.9,
  and <ASTROBJ>HS 2201+2610</ASTROBJ> has T<SUB>eff</SUB> = 29 300 K and
  log g= 5.4. This places the former two at the hot end and the latter
  at the cool end of the theoretical sdBV instability strip. Based on
  observations obtained at the Nordic Optical Telescope, operated on the
  island of La Palma jointly by Denmark, Finland, Iceland, Norway, and
  Sweden, in the Spanish Observatorio del Roque de los Muchachos of the
  Instituto de Astrofisica de Canarias. Based on observations collected
  at the German-Spanish Astronomical Center, Calar Alto, operated by
  the Max-Plank-Institute für Astronomie Heidelberg jointly with the
  Spanish National Commission for Astronomy.

Title: Photometric and Spectroscopic Modelling of Non-radial
    Oscillations in the sdB Star PG1605+072
Authors: Falter, S.; Heber, U.; Dreizler, S.; Cordes, O.
Bibcode: 2001AGM....18.P101F
Altcode: 2001AGAb...18R.185F
  We present the results of photometric and spectroscopic modelling of
  nonradial oscillations in subluminous B stars. Time-resolved synthetic
  spectra for a rotating star showing multi-mode non-radial pulsation are
  calculated. We use the program package BRUCE developed by R. Townsend
  (UCL, London) to compute the structure of the rotating and pulsating
  envelope. A code to construct the rotationally distorted synthetic
  spectra from these models has been developed by us. The equilibrium grid
  is distorted by one or more pulsation modes including temperature,
  velocity and geometric perturbations. We are able to model line
  profile variations in these stars as well as the photometric changes
  in different photometric filters. To test our modelling we have chosen
  the pulsating sdB stars: PG1605+072. which shows a great variety of
  pulsation modes (&gt; 50). Furthermore it has the longest periods (main
  mode at P = 480 s) and the largest radial velocity amplitudes (up to 14
  km/s). Simultaneous photometric and spectroscopic observations of this
  object recently obtained at Calar Alto Observatory are also presented.

Title: PG 1605+072: First Application of BUSCA
Authors: Cordes, O.; Reif, K.; Dreizler, S.; Heber, U.; Schuh, S.
Bibcode: 2001AGM....18..P53C
Altcode: 2001AGAb...18R.161C
  BUSCA (``Bonn University Simultaneous CAmera'') has now reached its
  final state. The instrument is now fully equipped with four 4 k×4 k 15
  μm CCDs, one backside thinned device for the UV channel and 3 frontside
  devices for the other channels. After four successful observing runs
  at Calar Alto Observatory in 2000 and 2001 BUSCA will be a standard
  instrument at the 2.2m telescope beginning with the first semester
  2002. During the commissioning procedures we were able to demonstrate
  the good optical quality of the system as well as the colour index
  stability during non photometric conditions. We found out that BUSCA
  reaches a stability of a factor of 100 better than the brightness
  fluctuations caused by clouds. As one of the first applications of BUSCA
  we observed the rapid variable star PG1605 +072. Belonging to the class
  of pulsating sdB (EC 14026) stars PG1605+072 has a dominant period
  of 480s which we are able to measure in the four primary BUSCA bands
  (UV, blue, green-yellow, near-infrared). Our relativ photometric data
  from this first simultaneous four colour observation are of excellent
  quality although the atmospheric conditions were highly variable. We
  expect to get new hints about the origin of the pulsating mechanisms
  from analysing the colour index light curves.

Title: Stratified Non-LTE Model Atmospheres for Hot Hydrogen Rich
    White Dwarfs
Authors: Schuh, Sonja L.; Dreizler, Stefan; Wolff, Burkhard
Bibcode: 2001AGM....18S0916S
Altcode:
  We present our recent work towards stratified non-LTE model atmospheres
  and applications thereof. The chemical stratification in our stellar
  atmosphere models is determined from the equilibrium between gravity
  and radiative levitation. The chemical composition is therefore
  no longer a free parameter but is determined from the fundamental
  atmospheric parameters, effective temperature and surface gravity,
  alone. Spectroscopic EUV data of hot DA white dwarfs are used as
  an observational basis to test the predictions of these chemically
  stratified, self-consistently constructed models. New values for the
  fundamental parameters are being derived for the sample stars and
  successfully interpreted within the framework of diffusion theory. For
  the first time, equilibrium abundance calculations are found to be in
  good agreement with observations for a large sample.

Title: AcDc - A new Code to Calculate the Vertical Structure of
    Accretion Disks
Authors: Nagel, T.; Werner, K.; Dreizler, S.
Bibcode: 2001AGM....18..P47N
Altcode:
  We present a new code to calculate the vertical structure of accretion
  disks in cataclysmic variables. The disk is divided into concentric
  rings, each ring is treated like an independent plane-parallel
  radiating slab. We first calculate a gray LTE model and then a NLTE
  model of the ring. Finally we integrate over all ring spectra to get
  the spectrum of the full disk. The system of hydrostatic and radiative
  equilibrium, atomic level populations and particle conservation
  is solved consistently with the radiative transfer. This allows to
  calculate detailed theoretical spectra of accretion disks. Comparison
  with observations will allow to derive radial temperature distribution,
  mass accretion rate, viscosity and chemical composition. We also plan
  to compare our vertical structures to those of hydrodynamic simulations
  in order to estimate the influence of a detailed radiation transport
  on the stratification.

Title: High resolution Keck and NTT spectra of PG 1159 stars
Authors: Köper, S.; Rauch, T.; Dreizler, S.; Heber, U.; Reid, I. N.;
   Werner, K.
Bibcode: 2001ASPC..226...65K
Altcode: 2001ewwd.work...65K
  No abstract at ADS

Title: FUSE observations of the PG 1159-type Central Star K 1-16
Authors: Miksa, S.; Deetjen, J. L.; Dreizler, S.; Herwig, F.; Kruk,
   J. W.; Rauch, T.; Werner, K.
Bibcode: 2001ASPC..226...60M
Altcode: 2001ewwd.work...60M
  No abstract at ADS

Title: Sphericity Effects in Metal-Line Blanketed NLTE Model
    Atmospheres
Authors: Nagel, T.; Dreizler, S.; Werner, K.
Bibcode: 2001ASPC..226...86N
Altcode: 2001ewwd.work...86N
  No abstract at ADS

Title: Rotation Velocities of White Dwarfs
Authors: Karl, C.; Napiwotzki, R.; Heber, U.; Dreizler, S.; Koester,
   D.; Reid, I. N.
Bibcode: 2001AGM....18S0918K
Altcode: 2001AGAb...18...98K
  White dwarfs are the compact remnants of low and intermediate
  mass stars (M &lt; 8M<SUB>solar</SUB>). Due to the conservation of
  angular momentum white dwarfs should be very fast rotators, if a
  significant fraction of the angular momentum of the progenitor stars
  were preserved. The existence of sharp NLTE cores of the hydrogen Hα
  line in high resolution spectra (obtained at the Keck observatory)
  of DA white dwarfs allowed us to determine (projected) rotational
  velocities v sin i for white dwarfs. Among those of our targets
  lying close to the ZZ Ceti instability many show evidence for extra
  broadening similar to rotation, whereas stars at higher temperatures
  (and therefore younger ones) rotate more slowly or not at all. Our
  result based on a large sample is in accordance with previous results
  presented by Koester et al. (1998). We discuss possible explanations
  for this astonishing result.

Title: Polarized Thermal Radiation from Neutron Star Atmospheres
Authors: Deetjen, Jochen L.; Dreizler, Stefan; Werner, Klaus
Bibcode: 2001AGM....18.P121D
Altcode:
  We present model atmospheres appropriate for the spectroscopic analysis
  of the thermal spectra of old isolated neutron stars. The models
  consider the correct opacities from hydrogen exposed to magnetic fields
  in the range of 10<SUP>7</SUP> Gauss from Ruder et al. (1994). For the
  first time, these models account for deviations from LTE as well. Our
  synthetic spectra are calculated in two successive steps. At first a
  model atmosphere is calculated by the simultaneous solution of many
  thousands of radiation transfer equations under the constraints
  of hydrostatic and radiative equilibrium as well as statistical
  equilibrium for atomic level populations. The solution method is an
  Accelerated Lambda Iteration (ALI) technique (Werner &amp; Dreizler,
  1999). Thereby we neglect the magnetic field. In the second step the
  atmospheric structure is kept fix and and a synthetic spectrum is
  calculated by solving the full polarized radiation transfer equation
  (PRT). We are using the Stokes vector to describe the radiation
  field and apply the PRT version of Accelerated Lambda Iteration (ALI)
  technique (Takeda, 1991). References: Ruder H., Wunner G., Herold H.,
  Geyer F., 1994, Atoms in Strong Magnetic Fields, A&amp;A Library,
  1st edition Takeda Y, 1991, PASJ 43, 719 Werner K., Dreizler S., 1999,
  Journal of Computational and Applied Math. 109, 65

Title: New Pulsating sdB Stars from the HS Survey
Authors: Silvotti, R.; Solheim, J. -E.; Heber, U.; Østensen, R.;
   Dreizler, S.; Edelmann, H.
Bibcode: 2001ASPC..226..177S
Altcode: 2001ewwd.work..177S
  No abstract at ADS

Title: Application of Stratified Non-LTE Model Atmospheres to Hot
    DA White Dwarfs
Authors: Schuh, S.; Dreizler, S.; Wolff, B.
Bibcode: 2001ASPC..226...79S
Altcode: 2001ewwd.work...79S
  No abstract at ADS

Title: Stratified Non-LTE Model Atmospheres for hot White Dwarfs
Authors: Dreizler, S.; Schuh, S.
Bibcode: 2001ASPC..226...69D
Altcode: 2001ewwd.work...69D
  No abstract at ADS

Title: sdO Stars
Authors: Dreizler, S.
Bibcode: 2000eaa..bookE5412D
Altcode:
  Subdwarfs of spectral type O (sdO stars) are hot evolved stars with a
  lower luminosity than main sequence O stars. The sdO stars cover a wide
  range in the HERTZSPRUNG-RUSSELL DIAGRAM (HRD, see figure 1). At lower
  luminosities and temperatures they form the extension of the subdwarfs
  of spectral type B (sdB), bounded by the extreme blue extension of
  the Horizontal Branch (EHB) and the helium mai...

Title: PG 1618+563B: A new bright pulsating sdB star
Authors: Silvotti, R.; Solheim, J. -E.; Gonzalez Perez, J. M.; Heber,
   U.; Dreizler, S.; Edelmann, H.; Østensen, R.; Kotak, R.
Bibcode: 2000A&A...359.1068S
Altcode:
  The results of two runs of time-series photometry made at the Nordic
  Optical Telescope clearly show that the sdB star PG 1618+563B is a
  new member of the EC 14026 class of sdB pulsators. Its power spectrum
  shows a doublet of frequencies at about 6.95 and 7.18 mHz (P ~ 144 and
  139 s respectively), which produce a modulation effect in the light
  curve with a beat period of about 1.2 hours. The amplitudes of the two
  signals are very low, not more than 2 mma. Thanks to its brightness
  (B=13.4), which makes PG 1618+563B one of the brightest objects of its
  class, we were able to observe the star also in different colours and
  measure its UBV pulsation amplitudes and phases. The comparison of these
  ``nonadiabatic observables'' with models may help the identification
  of the oscillation modes. The spectral analysis of the sdB star and the
  spectral classification of PG 1618+563A suggest that both stars form a
  wide visual binary ( ~ 2500 A.U. separation), at a distance of about 680
  pc from the sun. Based on observations obtained at the Nordic Optical
  Telescope, operated on the island of La Palma jointly by Denmark,
  Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del
  Roque de los Muchachos of the Instituto de Astrofisica de Canarias. And
  on observations obtained at the German-Spanish Astronomical Center,
  Calar Alto, operated by the Max-Planck-Institut für Astronomie
  Heidelberg jointly with the Spanish National Commission for Astronomy

Title: NLTE Model Atmospheres for Extremely Hot Compact Stars
Authors: Rauch, T.; Deetjen, J. L.; Dreizler, S.; Werner, K.
Bibcode: 2000IAUS..195..423R
Altcode:
  Present observational techniques provide stellar spectra with
  high resolution at a high signal-to-noise ratio over the complete
  wavelength range---from the far infrared to X-rays. The effects of
  Non-``Local Thermal Equilibrium'' (NLTE) are particularly important
  for hot stars, hence the use of reliable NLTE stellar model atmosphere
  fluxes is required for an adequate spectral analysis. State-of-the-art
  NLTE model atmospheres include metal-line blanketing of millions of
  lines of all elements from hydrogen up to the iron-group elements,
  and thus permit precise analyses of extremely hot compact stars, e.g.,
  central stars of planetary nebulae, PG 1159 stars, white dwarfs, and
  neutron stars. Their careful spectroscopic study is of great interest
  in several branches of modern astrophysics, e.g., stellar and galactic
  evolution, and interstellar matter.

Title: The discovery of photospheric nickel in the hot DO white
    dwarf REJ 0503-289
Authors: Barstow, M. A.; Dreizler, S.; Holberg, J. B.; Finley, D. S.;
   Werner, K.; Hubeny, I.; Sion, E. M.
Bibcode: 2000MNRAS.314..109B
Altcode:
  We present the first evidence for the direct detection of nickel
  in the photosphere of the hot DO white dwarf REJ 0503-289. While
  this element has been seen previously in the atmospheres of hot
  H-rich white dwarfs, this is one of the first similar discoveries
  in a He-rich object. Intriguingly, iron, which is observed to
  be more abundant than Ni in the hot DA stars, is not detected,
  the upper limit to its abundance (Fe/He=10<SUP>-6</SUP>) implying
  an Fe/Ni ratio a factor of 10 lower than seen in the H-rich objects
  (Ni/He=10<SUP>-5</SUP> for REJ 0503-289). The abundances of nickel and
  various other elements heavier than He were determined from Goddard High
  Resolution Spectrograph spectra. We used two completely independent
  sets of non-local thermodynamic equilibrium model atmospheres, which
  both provide the same results. This not only reduces the possibility of
  systematic errors in our analysis, but is also an important consistency
  check for both model atmosphere codes. We have also developed a more
  objective method of determining T<SUB>eff</SUB> and logg, from the He
  lines in the optical spectrum, in the form of a formal fitting of the
  line profiles to a grid of model spectra, an analogue of the standard
  procedure utilizing the Balmer lines in DA white dwarfs. This gives the
  assigned uncertainties in T<SUB>eff</SUB> and logg a firm statistical
  basis and allows us to demonstrate that inclusion of elements heavier
  than H, He and C in the spectral calculations, exclusively considered
  in most published optical analyses, yields a systematic downward shift
  in the measured value of T<SUB>eff</SUB>.

Title: NLTE Model Atmospheres for Central Stars of Planetary Nebulae
Authors: Rauch, Thomas; Deetjen, Jochen L.; Dreizler, Stefan;
   Werner, Klaus
Bibcode: 2000ASPC..199..337R
Altcode: 2000apn..conf..337R; 1999astro.ph..9507R
  Present observational techniques provide stellar spectra with
  high resolution at a high signal-to-noise ratio over the complete
  wavelength range - from the far infrared to the X-ray. NLTE effects are
  particularly important for hot stars, hence the use of reliable NLTE
  stellar model atmosphere fluxes is required for an adequate spectral
  analysis. State-of-the-art NLTE model atmospheres include the metal-line
  blanketing of millions of lines of all elements from hydrogen up to
  the iron-group elements and thus permit precise analyses of extremely
  hot compact stars, e.g. central stars of planetary nebulae, PG 1159
  stars, white dwarfs, and neutron stars. Their careful spectroscopic
  study is of great interest in several branches of modern astrophysics,
  e.g. stellar and galactic evolution, and interstellar matter.

Title: CCD Photometry of Variable Subdwarfs and White Dwarfs at
    Calar Alto Observatory
Authors: Schuh, Sonja; Dreizler, Stefan; Deetjen, Jochen L.; Heber,
   Uli; Geckeler, Ralf D.
Bibcode: 2000BaltA...9..395S
Altcode: 2000OAst....9..395S
  We report on our time-resolved photometry of subdwarfs and white
  dwarfs at the Calar Alto Observatory. Candidates are taken from a
  spectroscopically pre-selected sample obtained from the Hamburg Schmidt
  Survey. We also report on our experience during the WET run in April
  1999 and introduce our revised CCD photometry reduction package TRIPP,
  as well as preliminary results.

Title: PG 1618+563: A New Bright Pulsating sdB Star
Authors: Silvotti, R.; Gonzalez Perez, J. M.; Solheim, J. -E.; Heber,
   U.; Dreizler, S.; Edelmann, H.
Bibcode: 2000BaltA...9..205S
Altcode: 2000OAst....9..205S
  Recent observations at the NOT telescope clearly show that PG 1618+563
  is a new member of the EC14026 class of sdB pulsating stars (Kilkenny
  et al. 1997, O'Donoghue et al. 1999). The very good quality of the
  non-filtered data allows to detect an amplitude modulation effect
  with a beat period of about 1.2 hours, which is consistent with the
  presence in the temporal spectrum of two close frequencies at 6.95
  and 7.14 mHz ( ~ 144 and 140 s). The amplitudes are very low: between
  1 and 2 mma. Moreover, from UBV data we find amplitude (and phase)
  differences, that could be useful for mode identification.

Title: Preliminary Results from XCOV 17: PG 1336-018
Authors: Reed, M. D.; Kilkenny, D.; Kawaler, S. D.; Mukadam, A.;
   Kleinman, S. J.; Nitta-Kleinman, A.; Provencal, J. L.; Watson, T.;
   Sullivan, D.; Sullivan, T.; Shobbrook, B.; Jiang, X. J.; Ashoka, B. N.;
   Seetha, S.; Leibowitz, E.; Ibbetson, P.; Mendelson, H.; Meistas, E. G.;
   Kalytis, R.; Alisauskas, D.; O'Donoghue, D.; Martinez, P.; van Wyk,
   F.; Stobie, R.; Marang, F.; Zola, S.; Krzesinski, J.; Ogloza, W.;
   Moskalik, P.; Silvotti, R.; Piccioni, A.; Vauclair, G.; Dolez, N.;
   Rene-Fremy, J.; Chevreton, M.; Ulla, A.; Dreizler, S.; Schuh, S.;
   Deetjen, J.; Solheim, J. E.; Perez, J.; Suarez, O.; Manteiga, M.;
   Burleigh, M.; Barstow, M.; Kepler, S. O.; Kanaan, A.; Giovannini,
   O.; Metcalfe, T.; Ostensen, R.
Bibcode: 2000BaltA...9..183R
Altcode: 2000OAst....9..183R
  We present a preliminary analysis of the data collected during the
  1999/1 (XCOV17) Whole Earth Telescope (WET) campaign to observe the
  pulsating subdwarf B star PG 1336-018. Since PG 1336-018 is an HW Vir
  type eclipsing binary, our hope is to use the known orbital period,
  assume a tidally locked system, and search for rotationally split
  modes. To this end, we can already report some success.

Title: The Amplitude Differences Between CCD and PMT Measurements
Authors: Kanaan, A.; O'Donoghue, D.; Kleinman, S. J.; Krzesinski,
   J.; Koester, D.; Dreizler, S.
Bibcode: 2000BaltA...9..387K
Altcode: 2000OAst....9..387K
  Using model atmospheres, quantum efficiency and transmission curves,
  we compute expected values for amplitudes of DAV, DBV and DOV
  stellar models as measured through different detectors and/or filter
  combinations. We conclude that choosing the wrong detector may lead to
  amplitudes lower by 20 % than those measured by phototubes. The correct
  choice of CCD + filter may reduce this problem down to a difference
  of 6 %.

Title: Trace elements and radiative levitation in hot helium-rich
    white dwarfs
Authors: Dreizler, Stefan
Bibcode: 2000fuse.prop.A013D
Altcode:
  We propose to observe three helium-rich (DO) white dwarfs in order to
  determine their photospheric abundances of trace elements (e.g. C, N, O,
  H, Fe, Ni,...). FUSE spectroscopy is ideal for this purpose since the
  FUV allows to explore a large variety of line transitions of various
  elements which are not detectable in existing optical or UV spectra
  of the targets. The data will be analyzed with non-LTE metal line
  blanketed model atmospheres. The results will be compared to predictions
  from newly developed, self-consistent diffusion/radiative levitation
  calculations under non-LTE conditions. The observed metal abundances
  will serve as bench-marks for such kind of new calculations. <P />As a
  basis for this work we have obtained high-S/N optical spectra of almost
  all known DO white dwarfs within the last five years as well as HST
  GHRS spectra of selected DO white dwarfs. A comprehensive analysis of
  the atmospheric parameters is now available. For the present proposal
  we have selected three targets which -- together with calibration and
  PI targets-- represent the non-DA white dwarf cooling sequence from
  the hot end down to the DB gap.

Title: Time-Resolved Spectroscopy of BPM 37093 and PG 1336-018
Authors: Dreizler, Stefan; Koester, Detlev; Heber, Uli
Bibcode: 2000BaltA...9..113D
Altcode: 2000OAst....9..113D
  We present time-resolved spectroscopy of two pulsating stars using VLT
  UT1. Primary aim is an identification of the pulsation modes from the
  wavelength dependency of the amplitudes. A mode identification is the
  prerequisite to make full use of the photometric data obtained for
  asteroseismologic studies.

Title: Hubble Space Telescope spectroscopy of hot helium-rich white
dwarfs: metal abundances along the cooling sequence
Authors: Dreizler, S.
Bibcode: 1999A&A...352..632D
Altcode:
  Metal abundances are the indicators of the chemical evolution in white
  dwarfs, which is dominated by the element separation due to the strong
  gravitational field. A reliable analysis and interpretation requires
  high resolution and high signal-to-noise UV spectroscopy. For hot
  helium rich DO white dwarfs this is currently only feasible with the
  Hubble Space Telescope. In this paper I report on our HST spectroscopy
  of DO white dwarfs and describe our model atmospheres employed for the
  analysis. This includes an introduction to our new self-consistent,
  chemically stratified non-LTE model atmospheres, which take into
  account gravitational sedimentation and radiative levitation. The
  results of the analysis shows that DO white dwarfs can best be fitted
  with chemically homogeneous models, whereas stratified models show
  significant deviations. Several possible reasons for this unexpected
  result are discussed. At the current stage, weak mass loss is the
  most plausible explanation. Based on observations obtained with the
  NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science
  Institute, which is operated by the Association of Universities for
  Research in Astronomy, Inc., under NASA contract NAS 5-26555

Title: HST/STIS ultraviolet spectroscopy of the supersoft X-ray
    source RX J0439.8-6809
Authors: van Teeseling, A.; Gänsicke, B. T.; Beuermann, K.; Dreizler,
   S.; Rauch, T.; Reinsch, K.
Bibcode: 1999A&A...351L..27V
Altcode: 1999astro.ph.10330V
  We present ultraviolet observations of the supersoft X-ray source
  RX J0439.8-6809 obtained with the Hubble Space Telescope Imaging
  Spectrograph. The ultraviolet spectrum is a very blue continuum
  overlayed with interstellar absorption lines. The observed broad Lyalpha
  absorption line is consistent with an interstellar column density of
  neutral hydrogen N_HI=(4.0+/-1.0)*E<SUP>20};cm<SUP>{-2</SUP></SUP>. The
  light curve obtained from the time-tagged dataset puts a 3sigma upper
  limit of 0.04 mag on the ultraviolet variability of RX J0439.8-6809 on
  time scales between 10 s and 35 min. The long-term X-ray light curve
  obtained from our three-year ROSAT HRI monitoring of RX J0439.8-6809
  shows the source with a constant count rate, and implies that the
  temperature did not change more than a few 1000 K. If RX J0439.8-6809 is
  a massive extremely hot pre-white dwarf on the horizontal shell-burning
  track, opposed to the alternative possibility of a very compact
  double-degenerate supersoft X-ray binary, its constant temperature and
  luminosity are a challenge to stellar evolution theory. Interestingly,
  RX J0439-6809 is found close to the theoretical carbon-burning
  main-sequence. Based on observations made with the NASA/ESA Hubble
  Space Telescope, obtained at the Space Telescope Science Institute,
  which is operated by the Association of Universities for Research in
  Astronomy, Inc., under NASA contract NAS 5-26555.

Title: The classical stellar atmosphere problem.
Authors: Werner, K.; Dreizler, S.
Bibcode: 1999JCoAM.109...65W
Altcode: 1999astro.ph..6130W
  The authors introduce the classical stellar atmosphere problem and
  describe in detail its numerical solution. The problem consists of the
  solution of the radiation transfer equations under the constraints of
  hydrostatic, radiative and statistical equilibrium (non-LTE). They
  outline the basic idea of the accelerated lambda iteration (ALI)
  technique and statistical methods which finally allow the construction
  of non-LTE model atmospheres considering the influence of millions
  of metal absorption lines. Some applications of the new models are
  presented.

Title: Analysis of ultraviolet and extreme-ultraviolet spectra of
    the DA white dwarf G 191-B2B using self-consistent diffusion models
Authors: Dreizler, S.; Wolff, B.
Bibcode: 1999A&A...348..189D
Altcode:
  We present a multi-wavelength spectral analysis of the DA white dwarf
  G 191-B2B. The employed atmospheric models account for gravitational
  settling and radiative levitation, which are, for the first time,
  calculated self-consistently with the atmospheric structure. The
  resulting spectra can reproduce the complete EUVE spectrum and
  the ultraviolet lines of iron. Some restrictions regarding the UV
  lines of other elements (C, N, O, Ni), however, still remain. In
  contrast to homogeneous models, it is not necessary to introduce
  additional photospheric or interstellar absorbers to account for
  the high opacity at lambda &lt;~ 230 Ä. Abundance profile changing
  mechanisms, like mass-loss or accretion, are also not needed. Based on
  observations made with the EUVE Sattelite and with the NASA/ESA Hubble
  Space Telescope, obtained from the data archive at the Space Telescope
  Science Institute. STScI is operated by the Association of Universities
  for Research in Astronomy, Inc. under NASA contract NAS 5-26555.

Title: The iron abundance in hot central stars of planetary nebulae
    derived from IUE spectra
Authors: Deetjen, J. L.; Dreizler, S.; Rauch, T.; Werner, K.
Bibcode: 1999A&A...348..940D
Altcode: 2000astro.ph..6338D
  We present the first attempt to determine the iron abundance in
  hot central stars of planetary nebulae. We perform an analysis with
  fully metal-line blanketed NLTE model atmospheres for a sample of ten
  stars (T_eff &gt;~ 70 000 K) for which high-resolution UV spectra
  are available from the IUE archive. In all cases lines of Fe Vi or
  Fe Vii can be identified. As a general trend, the iron abundance
  appears to be subsolar by 0.5-1 dex, however, the S/N of the IUE
  spectra is not sufficient to exclude a solar abundance in any specific
  case. Improved spectroscopy by either FUSE or HST is necessary to verify
  the possibility of a general iron deficiency in central stars. The
  suspected deficiency may be the result of gravitational settling in
  the case of three high-gravity objects. For the other stars with low
  gravity and high luminosity dust fractionation during the previous
  AGB phase is a conceivable origin. Based on observations with the
  International Ultraviolet Explorer (IUE) satellite.

Title: The photometric behaviour of the peculiar PG 1159 star HS
    2324+3944 at high frequency resolution
Authors: Silvotti, R.; Dreizler, S.; Handler, G.; Jiang, X. J.
Bibcode: 1999A&A...342..745S
Altcode: 1998astro.ph.11178S
  We present the results from 135 hours of nearly continuous time
  series photometry on the ``hybrid'' (H-rich) PG 1159 variable star HS
  2324+3944, obtained in August-September 1997. The power spectrum of
  the data shows several frequencies (about 20 or more), concentrated
  in three narrow and very crowded regions near 475, 390 and 950 mu Hz
  in decreasing amplitude order. Most (if not all) of the peaks in the
  latter region are linear combinations of the high-amplitude frequencies
  between 455 and 500 mu Hz. If we divide the data set into two equal
  parts, the power spectra are different. This is probably due to a not
  sufficiently long (and therefore not completely resolved) light curve;
  nevertheless an alternative hypothesis of a single damped oscillator
  may not be completely ruled out. If we adopt the first hypothesis,
  the high concentration of peaks between 455 and 500 mu Hz suggests
  the presence of both l=1 and l=2 high-overtone nonradial g-modes. The
  insufficient frequency resolution of our data does not allow to obtain
  definite precision asteroseismology results. Nevertheless a spacing
  of the signals is observed, probably due to stellar rotation with a
  period of 2.3 days. If the signal spacing was due to the successive
  overtones, the period spacings would be equal to 18.8 (l=1) and 10.4
  (l=2) s. Based on observations obtained at the McDonald, Loiano and
  Beijing Observatories and at the German-Spanish Astronomical Center,
  Calar Alto, operated by the Max-Planck-Institut für Astronomie
  Heidelberg jointly with the Spanish National Commission for Astronomy.

Title: Iron abundance in hot central stars of planetary nebulae
Authors: Deetjen, J. L.; Dreizler, S.; Rauch, T.; Werner, K.
Bibcode: 1999AGAb...15..119D
Altcode: 1999AGM....15..P64D
  We present the first attempt to determine the iron abundance in
  hot central stars of planetary nebulae. We perform an analysis with
  fully metal-line blanketed NLTE model atmospheres for a sample of ten
  stars (T_eff &gt;~ 70 000 K) for which high-resolution UV spectra
  are available from the IUE archive. In all cases lines of Fe vi or
  Fe vii can be identified. As a general trend, the iron abundance
  appears to be subsolar by 0.5-1 dex, however, the S/N of the IUE
  spectra is not sufficient to exclude a solar abundance in any specific
  case. Improved spectroscopy by either FUSE or HST is necessary to verify
  the possibility of a general iron deficiency in central stars. The
  suspected deficiency may be the result of gravitational settling in
  the case of three high-gravity objects. For the other stars with low
  gravity and high luminosity dust fractionation during the previous
  AGB phase is a conceivable origin.

Title: HST spectroscopy of hot hydrogen deficient white dwarfs
Authors: Dreizler, S.
Bibcode: 1999ASPC..169..499D
Altcode: 1999ewwd.conf..499D
  No abstract at ADS

Title: Iron and nickel abundances in hot hydrogen-rich central stars
    of planetary nebulae
Authors: Deetjen, J. L.; Dreizler, S.; Rauch, T.; Werner, K.
Bibcode: 1999ASPC..169..475D
Altcode: 1999ewwd.conf..475D
  No abstract at ADS

Title: Born-again AGB stars: Starting point of the H-deficient
    post-AGB evolutionary sequence?
Authors: Werner, K.; Dreizler, S.; Rauch, T.; Koesterke, L.; Heber, U.
Bibcode: 1999IAUS..191..493W
Altcode:
  We discuss the origin of hot hydrogen-deficient post-AGB stars. Evidence
  is growing that the ``born-again AGB star scenario'' as a consequence of
  a late He shell flash cannot explain the diverse observations. Analyses
  of the stars and their associated planetary nebulae suggest that
  the H-deficiency is not formed during the second post-AGB phase but
  already while the star is still on the AGB. There are even hints that
  the H-deficiency can occur before the first departure from the AGB.

Title: Sphericity effects in non-LTE model atmospheres for hot stars
Authors: Nagel, T.; Dreizler, S.; Werner, K.
Bibcode: 1999AGAb...15..104N
Altcode: 1999AGM....15..P35N
  Spectral analyses of hot compact stars (white dwarfs, sdO stars,
  central stars of planetary nebulae) are usually performed with model
  atmospheres assuming plane-parallel geometry. This approximation
  becomes questionable in case of observational data with very high
  signal-to-noise where even tiny effects become visible or, because of
  their extended atmospheres, for objects close to the Eddington limit. As
  long as wind effects are negligible, static and spherically symmetric
  models can be used. We describe how our non-LTE model atmosphere code
  has been generalized to spherical geometry and present results from
  our first model calculations. This new implementation is used to study
  sphericity effects on atmospheric structure and line profiles which
  are compared to effects arising from non-LTE metal line blanketing.

Title: EUVE observations of DA white dwarfs
Authors: Wolff, B.; Koester, D.; Dreizler, S.
Bibcode: 1999ASPC..169..524W
Altcode: 1999ewwd.conf..524W
  No abstract at ADS

Title: NLTE Model Atmospheres for Extremely Hot Compact Stars
Authors: Rauch, Thomas; Deetjen, Jochen L.; Dreizler, Stefan;
   Werner, Klaus
Bibcode: 1999AGAb...15..105R
Altcode: 1999AGM....15..P36R
  Present observational techniques provide stellar spectra with
  high resolution at a high signal-to-noise ratio over the complete
  wavelength range - from the far infrared to the X-ray. NLTE effects are
  particularly important for hot stars, hence the use of relia ble NLTE
  stellar model atmosphere fluxes is required for an adequate spectral
  analysis. State-of-the-art NLTE model atmospheres include the metal-line
  blanketing of millions of lines of all elements from hydrogen up to
  the iron-group elements and thus permit precise analyses of extremely
  hot compact stars, e.g. central stars of planetary nebulae, PG 1159
  stars, white dwarfs, and neutron stars. Their careful spectroscopic
  study is of great interest in several branches of modern astrophysics,
  e.g. stellar and galactic evolution, and interstellar mat ter.

Title: Spectroscopy of Hot Hydrogen Deficient White Dwarfs
Authors: Dreizler, Stefan
Bibcode: 1999RvMA...12..255D
Altcode:
  No abstract at ADS

Title: Equilibrium Abundances in Hot White Dwarfs
Authors: Schuh, Sonja; Dreizler, Stefan; Wolff, Burkhard
Bibcode: 1999AGAb...15..105S
Altcode:
  Metal abundances are the indicators of the chemical evolution in
  white dwarfs, which is dominated by the sedimentation of the heavier
  elements due to the strong gravitational field. A reliable analysis
  and interpretation requires high resolution and high signal-to-noise
  UV and EUV spectroscopy. It can only be performed in these wavelength
  ranges as the weak metal lines needed for the analysis do not show up
  in the optical regime. During previous work by Wolff et al. (A&amp;A
  329, 1045), the spectra of hot, hydrogen rich white dwarfs as detected
  by EUVE were analysed and effective temperatures, surface gravity
  and metallicities were determined using chemically homogeneous
  model atmospheres. We now present calculations of self-consistent,
  chemically stratified non-LTE model atmospheres which take into
  account gravitational sedimentation and radiative levitation. In the
  case of G191-B2B, these new, refined models are able to reproduce the
  EUVE observations to an unprecedented degree of accuracy (Dreizler et
  al., A&amp;A 348, 189). This result is now to be checked for a larger
  sample of objects using UV spectra from IUE and HST as well as future
  FUSE spectra.

Title: The stellar content of the Hamburg Quasar Survey
Authors: Homeier, D.; Koester, D.; Jordan, S.; Hagen, H. -J.; Engels,
   S.; Heber, U.; Dreizler, S.
Bibcode: 1999ASPC..169...37H
Altcode: 1999ewwd.conf...37H
  No abstract at ADS

Title: Results of the multi-site photometric campaign on HS 2324+3944
Authors: Silvotti, R.; Dreizler, S.; Handler, G.; Jiang, X.
Bibcode: 1999ASPC..169..100S
Altcode: 1999ewwd.conf..100S
  No abstract at ADS

Title: Observations of Variable [pre-] White Dwarfs
Authors: Dreizler, S.; Schuh, S.; Deetjen, J.; Heber, U.; Edelmann,
   H.; Koester, D.
Bibcode: 1999AGAb...15..106D
Altcode:
  Stellar seismology is an extremely valuable tool for a direct
  investigation of stellar structure and evolution. The usual
  observational approach is photometric monitoring of stars, yielding
  pulsation frequencies and amplitudes. The comparison of the observed
  modes with predicted ones are then used to probe the stellar
  structure. The typical separation of consecutive overtones in these
  stars are of the same order as the side bands in the Fourier spectrum
  produced by the periodic day interruption. Thus, in order to obtain
  light curves suitable for a detailed seismologic analysis, world wide
  coordinated observing campaigns are required (Whole Earth Telescope,
  WET). Using the Calar Alto 1.23m telescope, we participated in the
  last WET campaign, where the close binary PG 1336-018, a pulsating
  sdB and a very cool main sequence star, was observed. Using the same
  instrumentation, we also searched for new candidates of variable
  [pre-] white dwarfs. A seismologic analysis requires a reliable mode
  identification, namely the degree l denoting the number of node lines of
  the non-radial pulsation. In the case of many observed eigenmodes these
  can be identified by a comparison with theoretical predictions. When
  only very few modes are present this comparison is ambiguous and an
  alternative approach is required, i.e. an evaluation of wavelength
  dependent pulsation amplitudes as seen in time-resolved spectroscopy
  of two variable [pre-] white dwarfs performed with the VLT.

Title: Search for rotation in white dwarfs
Authors: Koester, D.; Dreizler, S.; Weidemann, V.; Allard, N. F.
Bibcode: 1999ASPC..169..415K
Altcode: 1999ewwd.conf..415K
  No abstract at ADS

Title: FUV spectroscopy of DO and PG 1159 stars with ORFEUS
Authors: Werner, K.; Dreizler, S.; Rauch, T.; Barnstedt, J.; Gölz,
   M.; Gringel, W.; Kappelmann, N.; Krämer, G.; Widmann, H.; Koesterke,
   L.; Haas, S.; Heber, U.; Appenzeller, I.; Grewing, M.
Bibcode: 1999ASPC..169..511W
Altcode: 1999ewwd.conf..511W
  No abstract at ADS

Title: An analysis of DA white dwarfs from the Hamburg Quasar Survey
Authors: Homeier, D.; Koester, D.; Hagen, H. -J.; Jordan, S.; Heber,
   U.; Engels, D.; Reimers, D.; Dreizler, S.
Bibcode: 1998A&A...338..563H
Altcode:
  Follow-up spectroscopy of several hundred hot stars detected by
  the Hamburg Quasar Survey (HQS) has been carried out between 1989
  and 1996. We present the analysis of 80 DA white dwarfs using model
  atmospheres and theoretical cooling tracks to derive the atmospheric
  parameters T_eff and log g, masses and absolute magnitudes. The HQS
  turned out to be sensitive to the detection of hydrogen-rich white
  dwarfs in a wide temperature range, from 10 000 K upwards. Star counts
  within four HQS fields for magnitudes B&lt;= 16fm 4 exceed those from
  the Palomar Green survey by about 50%. The more recent observation
  campaigns emphasized the detection of very hot degenerates, yielding
  a large fraction of DA stars with T_eff &gt; 50 000 K compared to
  other surveys. The mean mass of our DA sample is M=0.61{M}_{\odot},
  with three massive DA stars exceeding 1{M}_{\odot} and three DA
  stars with masses significantly below the assummed lower mass limit
  for single white dwarf evolution of 0.45{M}_{\odot}. Among the cool
  DA stars, thirteen are potential ZZ Ceti candidates because their
  effective temperatures lie close to the instability strip. Based
  on observations collected at the German-Spanish Astronomical Center
  (DSAZ), Calar Alto, operated by the Max-Plank-Institut für Astronomie
  Heidelberg jointly with the Spanish National Commission for Astronomy;
  with the International Ultraviolet Explorer satellite (IUE) collected
  at Villafranca, Spain, and with the ROSAT X-ray telescope.

Title: Search for rotation in white dwarfs
Authors: Koester, D.; Dreizler, S.; Weidemann, V.; Allard, N. F.
Bibcode: 1998A&A...338..612K
Altcode:
  We report high-resolution spectroscopic observations of the
  NLTE Hα core in 28 DA white dwarfs. From a comparison with
  theoretically broadened NLTE models projected rotation velocities can
  be determined. The majority of objects are found to be compatible with
  zero or very small rotation with typical upper limits for v sin i of 15
  km/s, corresponding to periods of hours or longer. The implications for
  the loss of angular momentum during the evolution of the progenitors
  is discussed. Three new magnetic white dwarfs are detected with very
  small tangential fields in the range of 30 to 50 kG. In two more
  magnetic objects known before we found field strengths significantly
  larger than the mean longitudinal fields determined from the circular
  polarization. Very puzzling is the result for three ZZ Ceti stars in the
  sample, which all seem to have projected rotational velocities between
  30 and 45 km/s, in conflict with asteroseismological results. Based on
  observations collected at the European Southern Observatory, La Silla,
  Chile (55.D-0459, 57.D-0631)

Title: Spectral analysis of O(He)-type post-AGB stars
Authors: Rauch, T.; Dreizler, S.; Wolff, B.
Bibcode: 1998A&A...338..651R
Altcode:
  We present an analysis of two recently discovered, very hot
  hydrogen-deficient post-AGB stars of spectral type O(He), namely HS
  1522+6615 and HS 2209+8229, by means of state-of-the-art NLTE model
  atmospheres based on new optical, UV, and X-ray observations. In
  the spectra of HS 1522+6615 we discovered a variability of the
  \Ionw{O}{6}{5290} line complex on a time scale of few days. We also
  report on the discovery of a ring structure in the planetary nebula K
  1-27 which has an O(He)-type central star. We discuss how the group
  of O(He) stars fits in our picture of hydrogen-deficient post-AGB
  stellar evolution. Based on observations obtained at the German-Spanish
  Astronomical Center, Calar Alto, operated by the Max-Planck-Institut
  für Astronomie Heidelberg jointly with the Spanish National Commission
  for Astronomy; collected at the European Southern Observatory, La Silla,
  Chile; on observations made with ROSAT, retrieved from the archive;
  and on observations made with the International Ultraviolet Explorer
  (IUE) and retrieved from the IUE Final Archive; this research has made
  use of the SIMBAD database, operated at CDS, Strasbourg, France

Title: Spectral analyses of PG 1159 star: constraints on the GW
    Virginis pulsations from HST observations
Authors: Dreizler, S.; Heber, U.
Bibcode: 1998A&A...334..618D
Altcode:
  We present the results of a quantitative analysis of UV and optical
  spectra of nine PG 0122+200ls, very hot hydrogen-deficient [pre-]
  white dwarfs, by means of line blanketed NLTE model atmospheres. Four
  programme stars constitute the GW Vir variables, a class of non-radial
  g-mode pulsators. Precise effective temperatures, carbon, nitrogen and
  oxygen abundances and spectroscopic masses are used to constrain the
  GW Vir pulsations. The blue edge of the instability strip is at 140
  000 K (PG 1159-035). PG 0122+200 sets the red edge at 80 000 K, but
  is also one of the coolest PG 0122+200ls\ known, suggesting that the
  pulsations are stopped when the transformation of a PG 1159 star into
  a hot white dwarf occurs by gravitational settling of the metals. Four
  non-variables are found to lie inside the GW Vir instability strip
  indicating that an additional parameter determines whether a PG 1159
  star pulsates. Abundances of C and O in the pulsating stars appear to
  be higher than in the non-variables in agreement with the theoretical
  prediction that the pulsations are driven by cyclic ionization of C
  and O. The outstanding discovery of our investigation, however, is a
  strong correlation between the nitrogen abundance and pulsations. All GW
  Vir stars are nitrogen rich, whereas no nitrogen can be detected in the
  non-variables except in PG 1144+005. We conjecture that this correlation
  provides a key for the understanding of the driving mechanism. Comparing
  their position in the T_eff-log g diagram to new evolutionary models
  we conclude that most programme stars are post-AGB stars of rather low
  mass (0.5 ... 0.65 M_sun) which have lost their entire hydrogen-rich
  envelope and part of their helium-rich envelope whereas we confirm
  HS 0704+6153 to be an AGB manquestar. The high nitrogen abundance in
  four stars is a tracer of mixing processes which have led to ingestion
  and burning of hydrogen during the final helium shell flash. Based
  on observations obtained a) with the NASA/ESA Hubble Space Telescope,
  obtained at the Space Telescope Science Institute, which is operated
  by the Association of Universities for Research in Astronomy, Inc.,
  under NASA contract NAS 5-26555; b) at the German-Spanish Astronomical
  Center, Calar Alto, operated by the Max-Planck-Institut für Astronomie
  Heidelberg jointly with the Spanish National Commission for Astronomy;
  c) at the European Southern Observatory, La Silla, Chile; d) with the
  International Ultraviolet Explorer (IUE).

Title: The Pulsating ``HYBRID'' PG 1159 Star HS 2324+3944: Past,
    Present and Future
Authors: Handler, G.; Dreizler, S.; Silvotti, R.; Xiao-Jun, Jiang
Bibcode: 1998BaltA...7..105H
Altcode: 1998OAst....7..105H
  We review past efforts to unravel the nature of the light variations
  of the ``hybrid'' PG 1159 star HS 2324+3944 and present preliminary
  results of a recent multisite campaign devoted to this interesting
  object. From the on-line frequency analysis of our measurements, we can
  safely conclude that this star is a multimode pulsating variable. Some
  suggestions for further investigations are given.

Title: On the inclination and binarity of the pulsating pre-white
    dwarf PG 2131+066
Authors: Paunzen, Ernst; Konig, Michael; Dreizler, Stefan
Bibcode: 1998A&A...331..162P
Altcode:
  We report on new spectroscopic data as well as recent results from
  a temporal analysis of PG 2131+066 WET time series, yielding a new
  interpretation of the binarity nature for PG 2131+066. The newly
  discovered Hα emission features, the estimated low inclination and
  the found 3.9h period, support the picture of a close binary system,
  composed of the nonradial oscillating white dwarf with a cool red
  dwarf companion. Since the spin and the orbital period are not
  yet synchronized and because PG 2131+066 has no X-ray counterpart,
  we classify it as a progenitor of a cataclysmic variable. Based on
  observations obtained at the German-Spanish Astronomical Center, Calar
  Alto, operated by the Max Planck Institut für Astronomie Heidelberg
  jointly with the Spanish National Commission for Astronomy.

Title: HST Spectroscopy of PG 1159 Stars: the Boundary of the GW
    VIR Instability Strip
Authors: Dreizler, S.
Bibcode: 1998BaltA...7...71D
Altcode: 1998OAst....7...71D
  Our recent analysis of PG 1159 stars, mainly based on the HST
  spectroscopy, is presented. The results allow several conclusions
  regarding the boundary of the GW Vir instability strip and the driving
  mechanism for these pulsations.

Title: On the mass-loss of PG1159 stars
Authors: Koesterke, L.; Dreizler, S.; Rauch, T.
Bibcode: 1998A&A...330.1041K
Altcode:
  The winds of the four PG1159 stars NGC7094, NGC246, K1-16 and
  RXJ2117.1+3412 are investigated by means of non-LTE models for
  spherically expanding atmospheres. Based on the results of recent
  plane-parallel non-LTE analyses, several individual models with various
  mass-loss rates are calculated. Synthetic profiles of the C Iv resonance
  line are compared to high resolution, high quality HST and IUE UV
  spectra in order to determine mass-loss rates of the stars and terminal
  velocities of their winds. Complex model atoms of hydrogen, helium,
  carbon and oxygen are taken into account. In contrast to previous
  studies we find from the C Iv line at 1550 Angstroms exceedingly high
  mass-loss rates of -7.6&lt;=log(dot {M}/[M_sunyr(-1) ])&lt;=-6.9 which
  are, in case of K1-16, only two times smaller than the mass-loss rates
  of [WC]-PG1159 stars. From the comparison with theoretical predictions
  of line strength and terminal wind velocity it is most likely that
  the theory of radiation driven winds is appropriate for the PG1159
  stars. The results are discussed in the light of the evolutionary
  sequence [WCL]-&gt;[WCE]-&gt;[WC]-PG1159-&gt;PG1159\= rightarrowWD,
  which is suggested for hydrogen deficient post-AGB stars. Similarities
  between the winds of PG1159 stars and the exceptional strong winds of
  [WC]-type stars lead to the assumption that the theory of radiation
  driven winds might also apply for [WCE] stars. Changes of ionization
  degrees, which might enhance the mass-loss by multi-scattering
  processes, are found in the atmospheres of [WCE] stars but not in the
  atmospheres of PG1159 stars. Partly based on observations made with
  NASA/ESA Hubble Space Telescope, obtained from the data archive at the
  Space Telescope Science Institute, which is operated by the Association
  of Universities for Research in Astronomy, Inc., under NASA contract NAS
  5-26555; Partly based on observations obtained with the IUE satellite
  from VILSPA, Spain, jointly operated by the NASA, ESA, and PPARC.

Title: HS0507+0434: a double DA degenerate with a ZZCeti component
Authors: Jordan, S.; Koester, D.; Vauclair, G.; Dolez, N.; Heber,
   U.; Hagen, H. -J.; Reimers, D.; Chevreton, M.; Dreizler, S.
Bibcode: 1998A&A...330..277J
Altcode:
  HS0507+0434 and HS2240+1234 are two new common proper motion pairs of
  DA white dwarfs, discovered by the Hamburg Quasar Survey. Our model
  atmosphere analysis shows that HS0507+0434A has an effective temperature
  of 20000K and is remarkably young (tau_cool &lt; 1Gyr) compared to the
  average cooling time of all known wide double degenerates (~ 3Gyr). The
  cooler B component of HS0507+0434 is particularly interesting; the
  determination of the atmospheric parameters is complicated by the
  strong dependence of the solution on the details of the treatment of
  convection. Only those parameterizations of mixing length theory are
  consistent with all observations (especially the magnitude difference
  between the components), which lead to an intermediate efficiency of the
  convective flux. In the standard version of the mixing length theory
  this corresponds to a mixing length parameter of l/H_p = 1.75 - 2.0,
  where H_p is the pressure scale height. This result does not depend on
  the model atmosphere code and is in agreement with previous studies of
  convection in DA white dwarfs; there are, however, slightly different
  formulations of the MLT in use, which achieve the same efficiency at
  different values of l/H. These versions are discussed and compared
  in the paper. The result of our analysis (T_eff=11900K, log g=8)
  places the B component into the ZZCeti instability strip, where DA
  white dwarfs are pulsating non-radially. Photometric observations
  have now confirmed that HS0507+0434 is variable and identified 3 or
  4 fundamental g-modes in the Fourier spectrum. Based on observations
  collected at the German-Spanish Astronomical Center (DSAZ) at Calar
  Alto, Spain, at the European Southern Observatory, La Silla, Chile,
  with the International Ultraviolet Explorer Satellite, and at the
  Observatoire de Haute Provence (CNRS), France.

Title: Iron and Nickel Abundances in DA White Dwarfs and SDO Stars
Authors: Werner, K.; Dreizler, S.; Haas, S.; Heber, U.
Bibcode: 1998ESASP.413..301W
Altcode: 1998uabi.conf..301W
  No abstract at ADS

Title: White Dwarfs in the Hamburg Quasar Survey
Authors: Homeier, D.; Koester, D.; Hagen, H. -J.; Jordan, S.; Heber,
   U.; Engels, D.; Reimers, D.; Dreizler, S.
Bibcode: 1998AGAb...14..148H
Altcode: 1998AGM....14..P98H
  The spatial distribution and the luminosity function of white dwarfs
  provide important information on stellar evolution and the structure
  and age of the Galactic disk. A total of about 2 200 white dwarfs is
  known to date. The Hamburg Quasar Survey (HQS) has the capability to
  substantially enlarge this number and to provide an optically selected
  sample of white dwarfs not relying on EUV/X-ray emission. The HQS,
  covering 14 000 deg^2 of the northern sky, has produced objective prism
  spectra of several thousand stellar UV-excess sources. We expect to be
  able to identify 2 000-3 000 white dwarfs down to a limiting magnitude
  of B=17_{\cdot}<SUP>m</SUP>5 from this database. The spectra also
  allow a rough estimate of T<SUB>eff</SUB> by the Balmer line strengh
  of DA white dwarfs. Follow-up observations of hot star candidates
  in selected fields of the survey and comparisons with the catalogue
  of known white dwarfs have shown that DAs with temperatures down to,
  and below, the ZZ-Ceti instability strip (~ 11 000 K) are found. The
  number density of DA per deg^2 found within the magnitude range of the
  Palomar-Green survey (B &lt;= 16_{\cdot}<SUP>m</SUP>4) was higher than
  estimated from that survey. The 80 DA white dwarfs discovered by the
  follow-up spectroscopy have been analyzed using LTE model atmospheres to
  determine T<SUB>eff</SUB> and \log g, from which the mass distribution,
  luminosities and photometric distances can be derived.

Title: Photospheric metals in hot DA white dwarfs
Authors: Wolff, B.; Koester, D.; Dreizler, S.; Haas, S.
Bibcode: 1998A&A...329.1045W
Altcode:
  Previous observations of the soft X-ray and EUV region with the
  Einstein, EXOSAT, and ROSAT satellites have indicated the presence
  of photospheric absorbers in most DA white dwarfs with {T_eff}
  ga 40000K. Several of these objects have now been observed with the
  Extreme Ultraviolet Explorer (EUVE). Since the detection of individual
  metal lines is rather difficult with EUVE spectra we chose the well
  studied DA G191-B2B as reference object for the analysis of other white
  dwarfs. In spectra obtained with the GHRS of the Hubble Space Telescope
  photospheric lines of nitrogen, silicon, iron, and nickel could be
  detected. With the abundances determined from these observations we were
  able to reproduce the EUVE spectrum of G191-B2B. The main source of EUV
  opacity turned out to be iron, followed by nickel. The analysis of both
  the EUV continuum and the hydrogen Balmer lines led to {T_eff} = 56000
  +/- 2000K. For the analysis of other DA white dwarfs we used the same
  relative abundances as for G191-B2B but introduced a free scaling factor
  (``metallicity'') for the total amount of metals. From EUVE spectra
  we determined relative metallicities for 20 objects with {T_eff} ga
  40000K. The main result is that all DAs with {T_eff} ga 50000K contain
  additional photospheric absorbers, whereas at lower temperatures all
  observations, with the exception of GD394, are compatible with pure
  hydrogen atmospheres. As in the case of G191-B2B, iron determines
  also the EUV opacity in the objects at {T_eff} ga 50000K. This is in
  agreement with radiative levitation theory which predicts the support
  of iron above this temperature. Based on observations with the HST and
  EUVE satellites, and on optical spectra obtained at the DSAZ Calar Alto

Title: On the Red Edge of the GW Virginis Instability Strip
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.
Bibcode: 1998ASPC..135..130W
Altcode: 1998hcsp.conf..130W
  GW Vir (alias PG1159-035) is the prototype of a spectroscopic class of
  extremely hot hydrogen-deficient (pre-) White Dwarfs. The prototype
  as well as a number of other PG1159 stars define the GW Vir (or DOV)
  instability strip in the HR diagram. Considerable effort has been made
  to confine the limits of this instability strip by both, pulsational
  theory (Kawaler and collaborators) as well as by spectroscopic analysis
  (Werner and collaborators). Our first analysis of the prototype (Werner,
  Heber, Hunger 1991 A&amp;A 244, 437) revealed the peculiar surface
  abundances which entered as an essential ingredient into the pulsational
  analysis of Whole Earth Telescope (WET) observations (Kawaler &amp;
  Bradley 1994, ApJ 427, 415). We succeeded in constraining the blue edge
  of the instability strip (Werner et al. 1996, IAU Coll. 155, p. 96). We
  now present non-LTE model atmosphere analyses of RcoolS (Teff &lt;
  100,000K) PG1159 stars based on latest UV spectra obtained with the
  Hubble Space Telescope, aiming at the red edge of the instability
  strip. Preliminary results indicate that the red edge is much less
  well defined and seems to depend rather sensitively on photospheric
  and stellar parameters. The analysis comprises one pulsator which was a
  target of a WET observation run and it will support the interpretation
  of asteroseismologic analyses.

Title: Photospheric metals in hot DA white dwarfs.
Authors: Wolff, B.; Koester, D.; Dreizler, S.; Haas, S.
Bibcode: 1997AGAb...13..218W
Altcode:
  No abstract at ADS

Title: (Erratum) On the hot ends of the white dwarf spectral
sequences: white dwarfs containing helium from the Hamburg-Schmidt
    survey.
Authors: Heber, U.; Dreizler, S.; Hagen, H. -J.
Bibcode: 1997A&A...319..363H
Altcode:
  Erratum to Astron. Astrophys. 311, L17 (1996).

Title: Spectral Analyses of PG 1159 Stars with Line-Blanketed Non-Lte
    Model Atmospheres
Authors: Werner, K.; Dreizler, S.; Rauch, T.; Heber, U.
Bibcode: 1997fbs..conf..227W
Altcode: 1997LDP....22..227W
  No abstract at ADS

Title: Analysis of hydrogen rich PG 1159 central stars of Planetary
    Nebulae
Authors: Dreizler, S.; Werner, K.; Heber, U.
Bibcode: 1997IAUS..180..103D
Altcode:
  No abstract at ADS

Title: NLTE analyses of PG 1159 stars: constraints for the structure
    and evolution of post-AGB stars.
Authors: Dreizler, S.; Werner, K.; Rauch, T.; Heber, U.; Reid, I. N.;
   Koesterke, L.
Bibcode: 1997IAUS..189..369D
Altcode: 1998IAUS..189..369D
  The majority of all stars (M<SUB>i</SUB> &lt; 8M<SUB>sun</SUB>)
  end their lives as white dwarfs (WD). On the tip of the Asymptotic
  Giant Branch (AGB) the star ejects its outer layers which become a
  planetary nebula and the stellar core evolves rapidly towards very high
  effective temperatures (T<SUB>eff</SUB> &gt; 100 kK). When the nuclear
  burning in the H or He shell ceases the star enters the WD cooling
  sequence. The evolution starting from the AGB is separated in a H-rich
  and a H-deficient sequence where the latter contributes with a number
  fraction of ≍20%. In this paper the authors describe their recent
  effort in the analysis of one group of these stars, the PG 1159 stars.

Title: Abundance Patterns of Iron and Nickel in SDO Stellar
    Atmospheres
Authors: Haas, Stefan; Heber, Ulrich; Dreizler, Stefan; Werner, Klaus
Bibcode: 1997fbs..conf..177H
Altcode: 1997LDP....22..177H
  No abstract at ADS

Title: Ultraviolet Spectroscopy of Hot Compact Stars.
Authors: Werner, K.; Dreizler, S.; Heber, U.; Kappelmann, N.; Kruk,
   J.; Rauch, T.; Wolff, B.
Bibcode: 1997RvMA...10..219W
Altcode:
  No abstract at ADS

Title: On the fate of born-again red giants.
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.
Bibcode: 1997seas.conf..163W
Altcode: 1997ase..work..163W
  Post-AGB stars which are burning hydrogen in a shell and hot white
  dwarfs may suffer a final helium shell flash. Subsequently the stellar
  envelope re-expands and the star becomes a "born-again" red giant. What
  is the consequence for the chemistry in the envelope? In particular,
  what surface abundances can be expected and how are they affected by
  mass loss during the second descent from the AGB? Iben and MacDonald
  (1995) provided the only appropriate theoretical calculation available
  up to now for this scenario. The authors present here the results of
  spectroscopic analyses from hot H-deficient stars, which they believe
  to have undergone a late helium flash. The surface abundance pattern
  strongly varies from star to star. An explanation of this variety
  demands extensive parameter studies in evolutionary calculations.

Title: Trace Elements in White Dwarfs
Authors: Koester, Detlev; Wolff, Burkhard; Jordan, Stefan; Dreizler,
   Stefan
Bibcode: 1997fbs..conf..313K
Altcode: 1997LDP....22..313K
  No abstract at ADS

Title: New Spectral analyses of pre-white dwarfs
Authors: Rauch, T.; Dreizler, S.; Werner, K.
Bibcode: 1997ASSL..214..221R
Altcode: 1997whdw.work..221R
  No abstract at ADS

Title: Apparently Normal o- and B-Type Stars at High Galactic
    Latitudes?
Authors: Heber, U.; Moehler, S.; Schmidt, J. H. K.; Dreizler, S.;
   Geffert, M.; Reid, I. N.
Bibcode: 1997fbs..conf...87H
Altcode: 1997LDP....22...87H
  No abstract at ADS

Title: Non-LTE analyses of DO white dwarfs
Authors: Dreizler, S.; Werner, K.
Bibcode: 1997ASSL..214..213D
Altcode: 1997whdw.work..213D
  No abstract at ADS

Title: New results on PG 1159 stars and ultrahigh-excitation DO
    white dwarfs
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.
Bibcode: 1997ASSL..214..207W
Altcode: 1997whdw.work..207W
  No abstract at ADS

Title: Do White Dwarfs
Authors: Dreizler, S.; Werner, K.; Heber, U.; Reid, N.; Hagen, Hans
Bibcode: 1997fbs..conf..303D
Altcode: 1997LDP....22..303D
  No abstract at ADS

Title: New Results from the Stellar Component of the Hamburg Schmidt
Survey: a Sample of SDO Stars
Authors: Lemke, M.; Heber, U.; Napiwotzki, R.; Dreizler, S.; Engels, D.
Bibcode: 1997fbs..conf..375L
Altcode: 1997LDP....22..375L
  No abstract at ADS

Title: The extreme-ultraviolet spectrum of the central star of the
    planetary nebula NGC 1360
Authors: Hoare, Melvin G.; Drake, Jeremy J.; Werner, Klaus; Dreizler,
   Stefan
Bibcode: 1996MNRAS.283..830H
Altcode:
  We have used the Extreme Ultraviolet Explorer (EUVE) to obtain the
  first EUV spectrum of the central star of a planetary nebula, that of
  NGC 1360. The photospheric spectrum shows continuum absorption edges
  due to O^4+ as well as absorption-line features. NLTE model atmospheres
  including line blanketing by iron-group elements can match the general
  level and shape of the spectrum, but are not capable of explaining all
  the observed features, precluding a detailed fit. Our solar abundance
  models require T_eff=110000K, logg=6.0 and N_H=8.5x10^19cm^-2. A new
  optical spectrum is presented and analysed with NLTE models. Stellar
  parameters in reasonable agreement with the EUV results are derived. It
  is found that many optical lines need to be considered, otherwise the
  best fits are not necessarily unique. This data set will provide a
  stern test for future NLTE models, which will need to include still
  more line blanketing before a totally satisfactory fit is obtained.

Title: Spectral analysis of hot helium-rich white dwarfs.
Authors: Dreizler, S.; Werner, K.
Bibcode: 1996A&A...314..217D
Altcode:
  We present a model atmosphere analysis of most known hot helium-rich
  white dwarfs of spectral type DO. The stars represent the non-DA white
  dwarf cooling sequence from the hot end (T_eff_=~120000K) down to
  the DB gap (T_eff_=~45000K). From medium resolution optical spectra,
  effective temperatures, surface gravities, and element abundances
  are determined by means of non-LTE model atmospheres. Compared to
  previous LTE analyses available for some of the program stars, higher
  effective temperatures are derived. The existence of the DB gap is
  confirmed. For the first time reliable surface gravities for a large
  sample of DO white dwarfs are determined. With the help of theoretical
  evolutionary tracks the DO masses are determined. We find a mean value
  of 0.59+/-0.08M<SUB>sun</SUB>_ which virtually coincides with the mean
  masses of the DA and DB white dwarfs. Hydrogen cannot be identified
  in any optical DO spectrum, which includes the former DOA prototype
  HZ21. Hence HD149499B remains the only DO white dwarf with a positive
  (FUV) detection of trace hydrogen in the photosphere. The number ratio
  of DA/non-DA white dwarfs significantly increases along the cooling
  sequence and thus corroborates the hydrogen float-up hypothesis as an
  explanation for the DB gap. From optical, IUE, and HST spectra metal
  abundances or upper limits could be derived for most DOs, allowing
  a comprehensive comparison with predictions from diffusion/radiative
  levitation calculations. A large scatter in metallicities is found,
  even among objects with similar parameters and no clear trend along
  the cooling sequence is detectable. This is severely at odds with
  theoretical predictions. The evolutionary link between DO white dwarfs,
  the PG1159 stars and DB white dwarfs is discussed, in particular
  considering the overlapping positions of DO and PG1159 stars in the
  HR diagram.

Title: Confining the edges of the GW Vir instability strip.
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.
Bibcode: 1996AGAb...12..198W
Altcode:
  No abstract at ADS

Title: On the hot ends of the white dwarf spectral sequences: Hot
    white dwarfs containing helium from the Hamburg-Schmidt survey.
Authors: Heber, U.; Dreizler, S.; Hagen, H. -J.
Bibcode: 1996A&A...311L..17H
Altcode:
  We report on the discovery of twelve very hot white dwarf stars
  containing helium by follow-up spectroscopy of candidates selected
  by the Hamburg-Schmidt survey. These stars belong to the sparsely
  populated spectral subclasses DAO, DO and PG1159 tracing the hottest
  ends of the white dwarf spectral sequences. Eight stars show helium
  dominated spectra (four DOs, two PG1159 stars and two very hot DO/sdO
  transition objects). Four stars have hydrogen dominated spectra (DAO),
  out of which one is a spectroscopic binary. Metal absorption lines
  are detected in one DO and one DAO star. The latter is unique and has
  to be classified as the first known DAOZ star. Spectral comparison
  indicates that all stars lie beyond the DB gap with T_eff_ exceeding
  45000K. Evidence is given for T_eff_ as high as 100000K or more in
  some stars. With these new discoveries the Hamburg-Schmidt survey has
  increased the number of known DO and DAO white dwarfs and PG1159 stars
  by 55%, 30% and 40%, respectively, an important step towards deriving
  statistically meaningful samples of the hottest white dwarfs.

Title: Iron and nickel abundances of subluminous
    O-stars. I. NLTE-model atmospheres with line blanketing by iron
    group elements.
Authors: Haas, S.; Dreizler, S.; Heber, U.; Jeffery, S.; Werner, K.
Bibcode: 1996A&A...311..669H
Altcode:
  NLTE model atmospheres for hot evolved stars including line blanketing
  of all iron group elements were first constructed by Dreizler &amp;
  Werner (1993). In this paper we improve computational details and check
  the adopted simplifications. We also present a systematic investigation
  of the consequences of iron group line blanketing on the atmospheric
  structure (temperature stratification and ionization equilibria of
  iron and nickel) and for various observational quantities in the case
  of hot sdO model atmospheres. The inclusion of a vast number of iron
  group lines yields a substantial flux blocking in the vicinity of the
  He{2} 228A edge. The resulting effects on the optical line profiles
  of hydrogen and helium lines are none the less marginal. The most
  pronounced differences occur in the cores of these lines, in particular
  of the He{2} 4686A line. The new models are applied to an abundance
  analysis of Fe{5}, Fe{6} and Ni{6} lines in the high resolution IUE
  spectrum of the hot sdO star BD+28 4211. An underabundance of iron by
  1dex with respect to the sun is found, while nickel displays a solar
  abundance. The reduced n_Fe_/n_Ni_ ratio (~1dex compared to the solar
  value) is an important hint that radiative levitation may hinder the
  gravitational settling of these species. It is demonstrated that the
  Fe{5}/Fe{6} ionization equilibrium is a reliable indicator for T_eff_
  consistent with results from the optical He{1}/He{2} ionization
  equilibrium routinely used for spectroscopic analyses.

Title: The Origin of the Peculiar Hybrid PG 1159 Stars
Authors: Dreizler, S.
Bibcode: 1996hst..prop.6463D
Altcode: 1996hst..prop.2874D
  The PG 1159 stars form a new class of hydrogen deficient prewhite dwarfs
  (PWD) representing the hottest stage of PWDevolution. Quantitative
  spectral analyses of most knownPG 1159 stars have been carried out by
  the proposers fromoptical, UV (IUE, HST) and EUV (EUVE) observations. It
  hasbeen shown that these stars have atmospheres dominated by Cand
  He. In the hottest stars also a significant amount of O ispresent. The
  proposed targets, HS2324+3944, NGC7094, and Abell43define a small
  group of peculiar PG 1159 stars. Unlikeall other PG 1159 stars
  hydrogen is detected in their spectra.Stellar parameters derived by the
  investigators from opticalspectra suggest that, as a consequence of a
  lower mass, theywent through a less drastic mass-loss phase than the
  ordinaryPG 1159 stars. In order to verify that hypothesis a moreprecise
  determination of the effective temperature isrequired. This is not
  possible from optical analyses alone. Wedemonstrate that a great
  improvement on the determination ofthe effective temperatures can
  be achieved by HST-GHRSspectra. The spectra will be analyzed with new
  highlysophisticated NLTE line blanketed model atmospheres, whichallow to
  include many elements up to the iron group self-consistently. A precise
  placement of HS2324+3944, NGC7094, and Abell43in the HR-diagram holds
  the key for understanding theevolutionary history of the PG 1159 class.

Title: Discovery and analysis of a hydrogen-rich PG1159 star.
Authors: Dreizler, S.; Werner, K.; Heber, U.; Engels, D.
Bibcode: 1996A&A...309..820D
Altcode:
  The discovery of a new peculiar PG1159 star by follow-up spectroscopy of
  candidates selected from objective-prism plates of the Hamburg Schmidt
  Survey is presented. From a NLTE model atmosphere analysis an effective
  temperature of 130000+/-10000K and a surface gravity of logg=6.2+/-0.2
  are determined, which together with the high carbon abundance place
  HS2324+3944 in the region of low gravity PG1159 stars. The detection
  of hydrogen, however, makes HS2324+3944 unique amongst the PG1159
  stars. While three central stars of Planetary Nebulae have spectra
  similar to HS2324+3944, hydrogen could not be detected up to now in
  any PG1159 star not associated with a nebula. The abundances of helium,
  carbon and nitrogen (C/He=0.3, N/He&lt;2x10^-3^) are similar to that of
  "normal" PG1159 stars while the O abundance is found to be somewhat
  lower than "normal" (O/He=2-10x10^-3^).

Title: High resolution UV spectroscopy of two hot (pre-) white dwarfs
    with the Hubble Space Telescope. KPD0005+5106 and RXJ2117+3412.
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.; Fleming,
   T. A.; Sion, E. M.; Vauclair, G.
Bibcode: 1996A&A...307..860W
Altcode:
  High resolution UV spectra of KPD0005+5106 and RXJ2117+3412 have
  been obtained with the Goddard High Resolution Spectrograph aboard
  the Hubble Space Telescope. The data were subject to a non-LTE model
  atmosphere analysis. For KPD0005+5106, the hottest known helium-rich
  white dwarf, the C and N abundances as well as an upper limit for O
  have been determined (log(C/He)=-3, log(N/He)=-6, log(O/He)&lt;-5.5,
  by number), improving results from previous studies. These abundances
  are severely at odds with diffusion/radiative forces theory. They
  are possible primordial relics of their ancestral progenitor in the
  post-AGB phase. Besides the photospheric lines with a velocity shift
  of +35km/s we find a distinct interstellar/circumstellar absorption
  line system shifted by -15km/s. Difficulties are encountered with
  line profile fits to the spectrum of RXJ2117+3412, an extremely hot
  hydrogen-deficient (PG1159-type) central star. Some of the strong C
  IV and O VI lines are too narrow to match the observations. Either
  the neglect of wind-effects in our models or the lack of reliable line
  broadening data may be responsible for this. A weak O V 1371A line is
  detected which suggests, that the effective temperature is higher than
  thought before (T_eff_=170000K). This means that RXJ2117+3412 is the
  hottest known PG1159 star together with H1504+65. Interstellar and
  photospheric line spectra are clearly separated, with shifts of -19
  and +23km/s, respectively. Both stars exhibit a strong O VIII emission
  line near 2977A, which cannot be of photospheric origin but probably
  arises from shock fronts along a stellar wind. The line widths are
  of the order of 150km/s. In addition, KPD0005+5106 shows another,
  equally strong emission feature near 2982A which either stems from
  photospheric N V or from non-photospheric C V.

Title: Spectral analysis of hot helium-rich white dwarfs
Authors: Dreizler, S.; Werner, K.
Bibcode: 1996ASPC...96..281D
Altcode: 1996hds..conf..281D
  No abstract at ADS

Title: Confining the Edges of the GW VIR Instability Strip
Authors: Werner, Klaus; Dreizler, Stefan; Heber, Ulrich; Rauch, Thomas
Bibcode: 1996aeu..conf..229W
Altcode: 1996IAUCo.152..229W
  No abstract at ADS

Title: Helium-rich stars from the HS, PG and KPD surveys
Authors: Heber, U.; Dreizler, S.; Werner, K.; Engels, D.; Hagen, H. -J.
Bibcode: 1996ASPC...96..241H
Altcode: 1996hds..conf..241H
  No abstract at ADS

Title: NLTE spectral analysis of helium-rich sdO stars from the
    southern HK survey
Authors: Drilling, J. S.; Napiwotzki, R.; Dreizler, S.; Heber, U.;
   Beers, T. C.
Bibcode: 1996ASPC...96..317D
Altcode: 1996hds..conf..317D
  No abstract at ADS

Title: A catalogue of hydrogen-deficient stars
Authors: Jeffery, C. S.; Heber, U.; Hill, P. W.; Dreizler, S.;
   Drilling, J. S.; Lawson, W. A.; Leuenhagen, U.; Werner, K.
Bibcode: 1996ASPC...96..471J
Altcode: 1996hds..conf..471J
  No abstract at ADS

Title: PG 1159 stars
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.
Bibcode: 1996ASPC...96..267W
Altcode: 1996hds..conf..267W
  No abstract at ADS

Title: Ultra-high excitation features in hot white dwarfs: A DAO
    and three DO stars discovered by the Hamburg-Schmidt survey.
Authors: Dreizler, S.; Heber, U.; Napiwotzki, R.; Hagen, H. J.
Bibcode: 1995A&A...303L..53D
Altcode:
  We report on the discovery of four hot white dwarfs, one DAO
  (HS2115+1148) and three DO (HS0158+2335, HS 0727+6003 and HS
  2027+0651). The spectra of these stars exhibit shallow metal
  absorption lines from ultrahighly excited ionization stages (C V, C
  VI/N VI, N VII/O VII, O VIII, Ne IX, Ne X) with ionization energies
  ranging from 392eV to 1362eV. We propose that they are formed in a
  stellar wind, explaining their asymmetric shape. However, the He II
  line spectra of the three DOs as well as the Balmer-line spectrum
  of the DAO are peculiar and cannot be fitted by static NLTE model
  atmospheres. These stars increase the number of hot degenerate stars
  showing this phenomenon to six, this is the first time it is observed
  in a hydrogen-rich star. Thus, these six stars might constitute a new
  spectral subclass of hot white dwarfs suffering mass-loss from a hot
  and fast wind.

Title: Spectral analysis of the hot DO white dwarf PG1034+001.
Authors: Werner, K.; Dreizler, S.; Wolff, B.
Bibcode: 1995A&A...298..567W
Altcode:
  We present a non-LTE model atmosphere analysis of the hot DO white dwarf
  PG1034+001. It is based on archival HST GHRS spectra, on new optical
  medium resolution spectra and pointed ROSAT PSPC observations. The
  effective temperature is higher than previously thought (T_eff_=100000K,
  Logg=7.5). We determined abundances of carbon, nitrogen, and oxygen
  which are roughly in agreement with earlier LTE results. We also
  determined the silicon abundance and, for the first time in a DO white
  dwarf, the abundance of iron on hand of newly identified Fe VI lines in
  the HST spectra. An upper abundance limit for nickel is derived. The
  results are discussed in the framework of diffusion theory. We derive
  a stellar mass of 0.59M<SUB>sun</SUB>_ and propose that PG1034+001 is
  a descendant from the hydrogen-deficient PG1159 stars.

Title: Detection of QSO Ton S 180 by the EUVE satellite.
Authors: Wisotzki, L.; Dreizler, S.; Engels, D.; Fink, H. -H.;
   Heber, U.
Bibcode: 1995A&A...297L..55W
Altcode:
  We report the detection of the bright QSO Ton S 180 by the Extreme
  Ultraviolet Explorer satellite during its all-sky survey. The measured
  count rate is 58cts/ksec, more than any other QSO or Sy-1 listed by
  the First EUVE Source Catalog. We have compiled previously unpublished
  optical, ultraviolet, and X-ray observations of this source, and
  construct the continuum spectral energy distribution. The soft X-ray
  range is well described by a single power law with spectral energy
  index α=-2.0. Although different ROSAT pointings show that the total
  X-ray counts have varied by a factor of 3, the shape of the spectrum
  has remained unchanged. The EUVE flux is fully compatible with the
  ROSAT survey measurement, confirming that the power law shape reaches
  well into the EUV regime. No additional soft X-ray or EUV excess could
  be found. The optical-UV continuum displays a strongly convex shape,
  with a turnover in νxf<SUB>nu</SUB>_ already below 10eV. The overall
  shape of the continuum suggests that more than a single emission
  component contributes to the big blue bump.

Title: Analysis of the DO White Dwarf PG 1034+001: Solution of the
    He II 4686 Å Line Problem
Authors: Werner, Klaus; Dreizler, Stefan; Wolff, Burkhard
Bibcode: 1995LNP...443..204W
Altcode: 1995whdw.conf..204W
  No abstract at ADS

Title: Iron- and Nickel Abundances of sdO Stars
Authors: Haas, Stefan; Dreizler, Stefan; Heber, Ulrich; Meier, Thomas;
   Werner, Klaus
Bibcode: 1995LNP...443..243H
Altcode: 1995whdw.conf..243H
  No abstract at ADS

Title: Confining the Edges of the GW VIR Instability Strip
Authors: Werner, K.; Rauch, T.; Dreizler, S.; Heber, U.
Bibcode: 1995ASPC...83...96W
Altcode: 1995aasp.conf...96W; 1995IAUCo.155...96W
  No abstract at ADS

Title: Discovery of two hot DO white dwarfs exhibiting
    ultrahigh-excitation absorption lines.
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.; Wisotzki,
   L.; Hagen, H. -J.
Bibcode: 1995A&A...293L..75W
Altcode:
  We report on the detection of two faint blue stars (HE0504-2408 and
  HS0713+3958) discovered by the Hamburg Schmidt surveys whose spectra are
  dominated by broad and shallow metal absorption lines from ultrahighly
  excited ionization stages (CV, CVI/NVI, NVII/OVII, OVIII, NeIX, NeX)
  with ionization energies ranging from 392eV to 1362eV. Detailed non-LTE
  modeling excludes a photospheric origin of these lines. Instead we
  propose that they are formed in a stellar wind, explaining their
  asymmetric shape. The underlying stellar source is probably a hot
  helium-rich white dwarf (Teff about 70000K) causing the observed HeII
  line spectrum with symmetric profiles. However, the HeII absorptions are
  relatively strong and cannot simply be reproduced by a model atmosphere
  for a DO white dwarf. Thus, these two stars might constitute a new
  spectral subclass of hot helium-rich white dwarfs exhibiting spectral
  signatures never observed before in any astrophysical object.

Title: Triple-Alpha Burning Products on the Surface of Peculiar
    Post-AGB Stars
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.
Bibcode: 1995AIPC..327...45W
Altcode: 1995nct3.conf...45W
  The so-called PG 1159 stars form a new spectroscopic class of extremely
  hot hydrogen-deficient post-AGB stars. Our spectral analyses with model
  atmospheres show that their chemical surface composition is dominated
  by carbon, helium, and oxygen. We suggest that these peculiar stars
  have suffered a late helium-shell flash which has caused the removal of
  the hydrogen-rich envelope and even most of the helium-rich intershell
  matter. The idea that the former helium-burning region is now exposed at
  the surface of the PG 1159 stars is supported by the recent detection
  of a very high amount of neon in some objects. The most extreme object
  is H1504+65 which is one of the brightest X-ray sources in the sky
  and the hottest star ever analyzed with model atmosphere techniques
  (T<SUB>eff</SUB>=170 000 K). The photosphere is devoid of hydrogen and
  helium and composed of oxygen and carbon by equal amounts! This means
  that we look at the naked core of the former Red Giant. This gives us
  the unique possibility to confine empirically the still uncertainty
  known <SUP>12</SUP>C(α,γ)<SUP>16</SUP>O nuclear reaction rate.

Title: Detection of Ultra-Hot Pre-White Dwarfs?
Authors: Werner, Klaus; Rauch, Thomas; Dreizler, Stefan; Heber, Ulrich
Bibcode: 1995LNP...443..171W
Altcode: 1995whdw.conf..171W
  No abstract at ADS

Title: The EUVE spectrum of the hot DA white dwarf PG 1234+482
Authors: Jordan, Stefan; Koester, Detlev; Finley, David; Werner,
   Klaus; Dreizler, Stefan
Bibcode: 1995LNP...443..332J
Altcode: 1995whdw.conf..332J
  We have analyzed the EUVE spectrum of PG 1234+482 with fully blanketed
  model atmospheres taking into account several million lines of heavy
  elements. Most of the spectral features in the short (SW) and medium
  (MW) wavelength spectrum can be identified with lines of iron, nickel
  and calcium ions.

Title: PG 1159 Stars and Their Evolutionary Link to DO White Dwarfs
Authors: Dreizler, Stefan; Werner, Klaus; Heber, Ulrich
Bibcode: 1995LNP...443..160D
Altcode: 1995whdw.conf..160D
  No abstract at ADS

Title: Stratification of helium in the photospheres of the helium-weak
    stars HD 28843 and HD 49333.
Authors: Farthmann, M.; Dreizler, S.; Heber, U.; Hunger, K.
Bibcode: 1994A&A...291..919F
Altcode:
  For four helium-weak and variable B stars phase-dependent
  high-resolution spectrograms have been obtained with the
  Echelec-spectrograph attached to the 1.5 m ESO telescope, with the
  aim of testing whether HeI 4471A will give evidence of chemical
  stratification within their photospheres. Of the four candidates, HR
  3448=HD 74196 is a fast rotator (vsini=300km/s), however, no variability
  is detectable, while HR 1100=HD 22470 does not exhibit any helium line
  (posibly due to incomplete phase coverage). Only HR 1441=HD 28843 and
  HR 2509=HD 49333 are genuine helium variables. Profile analyses of
  HeI 4471, based on fully line blanketed model atmospheres which are
  adapted to the relevant helium-content show that HD 28843 can fully be
  explained by a cap model with two asymmetrically located helium caps
  of equal radii. For HD 49333 vertical stratification in addition has
  to be assumed in order to explain the excessively broad wings. This
  confirms earlier (preliminary) results by Groote et al. (see Hunger
  1986). Vertical stratification is infered for both inside and outside
  the helium-caps of HD 49333.

Title: On the nickel abundance in hot hydrogen-rich white dwarfs.
Authors: Werner, K.; Dreizler, S.
Bibcode: 1994A&A...286L..31W
Altcode:
  We present a non-LTE iron and nickel abundance analysis of four
  hot hydrogen rich white dwarfs from high resolution IUE spectra. The
  investigation aims at the determination of the Ni/Fe ratio in order to
  investigate if radiative acceleration prevents gravitational settling of
  both elements. We succeeded in the first identification of nickel lines
  in white dwarfs. In fact we find enhanced Ni/Fe ratios (compared to the
  solar value) in the two extremely iron rich (for white dwarf standards)
  stars RE0623--377 and RE2214--2 The effect is slightly smaller in the
  other two objects considered (G191-B2B and Feige24). This is regarded
  as evidence that radiation pressure acting through the huge number
  of spectral lines is responsible for radiative levitation of iron
  and nickel.

Title: A "cool" PG 1159 star discovered by the Hamburg Schmidt Survey:
    NLTE analysis of HS 0704+6153.
Authors: Dreizler, S.; Werner, K.; Jordan, S.; Hagen, H.
Bibcode: 1994A&A...286..463D
Altcode:
  The discovery of a new PG 1159 star by follow-up spectroscopy of
  candidates selected from objective-prism plates of the Hamburg Schmidt
  Survey is presented. From a NLTE model atmosphere analysis an effective
  temperature of 65 000 K and a surface gravity of logg=7.0 is determined,
  which together with the extreme helium abundance (H/He&lt;1 by number)
  place HS 0704+6153 in the region of hot DO white dwarfs. The high carbon
  and oxygen abundances (C/He=0.2, O/He~0.05 by number), however, are
  typical for PG 1159 stars. Its effective temperature is by far lower
  than that of any other PG 1159 star. HS 0704+6153 therefore is in the
  transition stage between the PG 1159 stars and the DO white dwarfs,
  it hence is an ideal object to study the gravitational settling of
  metals in helium-rich atmospheres.

Title: PG 2120+062 : an apparently normal O-star at high galactic
    latitude.
Authors: Moehler, S.; Heber, U.; Dreizler, S.
Bibcode: 1994A&A...282L..29M
Altcode:
  We report the spectroscopic identification of the faint blue star PG
  2120+062 (V = 14.4 m) as an apparently normal O9 star. If massive, PG
  2120+062 would be at a distance of 50 kpc and 25 kpc below the galactic
  plane. T<SUB>eff</SUB> = 38000 K, log g = 4.25 results from a nonlocal
  thermodynamic equilibrium (NLTE) model atmosphere analysis. PG 2120+062
  could, however, also be a low mass post-AGB star at a distance of 5 kpc
  that mimics a normal O star spectroscopically. Variable H-alpha emission
  is interpreted as due to a circumstellar disk (Be star phenomenon) or
  a close companion star. In the latter case, the primary to secondary
  mass ratio would be very large M<SUB>p</SUB>/M<SUB>s</SUB> greater
  than 7) and PG 2120+062 could be the progenitor of a symbiotic star
  or a cataclysmic variable.

Title: PG 1159 stars and their evolutionary link to DO white dwarfs.
Authors: Dreizler, S.; Werner, K.; Heber, U.
Bibcode: 1994AGAb...10...62D
Altcode:
  No abstract at ADS

Title: PG 2120+062: an apparently normal O-star at high galactic
    latitude.
Authors: Moehler, S.; Heber, U.; Dreizler, S.
Bibcode: 1994AGAb...10...34M
Altcode:
  No abstract at ADS

Title: Faint Blue Stars from the Hamburg Schmidt Survey
Authors: Dreizler, Stefan; Heber, Uli; Jordan, S.; Engels, D.
Bibcode: 1994hsgh.conf..228D
Altcode:
  No abstract at ADS

Title: On the Evolutionary Link Between the PG 1159 Stars and the
    DO White Dwarfs
Authors: Dreizler, S.
Bibcode: 1994iue..prop.4896D
Altcode:
  No abstract at ADS

Title: Quantitative Spectroscopy of the Very Hot Subluminous O-Stars:
    K648 PG1159-035, and KPD0005+5106
Authors: Heber, Ulrich; Dreizler, Stefan; Werner, Klaus
Bibcode: 1994hsgh.conf..187H
Altcode:
  No abstract at ADS

Title: Detection of a possible new ultra-hot pre-white dwarf.
Authors: Werner, K.; Dreizler, S.; Heber, U.; Rauch, T.; Wisotzki, L.
Bibcode: 1994AGAb...10...58W
Altcode:
  No abstract at ADS

Title: Line blanketing by iron group elements in non-LTE model
    atmospheres of hot stars.
Authors: Dreizler, S.; Werner, K.
Bibcode: 1994ems..conf..147D
Altcode:
  The authors report on their recent progress in modeling non-LTE
  atmospheres of O-stars including blanketing by lines from the iron
  group elements. The numerical method to account for the huge number of
  atomic levels and line transitions is presented. Results of exploratory
  model calculations examining the effects on the temperature structure,
  the hydrogen and helium line profiles and UV/EUV fluxes are discussed.

Title: Quantitative Spectroscopy of K 648 --the PNN of Ps1 in the
    Globular Cluster M15
Authors: Heber, Ulrich; Dreizler, Stefan; Werner, Klaus
Bibcode: 1993AcA....43..337H
Altcode:
  We report preliminary results of a quantitative study of high resolution
  UV and optical spectra of K648 obtained with the Hubble Space Telescope
  and the Calar Alto 3.5 m telescope, respectively. Using state of the
  art NLTE model- atmospheres we determine atmospheric parameters and the
  abundances of hydrogen, helium and carbon. K648 is found to be helium-
  and carbon-rich when compared to solar composition.

Title: Two New Extremely Iron-rich Hot DA White Dwarfs and the Nature
    of the EUV Opacity
Authors: Holberg, J. B.; Barstow, M. A.; Buckley, D. A. H.; Chen,
   A.; Dreizler, S.; Marsh, M. C.; O'Donoghue, D.; Sion, E. M.; Tweedy,
   R. W.; Vauclair, G.; Werner, K.
Bibcode: 1993ApJ...416..806H
Altcode:
  We have obtained IUE echelle spectra of two bright extreme ultraviolet
  (EUV) sources discovered by the ROSAT wide field camera all-sky
  survey. These stars, RE 2214-492 and RE 0623-377, are previously
  uncataloged hot DA white dwarfs with respective apparent visual
  magnitudes of 11.71 and 12.09 and exhibit short-wavelength EUV cutoffs
  steeper than most other DAs. The IUE echelle spectra are rich in
  absorption lines due to a large number of Fe V and Fe VI features, in
  addition to the highly ionized C, N, O ions frequently seen in other
  hot DA white dwarfs. No He is observed in either star. Comparison
  of RE 2214-492 and RE 0623-377 with two well-studied hot DA white
  dwarfs, G191 B2B and Feige 24, indicates that these new stars are
  both significantly hotter and more metal-rich than G191 B2B and Feige
  24. From optical and UV line profiles we find T<SUB>eff</SUB> = 63,500
  K and 60,300 K for RE 2214-492 and RE 0623-377, respectively. From
  modeling of Fe V features in the echelle spectra we find corresponding
  Fe abundances of log [N(Fe)/ n(H)] = -4.25±0.25. The association
  of steep EUV cutoffs in these stars, and in G191 B2B and Feige 24,
  with the observed presence of Fe suggests that iron-group elements
  along with other heavy elements are responsible for much of the EUV
  opacity observed by ROSA T in the hottest DA stars.

Title: Line blanketing by iron group elements in non-LTE model
    atmospheres for hot stars.
Authors: Dreizler, S.; Werner, K.
Bibcode: 1993A&A...278..199D
Altcode:
  We present the first metal line blanketed non-Local Thermodynamic
  Equilibrium (LTE) model atmospheres for O stars which include 130,000
  lines of the iron group elements scandium through nickel, a subset
  from Kurucz' (1991) line list, fully self-consistently. It is shown
  that even the treatment of the complete line list (greater than
  10<SUP>6</SUP> lines) in NLTE models poses no longer any fundamental
  problem. The numerical solution of the metal line blanketing problem
  consists of an opacity sampling technique within the framework of
  the Accelerated Lambda Iteration method. Exploratory models with
  different parameters were successfully constructed, e.g. for hot
  subdwarfs and central stars of planetary nebulae as well as for white
  dwarfs. We discuss the blanketing effects of metal lines (1) onto the
  atmospheric stratification, (2) onto UV and EUV fluxes, (3) onto the
  emergent H and He line profiles, and (4) the potential of iron lines
  as sensitive temperature indicators. The models are used to interprete
  EUV observations of the white dwarf G191-B2B and UV spectra of the
  hot sdO star BD+28 deg 4211.

Title: Metal Line Blanketed Non-LTE Model Atmospheres for Planetary
    Nebula Nuclei
Authors: Werner, K.; Dreizler, S.
Bibcode: 1993AcA....43..321W
Altcode:
  We report on our recent progress in modeling non-LTE central
  star atmospheres including blanketing by lines from the iron group
  elements. It is found that the spectroscopic analysis of the hottest
  stars (T<SUB>eff</SUB> approx 90,000 K) based on hydrogen Balmer and
  HeII lines is hardly affected by metal opacities in the models. As a
  consequence, results from earlier analyses based on models composed
  of hydrogen and helium only remain essentially unchanged.

Title: Spectral analysis of extremely helium rich subdwarfs O-stars.
Authors: Dreizler, S.
Bibcode: 1993A&A...273..212D
Altcode:
  The NLTE analyses of four extremely helium rich sdO stars based on
  high resolution, high S/N CASPEC spectra are presented. Effective
  temperatures, gravities and the abundances of H, He, C, N, O, Ne, Mg,
  and Si have been deter- mined. It is found that LS<SUB>IV</SUB>+1O°9,
  LSS 1274, and UV 0832-01 have very similar parameters: T<SUB>eff</SUB>
  = 44500±1000 K, log g = 5.55±0.15. H is undetected in all programme
  stars resulting in a upper limit of n<SUB>H</SUB>/n<SUB>He</SUB> ≤
  0.1. C, N, and Ne are enriched, while Mg and Si are solar and O is
  slightly depleted. Microturbulent velocity is found to be lower than to
  km/s. The positions of these stars in the (log T<SUB>eff</SUB>,log g)
  diagram indicate, that they are post-EHB (Extended Horizontal Branch)
  stars. Their atmospheric composition can be understood as a mixture
  of CNO and 3 - α processed material. UV 0904-02 is slightly hotter,
  T<SUB>eff</SUB> = 46500±1000 K, log g = 5.55±0.15, and is as well
  a post-EHB star. The atmosphere also displays a mixture of CNO and
  3-α processed material, the primordial metallicity however, was
  possibly lower.

Title: Line blanketing by iron group elements in non-LTE model
    atmospheres of hot stars
Authors: Dreizler, Stefan; Werner, Klaus
Bibcode: 1993SSRv...66..147D
Altcode:
  We report on our recent progress in modeling non-LTE atmospheres of
  O-stars including blanketing by lines from the iron group elements. The
  numerical method to account for the huge number of atomic levels and
  line transitions is presented. Results of exploratory model calculations
  examining the effects on the temperature structure, the hydrogen and
  helium line profiles and UV/EUV fluxes are discussed.

Title: Faint blue stars from the Hamburg Schmidt Survey.
Authors: Dreizler, S.; Heber, U.; Jordan, S.
Bibcode: 1993AGAb....9..152D
Altcode:
  No abstract at ADS

Title: Metal Line Blanketed Non-LTE Model Atmospheres for Central
    Stars of Planetary Nebulae
Authors: Werner, K.; Dreizler, S.
Bibcode: 1993IAUS..155...83W
Altcode:
  No abstract at ADS

Title: Line blanketing by iron group elements in non-LTE model
    atmospheres for hot stars.
Authors: Haas, S.; Dreizler, S.; Werner, K.
Bibcode: 1993AGAb....9..153H
Altcode:
  No abstract at ADS

Title: High resolution optical and UV spectroscopy of the central
    star of K648.
Authors: Heber, U.; Dreizler, S.; Werner, K.
Bibcode: 1993AGAb....9...70H
Altcode:
  No abstract at ADS

Title: Metal line blanketing in non-LTE model atmospheres
Authors: Dreizler, S.; Werner, K.
Bibcode: 1993ASIC..403..205D
Altcode: 1993wdao.conf..205D
  No abstract at ADS

Title: NLTE analysis of extremely helium rich subdwarf O stars
Authors: Dreizler, S.
Bibcode: 1993ASIC..403..287D
Altcode: 1993wdao.conf..287D
  No abstract at ADS

Title: High Resolution UV Spectroscopy of 3 Metal Weak LIned SdO Stars
Authors: Dreizler, S.
Bibcode: 1993iue..prop.4737D
Altcode:
  No abstract at ADS

Title: NLTE analysis of helium rich subdwarf O stars
Authors: Dreizler, S.
Bibcode: 1992LNP...401..270D
Altcode: 1992aets.conf..270D
  No abstract at ADS

Title: Iron line blanketing in NLTE model atmospheres for O stars:
    First results
Authors: Dreizler, S.; Werner, K.
Bibcode: 1992LNP...401..436D
Altcode: 1992aets.conf..436D
  No abstract at ADS

Title: Non-Lte Model Atmosphere Calculations with Approximate Lambda
    Operators
Authors: Dreizler, S.; Werner, K.
Bibcode: 1991ASIC..341..155D
Altcode: 1991sabc.conf..155D
  No abstract at ADS

Title: Non-LTE Sternatmosphärenmodelle für heliumreiche Sterne
des Spektraltyps sd0 Title: Non-LTE Sternatmosphärenmodelle für
heliumreiche Sterne des Spektraltyps sd0 Title: Non-LTE stellar
    atmosphere models for helium-rich stars of spectral type sd0;
Authors: Dreizler, Stefan
Bibcode: 1991PhDT.......156D
Altcode:
  No abstract at ADS

Title: Hot subluminous stars at high galactic latitudes. III. Non-LTE
    analysis of extremely helium rich sdO-stars.
Authors: Dreizler, S.; Heber, U.; Werner, K.; Moehler, S.; de Boer,
   K. S.
Bibcode: 1990A&A...235..234D
Altcode:
  The visual spectra of 15 extremely helium rich subdwarf O-stars are
  analyzed. Effective temperatures and gravities are determined by means
  of a new grid of helium and hydrogen line-blanketed non-LTE model
  atmospheres calculated with the accelerated lambda iteration. Effective
  temperatures cluster around 45,000 K and 65,000 K. Gravities range
  from log g = 4.8 to log g = 6.0. Hydrogen is detected in 5 stars. Upper
  limits to the hydrogen content are derived for the others. From these
  spectroscopic results first conclusions about the evolutionary status
  of these stars can be drawn. The program stars probably evolve from
  the extended or blue horizontal branch. Mixing induced by thermal
  pulses might account for the helium enrichment.

Title: NLTE model atmospheres for He-rich sdO-stars.
Authors: Dreizler, S.; Heber, U.; Werner, K.
Bibcode: 1990AGAb....5...16D
Altcode:
  No abstract at ADS

Title: Non-LTE model atmospheres for hot evolved stars.
Authors: Werner, K.; Dreizler, S.; Heber, U.; Hunger, K.; Rauch, T.
Bibcode: 1990nba..meet..379W
Altcode: 1990taco.conf..379W
  During the last years the authors have developed a computer code
  to construct non-LTE model atmospheres for hot stars including
  line blanketing effects. The particular methods gave way to the
  computation of non-LTE model atmospheres which account for many more
  opacity sources than could be treated within the classical complete
  linearisation approach by Auer and Mihalas. With this code it became
  possible for the first time to calculate grids of realistic non-LTE
  line blanketed model atmospheres for subdwarf O-stars in a critical
  temperature range as well as for the extremely hot (100,000K to
  150,000K) so-called PG1159 stars. Both groups of stars consist of
  objects being in advanced evolutionary stages representing immediate
  White Dwarf progenitors. The atmospheres of these stars are enriched or
  even dominated by nuclear processed material, namely either by helium
  (sdO stars) or also by carbon and oxygen (PG1159 stars).

Title: NLTE-analysis of extremely helium-rich sd0 stars
Authors: Dreizler, S.; Heber, U.; Werner, K.; de Boer, K. S.;
   Moehler, S.
Bibcode: 1989AGAb....3...45D
Altcode:
  No abstract at ADS

Title: NLTE-analysis of extremely helium-rich sdO-stars.
Authors: Dreizler, S.; Heber, U.; Werner, K.; de Boer, K. S.;
   Moehler, S.
Bibcode: 1989AGAb....3...44D
Altcode:
  No abstract at ADS

Title: Spectroscopy of helium-rich subluminous O and B stars.
Authors: Heber, U.; Dreizler, S.; de Boer, K. S.; Moehler, S.;
   Richtler, T.
Bibcode: 1988AGAb....1...16H
Altcode:
  No abstract at ADS

