Author name code: thompson-michael
ADS astronomy entries on 2022-09-14
author:"Thompson, Michael J." 
------------------------------------------------------------------------  

Title: Self-Reported Demographics of 2014–2021 Principle
    Investigators Proposing to NASA Planetary Science Research Programs
Authors: Thompson, M.; Jensen, H. B.; Papas, L. L.; Taha, N.; New,
   M. H.
Bibcode: 2022LPICo2679.2049T
Altcode:
  The NASA Division of Planetary Science will present demographic data
  of Principle Investigators proposing to Research Opportunities in
  Space and Earth Sciences (ROSES) programs for the years 2014–2021.

Title: Improving Idea Through Nasa's Planetary Science Division's
    Proposal Processes
Authors: Daou, D.; Moore, L.; Nahm, A. L.; Rinehart, S. A.;
   Santiago-Materese, D.; Thompson, M.; Vander Kaaden, K. E.; Watkins,
   R. N.; Zellner, N.
Bibcode: 2022LPICo2679.2043D
Altcode:
  NASA, including the Planetary Science Division, is strongly
  committed to promoting a culture of inclusion, diversity, equity,
  and accessibility. A multitude of actionable efforts are underway to
  increase IDEA throughout the proposal process.

Title: Possible Mechanism(s) in the Photo-Magnetic Production of
    Enantiomer Excesses
Authors: Cooper, G.; Jackson, W.; Thompson, M.; Rios, A. C.; Yeung,
   K.; Dateo, C.
Bibcode: 2022LPICo2678.2843C
Altcode:
  Did early solar system photo-magnetic forces create enantiomer excesses
  in organic compounds?

Title: Outgassing Experiments on Carbonaceous Chondrites and Their
    Implications for Titan's Secondary Atmosphere
Authors: Duncan, T.; Yu, X.; Thompson, M.; Kim, K.; Telus, M.; Joshi,
   T.; Lederman, D.
Bibcode: 2021LPI....52.2664D
Altcode:
  Outgassed organics / Inside Titan / May resupply / The mysterious
  methane.

Title: Pre-Flight Calibration of the Mars 2020 Rover Mastcam Zoom
    (Mastcam-Z) Multispectral, Stereoscopic Imager
Authors: Hayes, Alexander G.; Corlies, P.; Tate, C.; Barrington,
   M.; Bell, J. F.; Maki, J. N.; Caplinger, M.; Ravine, M.; Kinch,
   K. M.; Herkenhoff, K.; Horgan, B.; Johnson, J.; Lemmon, M.; Paar,
   G.; Rice, M. S.; Jensen, E.; Kubacki, T. M.; Cloutis, E.; Deen, R.;
   Ehlmann, B. L.; Lakdawalla, E.; Sullivan, R.; Winhold, A.; Parkinson,
   A.; Bailey, Z.; van Beek, J.; Caballo-Perucha, P.; Cisneros, E.;
   Dixon, D.; Donaldson, C.; Jensen, O. B.; Kuik, J.; Lapo, K.; Magee,
   A.; Merusi, M.; Mollerup, J.; Scudder, N.; Seeger, C.; Stanish, E.;
   Starr, M.; Thompson, M.; Turenne, N.; Winchell, K.
Bibcode: 2021SSRv..217...29H
Altcode:
  The NASA Perseverance rover Mast Camera Zoom (Mastcam-Z) system is a
  pair of zoomable, focusable, multi-spectral, and color charge-coupled
  device (CCD) cameras mounted on top of a 1.7 m Remote Sensing Mast,
  along with associated electronics and two calibration targets. The
  cameras contain identical optical assemblies that can range in focal
  length from 26 mm (25.5<SUP>∘</SUP>×19.1<SUP>∘</SUP>FOV ) to 110
  mm (6.2<SUP>∘</SUP>×4.2<SUP>∘</SUP>FOV ) and will acquire data
  at pixel scales of 148-540 μm at a range of 2 m and 7.4-27 cm at 1
  km. The cameras are mounted on the rover's mast with a stereo baseline
  of 24.3 ±0.1 cm and a toe-in angle of 1.17 ±0.03<SUP>∘</SUP>
  (per camera). Each camera uses a Kodak KAI-2020 CCD with 1600 ×1200
  active pixels and an 8 position filter wheel that contains an IR-cutoff
  filter for color imaging through the detectors' Bayer-pattern filters, a
  neutral density (ND) solar filter for imaging the sun, and 6 narrow-band
  geology filters (16 total filters). An associated Digital Electronics
  Assembly provides command data interfaces to the rover, 11-to-8 bit
  companding, and JPEG compression capabilities. Herein, we describe
  pre-flight calibration of the Mastcam-Z instrument and characterize
  its radiometric and geometric behavior. Between April 26t<SUP>h</SUP>
  and May 9t<SUP>h</SUP>, 2019, ∼45,000 images were acquired during
  stand-alone calibration at Malin Space Science Systems (MSSS) in San
  Diego, CA. Additional data were acquired during Assembly Test and Launch
  Operations (ATLO) at the Jet Propulsion Laboratory and Kennedy Space
  Center. Results of the radiometric calibration validate a 5% absolute
  radiometric accuracy when using camera state parameters investigated
  during testing. When observing using camera state parameters not
  interrogated during calibration (e.g., non-canonical zoom positions),
  we conservatively estimate the absolute uncertainty to be &lt;10 %
  . Image quality, measured via the amplitude of the Modulation Transfer
  Function (MTF) at Nyquist sampling (0.35 line pairs per pixel),
  shows MTF<SUB>Nyquist</SUB>=0.26 -0.50 across all zoom, focus, and
  filter positions, exceeding the &gt;0.2 design requirement. We discuss
  lessons learned from calibration and suggest tactical strategies that
  will optimize the quality of science data acquired during operation
  at Mars. While most results matched expectations, some surprises were
  discovered, such as a strong wavelength and temperature dependence on
  the radiometric coefficients and a scene-dependent dynamic component
  to the zero-exposure bias frames. Calibration results and derived
  accuracies were validated using a Geoboard target consisting of
  well-characterized geologic samples.

Title: Methane: the Ideal Biosignature for the JWST Era?
Authors: Thompson, M.; Krissansen-Totton, J.; Fortney, J.
Bibcode: 2021BAAS...53c1024T
Altcode:
  The next phase of exoplanet science will focus on characterizing
  exoplanet atmospheres, including those of low-mass, terrestrial
  planets. A comprehensive understanding of possible biosignatures
  that may be detected with the next generation of ground and space
  telescopes is warranted. While some biosignature gases, such as
  oxygen and phosphine, have recently been reviewed in depth (Meadows et
  al. 2018 and Sousa-Silva et al. 2020), these will likely be extremely
  difficult to detect with JWST. In contrast, while it has not been
  thoroughly reviewed, methane at Earth-like biogenic fluxes is one
  of the only biosignatures that may be readily detectable with JWST
  (Krissansen-Totton et al. 2018a). In fact, an early Earth-like,
  methane-rich atmosphere would be easier to detect with JWST than
  modern Earth's oxygen-rich atmosphere (ibid). Here we present our
  preliminary work on a comprehensive review of methane biosignatures
  and false positives. Biogenic methane production, or methanogenesis,
  is a simpler metabolism than oxygenic photosynthesis, that is carried
  out by anaerobic microbes (i.e., those not requiring oxygen for
  growth). Methanogens use either CO2 and H2 or acetate as substrates
  (Schwieterman et al. 2018). This process could be widespread due to
  the likely ubiquity of the CO2+H2 redox couple in terrestrial planet
  atmospheres, and the antiquity of methanogenesis on Earth (Wolfe
  and Fournier 2018). We briefly review the current understanding of
  the origin and evolution of methanogens, the organisms responsible
  for methanogenesis, and how this process relates to origins-of-life
  theories. When CH4 is invoked as a possible biosignature it is
  often included with a strongly oxidizing companion gas (e.g., CO2 or
  O2/O3). This is because it is difficult to explain abundant CH4 if
  a terrestrial planet atmosphere's redox state is more oxidizing so
  that the thermodynamically stable form of carbon would not be CH4
  (Schwieterman et al. 2018). However, even in atmospheres devoid
  of oxygen, CH4 has a short photochemical lifetime on habitable
  zone rocky planets, and the large fluxes required to sustain high
  CH4 abundances are likely much greater than could be supplied by
  abiotic processes (e.g., magmatic outgassing, serpentinization)
  (Krissansen-Totton et al. 2018b, Wogan et al. 2020). In addition,
  many abiotic, geological processes that produce CH4 are expected to
  also produce abundant CO, which life readily consumes, so the presence
  of CH4 and CO2 but absence of CO strengthens the case for biogenicity
  (Krissansen-Totton et al. 2018b). Although CH4+CO2 (minus CO) might
  coexist in thermodynamic equilibrium on planets without large surface
  oceans (Woitke et al. 2020), in practice, such atmospheres would be
  photochemically unstable and, in particular, the CH4 would have a short
  lifetime (less than ~1 Myrs). In addition to briefly discussing methane
  on Mars and Titan, we review the presence of methane in Jovian and
  sub-Neptune planet atmospheres. In many giant planets, methane is the
  most abundant carbon-bearing gas and can be replenished indefinitely
  because, although methane is photodissociated in the upper atmosphere,
  hydrogen is never depleted and carbon and hydrogen can recombine
  deeper in the atmosphere where temperatures and pressures are high
  enough for methane production to be thermodynamically favorable and
  kinetically viable (Moses et al. 2013). On the other hand, terrestrial
  planets with high mean molecular weight atmospheres do not have
  deep enough atmospheres to replenish methane without an additional
  source (abiotic or biotic). In terrestrial atmospheres without a
  replenishment source, methane is photodissociated and hydrogen is
  lost to space on short timescales (~10s of thousands of years for ~1
  bar atmospheres). For planets in the sub-Neptune regime, we seek to
  determine how much atmosphere is necessary for a planet to sustain
  methane via thermodynamic recombination against photodissociation. In
  summary, for terrestrial planets to have methane-rich atmospheres,
  the methane must be constantly replenished. We explore to what extent
  abiotic CH4 replenishment is possible based on prior work on abiotic
  methane sources including water-rock reactions, volcanic outgassing,
  and impacts (e.g., Etiope &amp; Lollar 2013, Wogan et al. 2020, Kress
  &amp; McKay 2003). We review methane false positives on terrestrial
  planets and determine if they are likely to produce methane fluxes
  as large as those caused by known biogenic sources. Through this
  comprehensive review, we will develop a framework for identifying
  methane biosignatures and discuss detectability prospects with JWST.

Title: VizieR Online Data Catalog: PGCCs in lambda Orionis
    complex. II. Cores at 850um (Yi+, 2018)
Authors: Yi, H. -W.; Lee, J. -E.; Liu, T.; Kim, K. -T.; Choi, M.;
   Eden, D.; Evans, N. J., II; di, Francesco J.; Fuller, G.; Hirano,
   N.; Juvela, M.; Kang, S. -J.; Kim, G.; Koch, P. M.; Lee, C. W.;
   Li, Di; Liu, H. -Y. B.; Liu, H. -L.; Liu, S. -Y.; Rawlings, M. G.;
   Ristorcelli, I.; Sanhueza, P.; Soam, A.; Tatematsu, K.; Thompson,
   M.; Toth, L. V.; Wang, Ke; White, G. J.; Wu, Y.; Yang, Y. -L.
Bibcode: 2021yCat..22360051Y
Altcode:
  As part of the legacy survey, "SCUBA-2 Continuum Observations of
  Pre-protostellar Evolution" (SCOPE; Liu+ 2018ApJS..234...28L and Eden+
  2019MNRAS.485.2895E ; proposal code: M16AL003), we observed 58 Planck
  Galactic Cold Clumps (PGCCs) in the "CV Daisy" mapping mode, which
  is suitable for small and compact sources with sizes of less than 3'
  at 450 and 850um with the Submillimetre Common-User Bolometer Array 2
  (SCUBA-2) at the 15m James Clerk Maxwell Telescope (JCMT). <P />We also
  included archival data of 38 PGCCs located in the Orion A and B clouds
  from the JCMT Science Archive hosted by the Canadian Astronomical Data
  Centre (CADC). <P />Table 1 lists information about the 96 PGCCs. <P
  />We also included data from the Wide-Field Infrared Survey Explorer
  (WISE) AllWISE catalog (Wright+ 2010, see II/328). <P />Finally, we
  obtained 119 cores within the 40 detected PGCCs in the Orion complex. In
  the λ Orionis cloud, there are 8 detected PGCCs, from which 15 cores
  are identified. The Orion A cloud has 74 cores in 23 PGCCs, and the
  Orion B cloud has 30 cores in 9 PGCCs. The list of cores in each cloud
  is found in Tables 2-4. <P />(4 data files).

Title: Outgassing Experiments on Carbonaceous Chondrites to Understand
    the Formation of Titan's Atmosphere
Authors: Duncan, T.; Yu, X.; Thompson, M.; Kim, K.
Bibcode: 2020AGUFMP071...08D
Altcode:
  Titan is the only known moon in the Solar System with a substantial
  atmosphere of N 2 and CH 4 , however, its origin and evolution
  are not well understood. Titan's present amount of atmospheric
  CH 4 was predicted to be destroyed photochemically on very short
  timescales compared to the age of the Solar System suggesting a
  resupply mechanism is necessary [1]. Cassini provided new insight
  into the origin of Titan's atmosphere by measuring abundances of
  primordial noble gases and found that instead of being incorporated
  during formation, Titan's atmosphere is likely linked to its interior
  [2][3]. Recent theoretical modeling of Titan's atmosphere and interior
  [4][5] suggests that its atmosphere could have originated in part by
  outgassing of primordial organics in its interior. Insoluble organic
  matter (IOM) found in carbonaceous chondrites may serve as an analog
  for the organic material in Titan's interior and provide experimental
  constraints on the outgassed component of its atmosphere. Therefore,
  outgassing experiments on carbonaceous chondrites can help inform how
  Titan obtained its secondary atmosphere, and in particular reveal a
  possible source for Titan's atmospheric CH 4 . By heating primitive
  meteorite samples and measuring the abundances of their released
  volatiles, we may be able to connect what we see in the lab to species
  in Titan's atmosphere today. In this study, we use samples of Murchison,
  a CM carbonaceous chondrite, which contains substantial amounts of
  insoluble organic matter (IOM).We heated 3 mg of powdered (20-100 µm
  and &lt;20 µm) Murchison samples from room temperature to 1200° C
  in a furnace and continuously monitored 10 outgassed volatile species
  with a Residual Gas Analyzer (RGA). We plan to conduct additional
  experiments with other primitive meteorites and their extracted IOM to
  further investigate the link between outgassing of primitive materials
  and the origin of Titan's atmosphere. <P />Yung, Y. L., et al. 1984 ,
  Astrophys. J. , 55, 465 <P />Niemann, H. B., et al. 2005, Nature, 438,
  779 <P />Niemann, H. B., et al. 2010, J. Geophys. Res. , 115, 65 <P
  />Miller, K. E., .et al. 2019, Astrophys. J. , 871, 59 <P />Neri, A.,
  et al. 2019, Earth Planet. Sci. Letts , 530, 6

Title: Carbonaceous Chondrite Outgassing Experiments to Constrain
    the Formation of Titan's Atmosphere
Authors: Kim, K.; Thompson, M.; Yu, X.; Duncan, T.; Telus, M.; Joshi,
   T.; Lederman, D.
Bibcode: 2020DPS....5221803K
Altcode:
  The origin of Titan's thick N<SUB>2</SUB> and CH<SUB>4</SUB> dominated
  atmosphere is an outstanding puzzle in planetary science. Photochemical
  models predict that Titan's current atmospheric methane would be
  quickly destroyed by photolysis in ~30 million years [1], suggesting
  a possible need for a mechanism to replenish the methane [2]. One
  potential mechanism has been linked to the interior composition and
  structure of Titan, and to better understand this question of methane
  persistence in the atmosphere, we turn to Titan's atmospheric formation
  [3]. Titan's atmosphere may have been produced in part from interior
  outgassing with evidence coming from the detection of outgassed
  <SUP>40</SUP>Ar, a radiogenic decay product of <SUP>40</SUP>K, that
  was detected by the Huygens Gas Chromatograph and Mass Spectrometer
  [4]. Recent studies suggest that organic material similar to the
  refractory organics found in comets may be a necessary component
  of Titan's interior, and outgassing of such material could provide
  significant amounts of N<SUB>2</SUB> and CH<SUB>4</SUB> to replenish
  Titan's atmosphere [5][6]. For this study, we analyze carbonaceous
  (CM) chondrites because they contain insoluble organic matter (IOM),
  which is similar to cometary refractory organics and may serve as an
  analog to part of the interior material of Titan. In particular, we
  studied samples from the Murchison meteorite because it is a pristine
  CM carbonaceous chondrite fall with a significant IOM component. We
  performed a suite of stepped heating experiments that will help place
  experimental constraints on the amounts of outgassed carbon and nitrogen
  compounds from CM chondrites to help inform the outgassed origin and
  composition of Titan's atmosphere. We performed these experiments on
  powdered Murchison samples with two grain size distributions, one
  including grains between 20-100 microns in diameter and the other
  with grain diameters &lt;20 microns. We present the results of our
  stepped heating experiments in which we heated these powdered samples
  up to 1200 C in a furnace connected to a residual gas analyzer (RGA)
  that continuously monitored the partial pressures of 10 different
  outgassed species (e.g., C, CO, CO<SUB>2</SUB>, CH<SUB>4</SUB>, N,
  N<SUB>2</SUB>). By measuring the abundances of outgassed volatiles, we
  compare our results to prior experimental work on IOM from carbonaceous
  chondrites and discuss how these experiments will inform the outgassing
  origin and composition of Titan's atmosphere. <P />1: Yung, Y. L.,
  et al. 1984. ApJ., 55. ; 2: Hörst, S. M. 2017. J. Gphys Res., 122. ;
  3: Nixon, C., et al, 2018. Pl. Sp. Sci., 155. ; 4: Niemann, H.B.,
  et al. 2005. Nat. 438. ; 5: Miller, K. E., et al. 2019. ApJ., 871. ;
  6: Néri, A., et al. 2019. E. Pl. Sci Lts, 530.

Title: VizieR Online Data Catalog: Abundances of Gaia DR2 wide
    binaries (Hawkins+, 2020)
Authors: Hawkins, K.; Lucey, M.; Ting, Y. -S.; Ji, A.; Katzberg, D.;
   Thompson, M.; El-Badry, K.; Teske, J.; Nelson, T.; Carrillo, A.
Bibcode: 2020yCat..74921164H
Altcode:
  Stellar parameters and abundances for 50 stars in 25 wide binaries
  observed with McDonald Observatory in 2019. <P />(3 data files).

Title: VizieR Online Data Catalog: SCUBA-2 Ambitious Sky Survey
    (Nettke+, 2017)
Authors: Nettke, W.; Scott, D.; Gibb, A. G.; Thompson, M.;
   Chrysostomou, A.; Evans, A.; Hill, T.; Jenness, T.; Joncas, G.; Moore,
   T.; Serjeant, S.; Urquhart, J.; Vaccari, M.; Weferling, B.; White,
   G.; Zhu, M.
Bibcode: 2020yCat..74680250N
Altcode:
  This beam-sized source catalogue is based on scans of Scuba-2 imagery
  obtained between 2012 May 15 and 2014 May 12 using the James Clerk
  Maxwell Telescope. There are three catalogues as well as one PDF file
  which details a source comparison of samples from each catalogue. <P
  />(4 data files).

Title: Assessing the Threat of Major Outbreaks of Vector-Borne
    Diseases Under a Changing Climate
Authors: Thompson, R. N.; Thompson, M. J.; Hurrell, J. W.; Sun, L.;
   Obolski, U.
Bibcode: 2020ASSP...57...25T
Altcode:
  Michael J. Thompson served as the Director of the High Altitude
  Observatory at the National Center for Atmospheric Research (NCAR) in
  Boulder, Colorado, where he was also a Senior Scientist. In September
  2013, Michael became the Deputy Director and Chief Operating Officer
  of NCAR, enjoying a very close working relationship with Director Jim
  Hurrell. During this time, Michael oversaw an organisation conducting
  research in a range of fields, including his own topics of solar and
  stellar physics, as well as others such as atmospheric chemistry and
  climate science. At the same time, his son Robin was completing a PhD
  in mathematical epidemiology at the University of Cambridge, UK, after
  which he was awarded an independent Junior Research Fellowship at the
  University of Oxford. However, the work conducted at NCAR and Robin's
  research have more overlap than might at first be expected. Here
  we present results from a collaboration that was set up following
  Michael's untimely death in October 2018, between climate scientists
  (Jim Hurrell and Lantao Sun) and mathematical epidemiologists (Robin
  Thompson and Uri Obolski). Specifically, we propose a framework for
  studying the effect of climate variability and change on vector-borne
  disease risk. We introduce a new quantity—the Instantaneous Outbreak
  Risk (IOR)—which quantifies the risk posed by an invading pathogen
  accounting for the climatic conditions when that pathogen enters the
  population. We show how the IOR can be used to assess the threat from
  vector-borne diseases under a changing climate.

Title: The Impact of a Fossil Magnetic Field on Dipolar Mixed-Mode
    Frequencies in Sub- and Red-Giant Stars
Authors: Bugnet, L.; Prat, V.; Mathis, S.; García, R. A.; Mathur,
   S.; Augustson, K.; Neiner, C.; Thompson, M. J.
Bibcode: 2020ASSP...57..251B
Altcode: 2020arXiv201208684B
  The recent discovery of low-amplitude dipolar oscillation mixed modes in
  massive red giants indicates the presence of a missing physical process
  inside their cores. Stars more massive than ∼ 1.3 M<SUB>⊙</SUB>
  are known to develop a convective core during the main-sequence:
  the dynamo process triggered by this convection could be the origin
  of a strong magnetic field inside the core of the star, trapped when
  it becomes stably stratified and for the rest of its evolution. The
  presence of highly magnetized white dwarfs strengthens the hypothesis
  of buried fossil magnetic fields inside the core of evolved low-mass
  stars. If such a fossil field exists, it should affect the mixed
  modes of red giants as they are sensitive to processes affecting
  the deepest layers of these stars. The impact of a magnetic field
  on dipolar oscillations modes was one of Pr. Michael J. Thompson's
  research topics during the 90s when preparing the helioseismic SoHO
  space mission. As the detection of gravity modes in the Sun is still
  controversial, the investigation of the solar oscillation modes did
  not provide any hint of the existence of a magnetic field in the solar
  radiative core. Today we have access to the core of evolved stars thanks
  to the asteroseismic observation of mixed modes from CoRoT, Kepler,
  K2 and TESS missions. The idea of applying and generalizing the work
  done for the Sun came from discussions with Pr. Michael Thompson in
  early 2018 before we lost him. Following the path we drew together,
  we theoretically investigate the effect of a stable axisymmetric mixed
  poloidal and toroidal magnetic field, aligned with the rotation axis of
  the star, on the mixed modes frequencies of a typical evolved low-mass
  star. This enables us to estimate the magnetic perturbations to the
  eigenfrequencies of mixed dipolar modes, depending on the magnetic
  field strength and the evolutionary state of the star. We conclude
  that strong magnetic fields of ∼ 1MG should perturb the mixed-mode
  frequency pattern enough for its effects to be detectable inside
  current asteroseismic data.

Title: On the Limits of Seismic Inversions for Radial Differential
    Rotation of Solar-Type Stars
Authors: Santos, Ângela R. G.; Mathur, Savita; García, Rafael A.;
   Thompson, Michael J.
Bibcode: 2020ASSP...57..269S
Altcode:
  Seismic data contains information on stellar internal rotation, which
  plays an important role on dynamo models. Due to the uncertainties
  on the observations and stellar models, determining internal rotation
  of main-sequence solar-type stars has been challenging. Here, we use
  artificial rotational splittings for two-zone profiles to explore the
  limitations to constrain internal rotation profiles.

Title: Meteorite Outgassing Experiments to Inform Chemical Abundances
    of Super-Earth Atmospheres
Authors: Thompson, M.; Fortney, J. J.; Telus, M.; Lederman, D.;
   Joshi, T.
Bibcode: 2019AGUFM.P23B3487T
Altcode:
  At present, there is no first­ principles understanding of how to
  connect a terrestrial planet's bulk composition to its atmospheric
  properties. Since terrestrial exoplanets likely form their atmospheres
  through degassing (Elkins­-Tanton &amp; Seager 2008), a logical first
  step to build such a theory for super­Earths is to assay meteorites,
  the left­over building blocks of planets, by heating them to measure
  the outgassed volatiles. Our Solar System presents a wide variety of
  meteorite types, including chondrites which are primitive unaltered
  rocks believed to be representative of the material that formed
  the rocky planets. We present the current results of our meteorite
  outgassing experiments in which we heated a variety of chondritic
  meteorite samples, at carefully controlled rates to temperatures
  from 200 to 1200 °C and measured the partial pressures and relative
  abundances of the outgassed volatile species (e.g., CO2, H2O, CH4, H2,
  O2, S, Na) as a function of temperature and time. Our experimental
  set­up consisted of a residual gas analyzer connected to a furnace
  to heat samples at specified rates. We compare the results of these
  experiments to Schaefer and Fegley's prior theoretical chemical
  equilibrium and kinetics calculations which modeled thermal outgassing
  for a wide variety of chondrites to predict the composition of
  terrestrial atmospheres formed via outgassing of specific types of
  meteorites (Schaefer &amp; Fegley 2007, Schaefer &amp; Fegley 2010). In
  addition to testing and validating Schaefer and Fegley's models,
  the results from our experiments inform the phase space of chemical
  abundances used in atmospheric models of super­Earth exoplanets.

Title: Overview of the Search for Space Weathering Signals on the
Surface of Bennu: One Rock Type, or Two?
Authors: Clark, B. E.; Ferrone, S. M.; Kaplan, H. H.; Zou, X. -D.;
   Trang, D.; DellaGiustina, D. N.; LeCorre, L.; Golish, D. R.; Li,
   J. -Y.; Ballouz, R. -L.; Hergenrother, C. W.; Rizk, B.; Burke, K. N.;
   Bennett, C. A.; Keller, L.; Howell, E. S.; Lantz, C.; Barucci, M. A.;
   Fornasier, S.; Thompson, M.; Michel, P.; Molaro, J.; Jawin, E. R.;
   Delbo, M.; Simon, A.; Reuter, D.; Pajola, M.; Lauretta, D. S.
Bibcode: 2019LPICo2189.2125C
Altcode:
  We provide an overview of the evidence for space weathering on asteroid
  (101955) Bennu, and summarize relevant findings from several ongoing
  parallel studies of surface processes and surface properties.

Title: Lightcurve Analysis and Rotation Period of 6372 Walker
Authors: Hayes-Gehrke, Melissa N.; Berk, Marley; Fatodu, Abisola;
   Kanani, Bhargin; Kropschot, Quinn; Marks, Julia; Misangyi, Ella;
   Nguyen, Matthew; Stone, Julie; Suniga, Joshua; Thompson, Michael;
   Vorsteg, Matthew; Wagman, Timothy; Marchini, Alessandro; Banfi,
   Massimo; Papini, Riccardo; Salvaggio, Fabio; Brincat, Stephen M.;
   Galdies, Charles; Winston Grech
Bibcode: 2019MPBu...46..388H
Altcode:
  From 2019 March-May, images of minor planet 6372 Walker were captured
  to investigate its rotation period. Our analysis found a period of
  44.25 ±0.01 h.

Title: VizieR Online Data Catalog: Radio observations of G074.11+00.11
    (Saajasto+, 2019)
Authors: Saajasto, M.; Harju, J.; Juvela, M.; Tie, L.; Zhang, Q.;
   Liu, S. -Y.; Hirano, N.; Wu, Y.; Kim, K. -T.; Tatematsu, K.; Wang,
   K.; Thompson, M.
Bibcode: 2019yCat..36300069S
Altcode:
  This catalogue contains the radio observations of a cold clump
  G074.11+00.11. The catalogue contains all of the observed molecular
  lines, however, please note that not all of the observed molecules
  were detected. The included data has been obtained from several
  telescopes: Purple Mountain Observatory (PMO), Korean Very Long Baseline
  Interferometry Network (KVN), the Submillimeter Telescope (SMT), and
  the Submillimeter Array (SMA). For a more detailed description of the
  data, velocity resolutions etc. please see the Section 2, Observations
  of the main paper and the references therein. <P />(24 data files).

Title: Space Weathering of Carbonaceous Asteroids and Meteorites
Authors: Loeffler, M. J.; Thompson, M.; Keller, L. P.
Bibcode: 2018AGUFM.P21D3381L
Altcode:
  It is well known that solar wind particles and micrometeorite impacts
  alter the surface regolith of airless bodies, such as the Moon and
  asteroids. On the scale of the regolith grains, these alterations
  are manifested through physical and chemical changes of the outer
  layers, which can be due to a combination of direct irradiation or
  redeposition of material evaporated during irradiation. Laboratory
  studies focusing on simulating lunar- and asteroid-type space weathering
  in iron-bearing minerals have been relatively successful at showing
  that much of the changes in optical properties (spectral reddening
  and darkening in the visible-near-infrared region) are driven by the
  formation of chemically reduced iron produced through either solar wind
  bombardment or micrometeorite impacts. However, a similar correlation
  has not yet been made for carbonaceous asteroids and meteorites, as
  laboratory experiments have shown a variety of trends, suggesting that
  weathering in these types of minerals may be more complicated. Thus, we
  have begun a systematic study where we are looking at space weathering
  in diagnostic minerals found in carbonaceous asteroids and meteorites,
  focusing on how the optical, structural and chemical properties of these
  minerals' components are altered by ion and laser irradiation. Here we
  present some of our most recent results on effects that micrometeorite
  impacts, simulated with a pulsed laser, has on sulfide minerals, using
  the our new ultra-high vacuum system at Northern Arizona University.

Title: Solar Physics from Unconventional Viewpoints
Authors: Gibson, Sarah E.; Vourlidas, Angelos; Hassler, Donald M.;
   Rachmeler, Laurel A.; Thompson, Michael J.; Newmark, Jeffrey; Velli,
   Marco; Title, Alan; McIntosh, Scott W.
Bibcode: 2018FrASS...5...32G
Altcode: 2018arXiv180509452G
  We explore new opportunities for solar physics that could be realized
  by future missions providing sustained observations from vantage
  points away from the Sun-Earth line. These include observations from
  the far side of the Sun, at high latitudes including over the solar
  poles, or from near-quadrature angles relative to the Earth (e.g.,
  the Sun-Earth L4 and L5 Lagrangian points). Such observations fill
  known holes in our scientific understanding of the three-dimensional,
  time-evolving Sun and heliosphere, and have the potential to open new
  frontiers through discoveries enabled by novel viewpoints.

Title: The Coronal Solar Magnetism Observatory
Authors: Thompson, Michael J.; Tomczyk, Steven; Gibson, Sarah E.;
   McIntosh, Scott W.; Landi, Enrico
Bibcode: 2018IAUS..335..359T
Altcode:
  The Coronal Solar Magnetism Observatory (CoSMO) is a proposed new
  facility led by the High Altitude Observatory and a consortium of
  partners to measure magnetic field and plasma properties in a large
  (one degree) field of view extending down to the inner parts of the
  solar corona. CoSMO is intended as a research facility that will
  advance the understanding and prediction of space weather. The
  instrumentation elements of CoSMO are: a white-light coronagraph
  (KCor), already operational at the Mauna Loa Solar Observatory
  (MLSO); the Chromosphere and Prominence Magnetometer (ChroMag), due
  for deployment to MLSO next year; and the CoSMO Large Coronagraph (LC)
  which has completed Preliminary Design Review.

Title: Design of a next generation synoptic solar observing network:
    solar physics research integrated network group (SPRING)
Authors: Gosain, Sanjay; Roth, Markus; Hill, Frank; Pevtsov, Alexei;
   Martinez Pillet, Valentin; Thompson, Michael J.
Bibcode: 2018SPIE10702E..4HG
Altcode:
  Long-term synoptic observations of the Sun in different wavelength
  regions are essential to understand its secular behavior. Such
  observations have proven very important for discovery of 11 year
  solar activity cycle, 22 year magnetic cycle, polar field reversals,
  Hale's polarity law, Joy's law, that helped Babcock and Leighton
  to propose famous solar dynamo model. In more recent decades, the
  societal impact of the secular changes in Sun's output has been felt in
  terms of solar inputs to terrestrial climate-change and space-weather
  hazards. Further, it has been realized that to better understand the
  activity phenomena such as flares and coronal mass ejections (CMEs)
  one needs synoptic observations in multiple spectral lines to enable
  tomographic inference of physical parameters. Currently, there are
  both space and ground based synoptic observatories. However, given
  the requirements for the long-term stability and reliability of such
  synoptic datasets, ground-based facilities are more preferable. Also,
  the ground based observatories are easy to maintain or upgrade while
  detailed and frequent calibrations are easily possible. The only
  ground-based facility that currently provides full-disk velocity and
  magnetic field maps of the Sun around the clock and at good cadence,
  is the Global Oscillations Network Group (GONG) network of National
  Solar Observatory (NSO) which is operational since the mid 90s. Due
  to its aging instrumentation, operating for nearly three decades, and
  new requirements to obtain multiwavelength observations, a need is felt
  in the solar community to build a next generation synoptic observatory
  network. A group of international observatories have come together under
  the auspices of SOLARNET program, funded by European Union (EU), to
  carryout a preliminary design study of such a synoptic solar observing
  facility called "SPRING", which stands for Solar Physics Research
  Integrated Network Group. In this article we will present concept of
  SPRING and the optical design concept of its major instruments.ts.

Title: Signatures of Solar Cycle 25 in Subsurface Zonal Flows
Authors: Howe, R.; Hill, F.; Komm, R.; Chaplin, W. J.; Elsworth, Y.;
   Davies, G. R.; Schou, J.; Thompson, M. J.
Bibcode: 2018ApJ...862L...5H
Altcode: 2018arXiv180702398H
  The pattern of migrating zonal flow bands associated with the solar
  cycle, known as the torsional oscillation, has been monitored with
  continuous global helioseismic observations by the Global Oscillations
  Network Group (GONG), together with those made by the Michelson
  Doppler Imager (MDI) on board the Solar and Heliospheric Observatory
  (SOHO) and its successor, the Helioseismic and Magnetic Imager (HMI)
  on board the Solar Dynamics Observatory (SDO), since 1995, giving us
  nearly two full solar cycles of observations. We report that the flows
  now show traces of the mid-latitude acceleration that is expected to
  become the main equatorward-moving branch of the zonal flow pattern for
  Cycle 25. Based on the current position of this branch, we speculate
  that the onset of widespread activity for Cycle 25 is unlikely to be
  earlier than the middle of 2019.

Title: Solar Observations Away from the Sun-Earth Line
Authors: Gibson, Sarah E.; McIntosh, Scott William; Rachmeler,
   Laurel; Thompson, Michael J.; Title, Alan M.; Velli, Marco C. M.;
   Vourlidas, Angelos
Bibcode: 2018tess.conf40340G
Altcode:
  Observations from satellite missions have transformed the field of solar
  physics. High-resolution observations with near-continuous temporal
  coverage have greatly extended our capability for studying long-term
  and transient phenomena, and the opening of new regions of the solar
  spectrum has made detailed investigation of the solar atmosphere
  possible. <P />However, to date most solar space-based missions
  have been restricted to an observational vantage in the vicinity of
  the Sun-Earth line, either in orbit around the Earth or from the L1
  Lagrangian point. As a result, observations from these satellites
  represent the same geometrical view of the Sun that is accessible
  from the Earth. <P />Understanding the deep interior structure of the
  Sun and the full development of solar activity would really benefit
  from fully three-dimensional monitoring of the solar atmosphere and
  heliosphere. On the one hand, simultaneous spacecraft observations
  from multiple vantage points would allow studies of the deep interior
  structure of the sun via stereoscopic helioseismology; on the other,
  distributed observations would allow the understanding of the complete
  evolution of activity complexes and enhance space weather predictions
  dramatically. <P />Presently, observations of the Sun away from Earth
  are obtained by the STEREO pair of satellites, which have provided
  an unprecedented global view by orbiting around to the far side of
  the Sun, and the Ulysses mission, which achieved a high-inclination
  (80˚) near-polar orbit (but which, however, did not include any solar
  imaging instruments). The forthcoming Solar Orbiter mission, which
  will orbit the sun and reach a maximum inclination of 34˚ out of the
  ecliptic should provide the first detailed mapping of the sun's polar
  fields. In addition, Solar Probe Plus will explore the outer corona
  and inner Heliosphere with very rapid solar encounters at a minimum
  perihelion 9.86 solar radii from the center of the Sun. <P />We explore
  some of the new opportunities for solar physics that can be realized
  by future missions that provide sustained observations from vantage
  points away from the Sun-Earth line (and in some cases the ecliptic
  plane): observations from the far side of the Sun, over its poles,
  or from the L5 Lagrangian point.

Title: Flyby and Impact of Chariklo: A New Frontiers Class Centaur
    Reconnaissance Mission Concept from the 2017 NASA-JPL Planetary
    Science Summer Seminar
Authors: Bouchard, M. C.; Howell, S. M.; Chou, L.; Thompson, M.;
   Cusson, S.; Marcus, M.; Brodsky Smith, H.; Bhattaru, S.; Balock,
   J. J.; Brueshaber, S.; Eggl, S.; Jawin, E. R.; Miller, K. E.; Rizzo,
   M.; Steakley, K.; Thomas, N. H.; Trent, K.; Ugelow, M.; Budney, C. J.;
   Mitchell, K. L.
Bibcode: 2018LPI....49.2087B
Altcode:
  This abstract summarizes a New Frontiers mission concept to the Centaur
  Chariklo that was created during the 2017 NASA/JPL Planetary Science
  Summer Seminar.

Title: Solar Magnetic Fields
Authors: Balogh, André; Cliver, Edward; Petrie, Gordon; Solanki,
   Sami; Thompson, Michael; von Steiger, Rudolf
Bibcode: 2018smf..book.....B
Altcode:
  No abstract at ADS

Title: The Life Cycle of Active Region Magnetic Fields
Authors: Cheung, M. C. M.; van Driel-Gesztelyi, L.; Martínez Pillet,
   V.; Thompson, M. J.
Bibcode: 2018smf..book..317C
Altcode:
  No abstract at ADS

Title: The Life Cycle of Active Region Magnetic Fields
Authors: Cheung, M. C. M.; van Driel-Gesztelyi, L.; Martínez Pillet,
   V.; Thompson, M. J.
Bibcode: 2017SSRv..210..317C
Altcode: 2016SSRv..tmp...46C
  We present a contemporary view of how solar active region
  magnetic fields are understood to be generated, transported and
  dispersed. Empirical trends of active region properties that guide model
  development are discussed. Physical principles considered important
  for active region evolution are introduced and advances in modeling
  are reviewed.

Title: Prospects and Challenges for Helioseismology
Authors: Toomre, J.; Thompson, M. J.
Bibcode: 2017hdsi.book....7T
Altcode:
  No abstract at ADS

Title: Helioseismology and Dynamics of the Solar Interior
Authors: Thompson, M. J.; Brun, A. S.; Culhane, J. L.; Gizon, L.;
   Roth, M.; Sekii, T.
Bibcode: 2017hdsi.book.....T
Altcode:
  No abstract at ADS

Title: Preface: Helioseismology and Dynamics of the Solar Interior
Authors: Gizon, Laurent; Thompson, Michael J.; Brun, A. Sacha; Culhane,
   J. Len; Roth, Markus; Sekii, Takashi
Bibcode: 2017hdsi.book....1G
Altcode:
  No abstract at ADS

Title: Solar Dynamics, Rotation, Convection and Overshoot
Authors: Hanasoge, S.; Miesch, M. S.; Roth, M.; Schou, J.; Schüssler,
   M.; Thompson, M. J.
Bibcode: 2017hdsi.book...85H
Altcode:
  No abstract at ADS

Title: MeerGAL: the MeerKAT Galactic Plane Survey
Authors: Thompson, M.; Goedhart, S.; Goedhart, S.; Benaglia,
   P.; Beuther, H.; Blomme, R.; Chrysostomou, A. C.; Clark, J. S.;
   Dickinson, C.; Ellingsen, S.; Fenech, D.; Hindson, L.; Longmore,
   S. N.; van Langevelde, H. J.; MacLeod, G.; Molinari, S.; Prinja, R.;
   Purcell, C. R.; Stevens, I.; Umana, G.; Urquhart, J. S.; Vlemmings,
   W.; Walsh, A. J.; Yang, A. Y.; Zijlstra, A.
Bibcode: 2016mks..confE..15T
Altcode: 2016PoS...277E..15T
  No abstract at ADS

Title: Solar Dynamics, Rotation, Convection and Overshoot
Authors: Hanasoge, S.; Miesch, M. S.; Roth, M.; Schou, J.; Schüssler,
   M.; Thompson, M. J.
Bibcode: 2015SSRv..196...79H
Altcode: 2015SSRv..tmp...24H; 2015arXiv150308539H
  We discuss recent observational, theoretical and modeling progress
  made in understanding the Sun's internal dynamics, including its
  rotation, meridional flow, convection and overshoot. Over the past
  few decades, substantial theoretical and observational effort has
  gone into appreciating these aspects of solar dynamics. A review of
  these observations, related helioseismic methodology and inference and
  computational results in relation to these problems is undertaken here.

Title: Prospects and Challenges for Helioseismology
Authors: Toomre, J.; Thompson, M. J.
Bibcode: 2015SSRv..196....1T
Altcode: 2015SSRv..tmp...22T
  Helioseismology has advanced considerably our knowledge of the interior
  of the Sun over the past three decades. Our understanding of the Sun's
  internal structure, its dynamics, rotation, convection and magnetism,
  have all been advanced. Yet there are challenges, areas where the
  results from helioseismology are tantalizing but inconclusive, and
  aspects where the interpretation of the data has still to be put on
  a firm footing. In this paper we shall focus on a number of those
  challenges and give our assessment of where progress needs to be made
  in the next decade.

Title: A helioseismic view of the Sun's internal structure and
    dynamics
Authors: Basu, S.; Thompson, M. J.
Bibcode: 2015exse.book..170B
Altcode:
  No abstract at ADS

Title: Temporal evolution of the solar torsional oscillation and
    implications for cycle 25
Authors: Hill, Frank; Howe, Rachel; Komm, Rudolf; Schou, Jesper;
   Thompson, Michael; Larson, Timothy
Bibcode: 2015TESS....110502H
Altcode:
  The zonal flow known as the torsional oscillation has been observed
  on the Sun’s surface since 1980 and in its interior since 1995. It
  has two branches that migrate during the solar cycle, with one moving
  towards the equator and the other towards the poles. The rate at which
  these branches migrate in latitude is tightly correlated with the
  timing of the solar cycle, as seen during the long minimum between
  cycles 23 and 24. The poleward branch generally becomes visible 10
  to 12 years before the appearance of the magnetic activity associated
  with the corresponding sunspot cycle as it did for the current cycle
  24. However, the poleward flow for cycle 25, which was expected to
  appear in 2008-2010, was not observed. Subsequent analysis showed
  that it is a very weak flow, and is masked by an apparent change
  in the background solar differential rotation rate. We will present
  the latest observations of the zonal flow as determined from global
  helioseismology, and will discuss the implications for the strength
  and timing of cycle 25.

Title: SKA tomography of Galactic star-forming regions and spiral arms
Authors: Loinard, L.; Thompson, M.; Hoare, M.; van Langevelde, H. J.;
   Ellingsen, S.; Brunthaler, A.; Forbrich, J.; Rygl, K.; Rodríguez,
   L. F.; Mioduszewski, A. J.; Torres-López, R. M.; Dzib, S. A.;
   Ortiz-León, G. N.; Bourke, T.; Green, J. A.
Bibcode: 2015aska.confE.166L
Altcode: 2015PoS...215E.166L
  No abstract at ADS

Title: The ionised,radical and molecular Milky Way: spectroscopic
    surveys with the SKA
Authors: Thompson, M.; Beuther, H.; Dickinson, C.; MOttram, J.;
   Klaassen, P.; Ginsburg, A.; Longmore, S.; Remijan, A.; Menten, K. M.
Bibcode: 2015aska.confE.126T
Altcode: 2014arXiv1412.5554T; 2015PoS...215E.126T
  The bandwith, sensitivity and sheer survey speed of the SKA offers
  unique potential for deep spectroscopic surveys of the Milky Way. Within
  the frequency bands available to the SKA lie many transitions that
  trace the ionised, radical and molecular components of the interstellar
  medium and which will revolutionise our understanding of many physical
  processes. In this chapter we describe the impact on our understanding
  of the Milky Way that can be achieved by spectroscopic SKA surveys,
  including "out of the box" early science with radio recombination lines,
  Phase 1 surveys of the molecular ISM using anomalous formaldehyde
  absorption, and full SKA surveys of ammonia inversion lines.

Title: The impact of SKA on Galactic Radioastronomy: continuum
    observations
Authors: Umana, G.; Trigilio, C.; Cerrigone, L.; Cesaroni, R.;
   Zijlstra, A. A.; Hoare, M.; Weis, K.; Beasley, A.; Bomans, D.;
   Hallinan, G.; Molinari, S.; Taylor, R.; Testi, L.; Thompson, M.
Bibcode: 2015aska.confE.118U
Altcode: 2014arXiv1412.5833U; 2015PoS...215E.118U
  The SKA will be a state of the art radiotelescope optimized for both
  large area surveys as well as for deep pointed observations. In this
  paper we analyze the impact that the SKA will have on Galactic studies,
  starting from the immense legacy value of the all-sky survey proposed by
  the continuum SWG but also presenting some areas of Galactic Science
  that particularly benefit from SKA observations both surveys and
  pointed. The planned all-sky survey will be characterized by unique
  spatial resolution, sensitivity and survey speed, providing us with a
  wide-field atlas of the Galactic continuum emission. Synergies with
  existing, current and planned radio Galactic Plane surveys will be
  discussed. SKA will give the opportunity to create a sensitive catalog
  of discrete Galactic radio sources, most of them representing the
  interaction of stars at various stages of their evolution with the
  environment: complete census of all stage of HII regions evolution;
  complete census of late stages of stellar evolution such as PNe and
  SNRs; detection of stellar winds, thermal jets, Symbiotic systems,
  Chemically Peculiar and dMe stars, active binary systems in both
  flaring and quiescent states. Coherent emission events like Cyclotron
  Maser in the magnetospheres of different classes of stars can be
  detected. Pointed, deep observations will allow new insights into the
  physics of the coronae and plasma processes in active stellar systems
  and single stars, enabling the detection of flaring activity in larger
  stellar population for a better comprehension of the mechanism of energy
  release in the atmospheres of stars with different masses and age.

Title: GONG, Helioseismology, and the Sun's internal dynamics
Authors: Thompson, Michael
Bibcode: 2015TESS....121401T
Altcode:
  GONG has made remarkable contributions to the development of
  helioseismology and our understanding of the solar interior. Even
  before GONG produced any data, the teams of community scientists
  formed under the auspices of the GONG project led to significant
  advances in helioseismology, for example the development of helioseismic
  inversion techniques. Once the network became operational and the first
  observations started coming in, GONG data revealed as never before the
  Sun's internal dynamics, in particular the solar internal rotation. In
  this talk I shall review GONG's contribution to helioseismology and
  the helioseismic results from the project.

Title: Very low-luminosity Class I/Flat outflow sources in sigma
Orionis: Clues to alternative formation mechanisms for very low-mass
    stars
Authors: Riaz, Basmah; Whelan, E.; Thompson, M.; Vorobyov, E.;
   Lodieu, N.
Bibcode: 2015AAS...22544907R
Altcode:
  We present an optical through sub-millimetre multi-wavelength study
  of two very low-luminosity Class I/Flat systems, Mayrit 1701117 and
  Mayrit 1082188, in the sigma Orionis cluster. We performed moderate
  resolution (R 1000) optical ( 0.4-0.9mu) spectroscopy with the TWIN
  spectrograph at the Calar Alto 3.5-m telescope. The spectra for both
  sources show prominent emission in accretion- and outflow-associated
  lines. The mean accretion rate measured from multiple line diagnostics
  is 6.4x10^{-10} Msun/yr for Mayrit 1701117, and 2.5x10^{-10} Msun/yr
  for Mayrit 1082188. The outflow mass loss rates for the two systems
  are similar and estimated to be 1x10^{-9} Msun/yr. The activity rates
  are within the range observed for low-mass Class I protostars. We
  obtained sub-millimetre continuum observations with the Submillimetre
  Common-User Bolometer Array (SCUBA-2) bolometer at the James Clerk
  Maxwell Telescope. Both objects are detected at a &gt;5-sigma level
  in the SCUBA-2 850mu band. The bolometric luminosity of the targets as
  measured from the observed spectral energy distribution over 0.8-850mu
  is 0.18+/-0.04 Lsun for Mayrit 1701117, and 0.16+/-0.03 Lsun for Mayrit
  1082188, and is in the very low-mass range. The total dust+gas mass
  derived from sub-millimetre fluxes is 36 M_Jup and 22 M_Jup for Mayrit
  1701117 and Mayrit 1082188, respectively. There is the possibility
  that some of the envelope material might be dissipated by the strong
  outflows driven by these sources, resulting in a final mass of the
  system close to or below the sub-stellar limit. Given the membership
  of these objects in a relatively evolved cluster of 3 Myr of age, we
  consider an alternate formation mechanism in the context of the `hybrid'
  model of disk fragmentation, followed by ejection of a gaseous clump.

Title: The Sun's Interior Structure and Dynamics, and the Solar Cycle
Authors: Broomhall, A. -M.; Chatterjee, P.; Howe, R.; Norton, A. A.;
   Thompson, M. J.
Bibcode: 2015sac..book..191B
Altcode:
  No abstract at ADS

Title: Very low-luminosity Class I/flat outflow sources in σ Orionis
Authors: Riaz, B.; Thompson, M.; Whelan, E. T.; Lodieu, N.
Bibcode: 2015MNRAS.446.2550R
Altcode: 2014arXiv1410.3377R
  We present an optical to submillimetre multiwavelength study of two very
  low-luminosity Class I/flat systems, Mayrit 1701117 and Mayrit 1082188,
  in the σ Orionis cluster. We performed moderate-resolution (R ∼
  1000) optical (∼0.4-0.9 μm) spectroscopy with the Cassegrain Twin
  Spectrograph (TWIN) spectrograph at the Calar Alto 3.5-m telescope. The
  spectra for both sources show prominent emission in accretion-
  and outflow-associated lines. The mean accretion rate measured from
  multiple line diagnostics is 6.4 × 10<SUP>-10</SUP> M<SUB>⊙</SUB>
  yr<SUP>-1</SUP> for Mayrit 1701117 and 2.5 × 10<SUP>-10</SUP>
  M<SUB>⊙</SUB> yr<SUP>-1</SUP> for Mayrit 1082188. The outflow
  mass-loss rates for the two systems are similar and estimated to be
  ∼1 × 10<SUP>-9</SUP> M<SUB>⊙</SUB> yr<SUP>-1</SUP>. The activity
  rates are within the range observed for low-mass Class I protostars. We
  obtained submillimetre continuum observations with the Submillimetre
  Common-User Bolometer Array (SCUBA-2) bolometer at the James Clerk
  Maxwell Telescope. Both objects are detected at a ≥5σ level in
  the SCUBA-2 850-μm band. The bolometric luminosity of the targets as
  measured from the observed spectral energy distribution over ∼0.8-850
  μm is 0.18 ± 0.04 L<SUB>⊙</SUB> for Mayrit 1701117 and 0.16 ±
  0.03 L<SUB>⊙</SUB> for Mayrit 1082188 and is in the very low mass
  range. The total dust+gas mass derived from submillimetre fluxes is
  ∼36 M<SUB>Jup</SUB> and ∼22 M<SUB>Jup</SUB> for Mayrit 1701117
  and Mayrit 1082188, respectively. There is the possibility that some
  of the envelope material might be dissipated by the strong outflows
  driven by these sources, resulting in a final mass of the system close
  to or below the substellar limit.

Title: The Sun's Interior Structure and Dynamics, and the Solar Cycle
Authors: Broomhall, A. -M.; Chatterjee, P.; Howe, R.; Norton, A. A.;
   Thompson, M. J.
Bibcode: 2014SSRv..186..191B
Altcode: 2014arXiv1411.5941B
  The Sun's internal structure and dynamics can be studied with
  helioseismology, which uses the Sun's natural acoustic oscillations
  to build up a profile of the solar interior. We discuss how solar
  acoustic oscillations are affected by the Sun's magnetic field. Careful
  observations of these effects can be inverted to determine the
  variations in the structure and dynamics of the Sun's interior as
  the solar cycle progresses. Observed variations in the structure and
  dynamics can then be used to inform models of the solar dynamo, which
  are crucial to our understanding of how the Sun's magnetic field is
  generated and maintained.

Title: Deciphering Solar Magnetic Activity. I. On the Relationship
    between the Sunspot Cycle and the Evolution of Small Magnetic Features
Authors: McIntosh, Scott W.; Wang, Xin; Leamon, Robert J.; Davey,
   Alisdair R.; Howe, Rachel; Krista, Larisza D.; Malanushenko, Anna V.;
   Markel, Robert S.; Cirtain, Jonathan W.; Gurman, Joseph B.; Pesnell,
   William D.; Thompson, Michael J.
Bibcode: 2014ApJ...792...12M
Altcode: 2014arXiv1403.3071M
  Sunspots are a canonical marker of the Sun's internal magnetic
  field which flips polarity every ~22 yr. The principal variation of
  sunspots, an ~11 yr variation, modulates the amount of the magnetic
  field that pierces the solar surface and drives significant variations
  in our star's radiative, particulate, and eruptive output over that
  period. This paper presents observations from the Solar and Heliospheric
  Observatory and Solar Dynamics Observatory indicating that the 11
  yr sunspot variation is intrinsically tied to the spatio-temporal
  overlap of the activity bands belonging to the 22 yr magnetic activity
  cycle. Using a systematic analysis of ubiquitous coronal brightpoints
  and the magnetic scale on which they appear to form, we show that the
  landmarks of sunspot cycle 23 can be explained by considering the
  evolution and interaction of the overlapping activity bands of the
  longer-scale variability.

Title: A New Ground-Based Network for Synoptic Solar Observations:
    The Solar Physics Research Integrated Network Group (SPRING)
Authors: Hill, Frank; Roth, Markus; Thompson, Michael; Gusain, Sanjay
Bibcode: 2014AAS...22412354H
Altcode:
  SPRING is a project to develop a geographically distributed network
  of instrumentation to obtain synoptic solar observations. Building
  on the demonstrated success of networks to provide nearly-continuous
  long-term data for helioseismology, SPRING will provide data for a wide
  range of solar research areas. Scientific objectives include internal
  solar dynamics and structure; wave transport in the solar atmosphere;
  the evolution of the magnetic field over the activity cycle; irradiance
  fluctuations; and space weather origins. Anticipated data products
  include simultaneous full-disk multi-wavelength Doppler and vector
  magnetic field images; filtergrams in H-Alpha, CaK, and white light;
  and PSPT-type irradiance support. The data will be obtained with a duty
  cycle of around 90% and at a cadence no slower than one minute. The
  current concept is a multi-instrument platform installed in at least
  six locations, and which will also provide context information for
  large-aperture solar telescopes such as EST and the DKIST. There is
  wide support for the idea within the EU and the US solar research
  communities. The project is in the early planning stages, and we are
  open to and looking for participants in the science and instrument
  definition.

Title: Grand Challenges in the Physics of the Sun and Sun-like Stars
Authors: Thompson, Michael
Bibcode: 2014FrASS...1....1T
Altcode: 2014arXiv1406.4228T
  The study of stellar structure and evolution is one of the main
  building blocks of astrophysics, and the Sun has an importance both as
  the star that is most amenable to detailed study and as the star that
  has by far the biggest impact on the Earth and near-Earth environment
  through its radiative and particulate outputs. Over the past decades,
  studies of stars and of the Sun have become somewhat separate. But in
  recent years, the rapid advances in asteroseismology, as well as the
  quest to better understand solar and stellar dynamos, have emphasized
  once again the synergy between studies of the stars and the Sun. In
  this article I have selected two "grand challenges" both for their
  crucial importance and because I thnk that these two problems are
  tractable to significant progress in the next decade. They are (i)
  understanding how solar and stellar dynamos generate magnetic field,
  and (ii) improving the predictability of geo-effective space weather.

Title: Future mmVLBI Research with ALMA: A European vision
Authors: Tilanus, R. P. J.; Krichbaum, T. P.; Zensus, J. A.; Baudry,
   A.; Bremer, M.; Falcke, H.; Giovannini, G.; Laing, R.; van Langevelde,
   H. J.; Vlemmings, W.; Abraham, Z.; Afonso, J.; Agudo, I.; Alberdi,
   A.; Alcolea, J.; Altamirano, D.; Asadi, S.; Assaf, K.; Augusto, P.;
   Baczko, A-K.; Boeck, M.; Boller, T.; Bondi, M.; Boone, F.; Bourda,
   G.; Brajsa, R.; Brand, J.; Britzen, S.; Bujarrabal, V.; Cales, S.;
   Casadio, C.; Casasola, V.; Castangia, P.; Cernicharo, J.; Charlot,
   P.; Chemin, L.; Clenet, Y.; Colomer, F.; Combes, F.; Cordes, J.;
   Coriat, M.; Cross, N.; D'Ammando, F.; Dallacasa, D.; Desmurs, J-F.;
   Eatough, R.; Eckart, A.; Eisenacher, D.; Etoka, S.; Felix, M.; Fender,
   R.; Ferreira, M.; Freeland, E.; Frey, S.; Fromm, C.; Fuhrmann, L.;
   Gabanyi, K.; Galvan-Madrid, R.; Giroletti, M.; Goddi, C.; Gomez, J.;
   Gourgoulhon, E.; Gray, M.; di Gregorio, I.; Greimel, R.; Grosso, N.;
   Guirado, J.; Hada, K.; Hanslmeier, A.; Henkel, C.; Herpin, F.; Hess,
   P.; Hodgson, J.; Horns, D.; Humphreys, E.; Hutawarakorn Kramer, B.;
   Ilyushin, V.; Impellizzeri, V.; Ivanov, V.; Julião, M.; Kadler, M.;
   Kerins, E.; Klaassen, P.; van 't Klooster, K.; Kording, E.; Kozlov,
   M.; Kramer, M.; Kreikenbohm, A.; Kurtanidze, O.; Lazio, J.; Leite,
   A.; Leitzinger, M.; Lepine, J.; Levshakov, S.; Lico, R.; Lindqvist,
   M.; Liuzzo, E.; Lobanov, A.; Lucas, P.; Mannheim, K.; Marcaide, J.;
   Markoff, S.; Martí-Vidal, I.; Martins, C.; Masetti, N.; Massardi,
   M.; Menten, K.; Messias, H.; Migliari, S.; Mignano, A.; Miller-Jones,
   J.; Minniti, D.; Molaro, P.; Molina, S.; Monteiro, A.; Moscadelli,
   L.; Mueller, C.; Müller, A.; Muller, S.; Niederhofer, F.; Odert,
   P.; Olofsson, H.; Orienti, M.; Paladino, R.; Panessa, F.; Paragi,
   Z.; Paumard, T.; Pedrosa, P.; Pérez-Torres, M.; Perrin, G.; Perucho,
   M.; Porquet, D.; Prandoni, I.; Ransom, S.; Reimers, D.; Rejkuba, M.;
   Rezzolla, L.; Richards, A.; Ros, E.; Roy, A.; Rushton, A.; Savolainen,
   T.; Schulz, R.; Silva, M.; Sivakoff, G.; Soria-Ruiz, R.; Soria, R.;
   Spaans, M.; Spencer, R.; Stappers, B.; Surcis, G.; Tarchi, A.; Temmer,
   M.; Thompson, M.; Torrelles, J.; Truestedt, J.; Tudose, V.; Venturi,
   T.; Verbiest, J.; Vieira, J.; Vielzeuf, P.; Vincent, F.; Wex, N.;
   Wiik, K.; Wiklind, T.; Wilms, J.; Zackrisson, E.; Zechlin, H.
Bibcode: 2014arXiv1406.4650T
Altcode:
  Very long baseline interferometry at millimetre/submillimetre
  wavelengths (mmVLBI) offers the highest achievable spatial
  resolution at any wavelength in astronomy. The anticipated inclusion
  of ALMA as a phased array into a global VLBI network will bring
  unprecedented sensitivity and a transformational leap in capabilities
  for mmVLBI. Building on years of pioneering efforts in the US and
  Europe the ongoing ALMA Phasing Project (APP), a US-led international
  collaboration with MPIfR-led European contributions, is expected to
  deliver a beamformer and VLBI capability to ALMA by the end of 2014
  (APP: Fish et al. 2013, arXiv:1309.3519). This report focuses on
  the future use of mmVLBI by the international users community from
  a European viewpoint. Firstly, it highlights the intense science
  interest in Europe in future mmVLBI observations as compiled from
  the responses to a general call to the European community for future
  research projects. A wide range of research is presented that includes,
  amongst others: - Imaging the event horizon of the black hole at the
  centre of the Galaxy - Testing the theory of General Relativity an/or
  searching for alternative theories - Studying the origin of AGN jets
  and jet formation - Cosmological evolution of galaxies and BHs, AGN
  feedback - Masers in the Milky Way (in stars and star-forming regions) -
  Extragalactic emission lines and astro-chemistry - Redshifted absorption
  lines in distant galaxies and study of the ISM and circumnuclear gas -
  Pulsars, neutron stars, X-ray binaries - Testing cosmology - Testing
  fundamental physical constants

Title: On the shape of the mass-function of dense clumps in the Hi-GAL
    fields . II. Using Bayesian inference to study the clump mass function
Authors: Olmi, L.; Anglés-Alcázar, D.; Elia, D.; Molinari, S.;
   Pestalozzi, M.; Pezzuto, S.; Schisano, E.; Testi, L.; Thompson, M.
Bibcode: 2014A&A...564A..87O
Altcode: 2013arXiv1311.2736O
  Context. Stars form in dense, dusty clumps of molecular clouds, but
  little is known about their origin, their evolution, and their detailed
  physical properties. In particular, the relationship between the mass
  distribution of these clumps (also known as the "clump mass function",
  or CMF) and the stellar initial mass function (IMF) is still poorly
  understood. <BR /> Aims: To better understand how the CMF evolve toward
  the IMF and to discern the "true" shape of the CMF, large samples of
  bona-fide pre- and proto-stellar clumps are required. Two such datasets
  obtained from the Herschel infrared GALactic Plane Survey (Hi-GAL)
  have been described in Paper I. Robust statistical methods are needed
  to infer the parameters describing the models used to fit the CMF and
  to compare the competing models themselves. <BR /> Methods: In this
  paper, we apply Bayesian inference to the analysis of the CMF of the
  two regions discussed in Paper I. First, we determine the posterior
  probability distribution for each of the fitted parameters. Then,
  we carry out a quantitative comparison of the models used to fit
  the CMF. <BR /> Results: We have compared several methods of sampling
  posterior distributions and calculating global likelihoods, and we have
  also analyzed the impact of the choice of priors and the influence
  of various constraints on the statistical conclusions for the values
  of model parameters. We find that both parameter estimation and model
  comparison depend on the choice of parameter priors. <BR /> Conclusions:
  Our results confirm our earlier conclusion that the CMFs of the two
  Hi-GAL regions studied here have very similar shapes but different mass
  scales. Furthermore, the lognormal model appears to better describe
  the CMF measured in the two Hi-GAL regions studied here. However, this
  preliminary conclusion is dependent on the choice of parameter priors.

Title: Study of KIC 8561221 observed by Kepler: an early red giant
    showing depressed dipolar modes
Authors: García, R. A.; Pérez Hernández, F.; Benomar, O.; Silva
   Aguirre, V.; Ballot, J.; Davies, G. R.; Doğan, G.; Stello, D.;
   Christensen-Dalsgaard, J.; Houdek, G.; Lignières, F.; Mathur, S.;
   Takata, M.; Ceillier, T.; Chaplin, W. J.; Mathis, S.; Mosser, B.;
   Ouazzani, R. M.; Pinsonneault, M. H.; Reese, D. R.; Régulo, C.;
   Salabert, D.; Thompson, M. J.; van Saders, J. L.; Neiner, C.; De
   Ridder, J.
Bibcode: 2014A&A...563A..84G
Altcode: 2013arXiv1311.6990G
  Context. The continuous high-precision photometric observations
  provided by the CoRoT and Kepler space missions have allowed us to
  understand the structure and dynamics of red giants better using
  asteroseismic techniques. A small fraction of these stars show
  dipole modes with unexpectedly low amplitudes. The reduction in
  amplitude is more pronounced for stars with a higher frequency of
  maximum power, ν<SUB>max</SUB>. <BR /> Aims: In this work we want to
  characterise KIC 8561221 in order to confirm that it is currently the
  least evolved star among this peculiar subset and to discuss several
  hypotheses that could help explain the reduction of the dipole mode
  amplitudes. <BR /> Methods: We used Kepler short- and long-cadence
  data combined with spectroscopic observations to infer the stellar
  structure and dynamics of KIC 8561221. We then discussed different
  scenarios that could contribute to reducing the dipole amplitudes,
  such as a fast-rotating interior or the effect of a magnetic field
  on the properties of the modes. We also performed a detailed study
  of the inertia and damping of the modes. <BR /> Results: We have
  been able to characterise 36 oscillations modes, in particular, a
  few dipole modes above ν<SUB>max</SUB> that exhibit nearly normal
  amplitudes. The frequencies of all the measured modes were used
  to determine the overall properties and the internal structure of
  the star. We have inferred a surface rotation period of ~91 days
  and uncovered a variation in the surface magnetic activity during
  the last 4 years. The analysis of the convective background did not
  reveal any difference compared to "normal" red giants. As expected,
  the internal regions of the star probed by the ℓ = 2 and 3 modes
  spin 4 to 8 times faster than the surface. <BR /> Conclusions: With
  our grid of standard models we are able to properly fit the observed
  frequencies. Our model calculation of mode inertia and damping give
  no explanation for the depressed dipole modes. A fast-rotating core
  is also ruled out as a possible explanation. Finally, we do not have
  any observational evidence of a strong deep magnetic field inside the
  star. <P />Table 3 and Appendix A are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201322823/olm">http://www.aanda.org</A>

Title: First Images from the Cript Muon Tomography System
Authors: Armitage, J.; Botte, J.; Boudjemline, K.; Erlandson, A.;
   Robichaud, A.; Bueno, J.; Bryman, D.; Gazit, R.; Hydomako, R.; Liu,
   Z.; Anghel, V.; Golovko, V. V.; Jewett, C.; Jonkmans, G.; Thompson,
   M.; Charles, E.; Gallant, G.; Drouin, P. -L.; Waller, D.; Stocki,
   T. J.; Cousins, T.; Noel, S.
Bibcode: 2014IJMPS..2760129A
Altcode:
  The CRIPT Cosmic Ray Imaging and Passive Tomography system began
  data taking in September 2012. CRIPT is a “proof of principle”
  muon tomography system originally proposed to inspect cargo in
  shipping containers and to determine the presence of special nuclear
  materials. CRIPT uses 4 layers of 2 m x 2 m scintillation counter
  trackers, each layer measuring two coordinates. Two layers are used
  to track the incoming muon and two for the outgoing muon allowing
  the trajectories of the muon to be determined. The target volume
  is divided into voxels, and a Point of Closest Approach algorithm
  is used to determine the number of scattering events in each voxel,
  producing a 3D image. The system has been tested with various targets
  of depleted uranium, lead bricks, and tungsten rods. Data on the
  positional resolution has been taken and the intrinsic resolution
  is unfolded with the help of a simulation using GEANT4. The next
  steps include incorporation of data from the spectrometer section,
  which will assist in determining the muon's momentum and improve the
  determination of the density of the target.

Title: Oscillations and Surface Rotation of Red Giant Stars
Authors: Hedges, C.; Mathur, S.; Thompson, M. J.; MacGregor, K. B.
Bibcode: 2013ASPC..479..197H
Altcode: 2013arXiv1308.0644H
  More than 15000 red giants observed by Kepler for a duration of almost
  one year became public at the beginning of this year. We analysed a
  subsample of 416 stars to determine the global properties of acoustic
  modes (mean large separation and frequency of maximum power). Using
  the effective temperature from the Kepler Input Catalog, we derived
  a first estimate of the masses and radii of these stars. Finally, we
  applied wavelets to look for a signature of surface rotation, which
  relies on the presence of spots or other surface features crossing
  the stellar visible disk.

Title: The Torsional Oscillation and the Timing of the Solar Cycle:
    Is it Maximum Yet?
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R.;
   Larson, T. P.; Schou, J.; Thompson, M. J.
Bibcode: 2013ASPC..478..303H
Altcode:
  After the late start to Cycle 24 there are some indications that
  activity may have peaked as early as late 2011 and that the polar-field
  reversal has already occurred in the North. We use helioseismic
  measurements of the migrating zonal flow pattern known as the torsional
  oscillation to estimate the length of the solar cycle, and find that
  it has held steady at about 12.3 years since late 2009, which would
  point to solar maximum in 2013 as expected.

Title: The High-latitude Branch of the Solar Torsional Oscillation
    in the Rising Phase of Cycle 24
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R.;
   Larson, T. P.; Rempel, M.; Schou, J.; Thompson, M. J.
Bibcode: 2013ApJ...767L..20H
Altcode:
  We use global heliseismic data from the Global Oscillation Network
  Group, the Michelson Doppler Imager on board the Solar and Heliospheric
  Observatory, and the Helioseismic and Magnetic Imager on board the Solar
  Dynamics Observatory, to examine the behavior, during the rising phase
  of Solar Cycle 24, of the migrating zonal flow pattern known as the
  torsional oscillation. Although the high-latitude part of the pattern
  appears to be absent in the new cycle when the flows are derived by
  subtracting a mean across a full solar cycle, it can be seen if we
  subtract the mean over a shorter period in the rising phase of each
  cycle, and these two mean rotation profiles differ significantly
  at high latitudes. This indicates that the underlying high-latitude
  rotation has changed; we speculate that this is in response to weaker
  polar fields, as suggested by a recent model.

Title: A New Multi-Wavelength Synoptic Network for Solar Physics
    and Space Weather
Authors: Hill, Frank; Roth, Markus; Thompson, Michael
Bibcode: 2013EGUGA..1511892H
Altcode:
  Continuous solar observations are important for many research topics
  in solar physics, such as magnetic field evolution, flare and CME
  characteristics, and p-mode oscillation measurements. In addition,
  space weather operations require constant streams of solar data as
  input. The deployment of a number of identical instruments around
  the world in a network has proven to be a very effective strategy for
  obtaining nearly continuous solar observations. The financial costs of
  a network are 1-2 orders of magnitude lower than space-based platforms;
  network instrumentation can be easily accessed for maintenance and
  upgrades; and telemetry bandwidth is readily available. Currently,
  there are two solar observing networks with consistent instruments:
  BiSON and GONG, both designed primarily for helioseismology. In
  addition, GONG has been augmented with continual magnetic field
  measurements and H-alpha imagery, with both being used for space
  weather operational purposes. However, GONG is now 18 years old and
  getting increasingly more challenging to maintain. There are also at
  least three scientific motivations for a multi-wavelength network:
  Recent advances in helioseismology have demonstrated the need for
  multi-wavelength observations to allow more accurate interpretation
  of the structure and dynamics below sunspots. Vector magnetometry
  would greatly benefit from multi-wavelength observations to provide
  height information and resolve the azimuthal ambiguity. Finally,
  space weather operations always need a consistent reliable source of
  continual solar data. This presentation will outline the scientific
  need for a multi-wavelength network, and discuss some concepts for
  the design of the instrumentation. A workshop on the topic will be
  held in Boulder this April.

Title: On the shape of the mass-function of dense clumps in the
    Hi-GAL fields . I. Spectral energy distribution determination and
    global properties of the mass-functions
Authors: Olmi, L.; Anglés-Alcázar, D.; Elia, D.; Molinari, S.;
   Montier, L.; Pestalozzi, M.; Pezzuto, S.; Polychroni, D.; Ristorcelli,
   I.; Rodon, J.; Schisano, E.; Smith, M. D.; Testi, L.; Thompson, M.
Bibcode: 2013A&A...551A.111O
Altcode: 2012arXiv1209.4465O
  Context. Stars form in dense, dusty clumps of molecular clouds, but
  little is known about their origin and evolution. In particular, the
  relationship between the mass distribution of these clumps (also known
  as the clump mass function or CMF) and the stellar initial mass function
  (IMF), is still poorly understood. <BR /> Aims: To discern the "true"
  shape of the CMF and to better understand how the CMF may evolve toward
  the IMF, large samples of bona-fide pre- and proto-stellar clumps are
  required. The sensitive observations of the Herschel Space Observatory
  (HSO) are now allowing us to look at large clump populations in various
  clouds with different physical conditions. <BR /> Methods: We analyze
  two fields in the Galactic plane mapped by HSO during its science
  demonstration phase (SDP), as part of the more complete and unbiased
  Herschel infrared GALactic Plane Survey (Hi-GAL). These fields underwent
  a source-extraction and flux-estimation pipeline, which allowed us to
  obtain a sample with thousands of clumps. Starless and proto-stellar
  clumps were separated using both color and positional criteria to find
  those coincident with MIPS 24 μm sources. We describe the probability
  density functions of the power-law and lognormal models that were used
  to fit the CMFs. For the lognormal model we applied several statistical
  techniques to the data and compared their results. <BR /> Results: The
  CMFs of the two SDP fields show very similar shapes, but very different
  mass scales. This similarity is confirmed by the values of the best-fit
  parameters of either the power-law or lognormal model. The power-law
  model leads to almost identical CMF slopes, whereas the lognormal
  model shows that the CMFs have similar widths. <BR /> Conclusions:
  The similar CMF shape but different mass scale represents an evidence
  that the overall process of star formation in the two regions is very
  different. When comparing with the IMF, we find that the width of the
  IMF is narrower than the measured widths of the CMF in the two SDP
  fields. This may suggest that an additional mass selection occurs in
  later stages of gravitational collapse.

Title: Minor Planet Observations [J13 La Palma-Liverpool Telescope]
Authors: Foster, P.; Ashcroft, H.; Robinson, D.; Ellender, N.; Hill,
   S.; Browne, J.; Thompson, M.; Thomas, H.; Mill, C.; Edwards, J.;
   Martin, S.; Thorpe, C.; Llewellyn-Davies, S.; Hewitt, J.; Kettle,
   P.; Woodruff, K.; Edwar, J.; Emmett, J.; Culshaw, B.
Bibcode: 2013MPC..82706...1B
Altcode:
  No abstract at ADS

Title: A Coral Sea Rehearsal for the Eclipse Megamovie
Authors: Hudson, H. S.; Davey, A. R.; Ireland, J.; Jones, L.; Mcintosh,
   S. W.; Paglierani, R.; Pasachoff, J. M.; Peticolas, L. M.; Russell,
   R. M.; Suarez Sola, F. I.; Sutherland, L.; Thompson, M. J.
Bibcode: 2012AGUFMSH11C..06H
Altcode:
  The "Eclipse on the Coral Sea" - 13/14 November 2012 (GMT/Australia)
  - will have happened already. Our intention is to have used this
  opportunity as a trial run for the eclipse in 2017, which features
  1.5 hours of totality across the whole width of the continental
  US. Conceived first and foremost as an education and public outreach
  activity, the plan is to engage the public in solar science and
  technology by providing a way for them to include images they have taken
  of the solar eclipse, into a movie representation of coronal evolution
  in time. This project will assimilate as much eclipse photography as
  possible from the public. The resulting movie(s) will cover all ranges
  of expertise, and at the basic smartphone or hand-held digital camera
  level, we expect to have obtained a huge number of images in the case
  of good weather conditions. The capability of modern digital technology
  to handle such a data flow is new. The basic purpose of this and the
  2017 Megamovie observations is to explore this capability and its
  ability to engage people from many different communities in the solar
  science, astronomy, mathematics, and technology. The movie in 2017,
  especially, may also have important science impact because of the
  uniqueness of the corona as seen under eclipse conditions. In this
  presentation we will describe our smartphone application development
  (see the "Transit of Venus" app for a role model here). We will also
  summarize data acquisition via both the app and more traditional web
  interfaces. Although for the Coral Sea eclipse event we don't expect to
  have a movie product by the time of the AGU, for the 2017 event we do
  intend to assemble the heterogenous data into beautiful movies within a
  short space of time after the eclipse. These movies may have relatively
  low resolution but would extend to the base of the corona. We encourage
  participation in the 2012 observations, noting that no total eclipse,
  prior to 2017, will occur in a region with good infrastructure for
  extended observations. The National Center for Atmospheric Research is
  sponsored by the National Science Foundation. The Megamovie project
  is supported by NSF grant AGS-1247226, and JMP's eclipse work about
  the eclipses of 2012 is supported by NSF grant AGS-1047726.

Title: Fundamental Properties of Stars Using Asteroseismology from
    Kepler and CoRoT and Interferometry from the CHARA Array
Authors: Huber, D.; Ireland, M. J.; Bedding, T. R.; Brandão, I. M.;
   Piau, L.; Maestro, V.; White, T. R.; Bruntt, H.; Casagrande, L.;
   Molenda-Żakowicz, J.; Silva Aguirre, V.; Sousa, S. G.; Barclay,
   T.; Burke, C. J.; Chaplin, W. J.; Christensen-Dalsgaard, J.; Cunha,
   M. S.; De Ridder, J.; Farrington, C. D.; Frasca, A.; García, R. A.;
   Gilliland, R. L.; Goldfinger, P. J.; Hekker, S.; Kawaler, S. D.;
   Kjeldsen, H.; McAlister, H. A.; Metcalfe, T. S.; Miglio, A.; Monteiro,
   M. J. P. F. G.; Pinsonneault, M. H.; Schaefer, G. H.; Stello, D.;
   Stumpe, M. C.; Sturmann, J.; Sturmann, L.; ten Brummelaar, T. A.;
   Thompson, M. J.; Turner, N.; Uytterhoeven, K.
Bibcode: 2012ApJ...760...32H
Altcode: 2012arXiv1210.0012H
  We present results of a long-baseline interferometry campaign using
  the PAVO beam combiner at the CHARA Array to measure the angular
  sizes of five main-sequence stars, one subgiant and four red
  giant stars for which solar-like oscillations have been detected
  by either Kepler or CoRoT. By combining interferometric angular
  diameters, Hipparcos parallaxes, asteroseismic densities, bolometric
  fluxes, and high-resolution spectroscopy, we derive a full set of
  near-model-independent fundamental properties for the sample. We
  first use these properties to test asteroseismic scaling relations
  for the frequency of maximum power (ν<SUB>max</SUB>) and the large
  frequency separation (Δν). We find excellent agreement within the
  observational uncertainties, and empirically show that simple estimates
  of asteroseismic radii for main-sequence stars are accurate to &lt;~
  4%. We furthermore find good agreement of our measured effective
  temperatures with spectroscopic and photometric estimates with mean
  deviations for stars between T <SUB>eff</SUB> = 4600-6200 K of -22 ±
  32 K (with a scatter of 97 K) and -58 ± 31 K (with a scatter of 93 K),
  respectively. Finally, we present a first comparison with evolutionary
  models, and find differences between observed and theoretical properties
  for the metal-rich main-sequence star HD 173701. We conclude that
  the constraints presented in this study will have strong potential
  for testing stellar model physics, in particular when combined with
  detailed modeling of individual oscillation frequencies.

Title: Measurements of CO Redshifts with Z-Spec for Lensed
    Submillimeter Galaxies Discovered in the H-ATLAS Survey
Authors: Lupu, R. E.; Scott, K. S.; Aguirre, J. E.; Aretxaga, I.; Auld,
   R.; Barton, E.; Beelen, A.; Bertoldi, F.; Bock, J. J.; Bonfield, D.;
   Bradford, C. M.; Buttiglione, S.; Cava, A.; Clements, D. L.; Cooke,
   J.; Cooray, A.; Dannerbauer, H.; Dariush, A.; De Zotti, G.; Dunne,
   L.; Dye, S.; Eales, S.; Frayer, D.; Fritz, J.; Glenn, J.; Hughes,
   D. H.; Ibar, E.; Ivison, R. J.; Jarvis, M. J.; Kamenetzky, J.; Kim,
   S.; Lagache, G.; Leeuw, L.; Maddox, S.; Maloney, P. R.; Matsuhara,
   H.; Murphy, E. J.; Naylor, B. J.; Negrello, M.; Nguyen, H.; Omont,
   A.; Pascale, E.; Pohlen, M.; Rigby, E.; Rodighiero, G.; Serjeant,
   S.; Smith, D.; Temi, P.; Thompson, M.; Valtchanov, I.; Verma, A.;
   Vieira, J. D.; Zmuidzinas, J.
Bibcode: 2012ApJ...757..135L
Altcode: 2010arXiv1009.5983L
  We present new observations from Z-Spec, a broadband 185-305 GHz
  spectrometer, of five submillimeter bright lensed sources selected
  from the Herschel-Astrophysical Terahertz Large Area Survey science
  demonstration phase catalog. We construct a redshift-finding algorithm
  using combinations of the signal to noise of all the lines falling
  in the Z-Spec bandpass to determine redshifts with high confidence,
  even in cases where the signal to noise in individual lines is low. We
  measure the dust continuum in all sources and secure CO redshifts for
  four out of five (z ~ 1.5-3). In one source, SDP.17, we tentatively
  identify two independent redshifts and a water line, confirmed at z =
  2.308. Our sources have properties characteristic of dusty starburst
  galaxies, with magnification-corrected star formation rates of 10<SUP>2
  - 3</SUP> M <SUB>⊙</SUB> yr<SUP>-1</SUP>. Lower limits for the dust
  masses (~ a few 10<SUP>8</SUP> M <SUB>⊙</SUB>) and spatial extents
  (~1 kpc equivalent radius) are derived from the continuum spectral
  energy distributions, corresponding to dust temperatures between 54
  and 69 K. In the local thermodynamic equilibrium (LTE) approximation,
  we derive relatively low CO excitation temperatures (lsim 100 K)
  and optical depths (τ &lt;~ 1). Performing a non-LTE excitation
  analysis using RADEX, we find that the CO lines measured by Z-Spec
  (from J = 4 → 3 to 10 → 9, depending on the galaxy) localize the
  best solutions to either a high-temperature/low-density region or a
  low/temperature/high-density region near the LTE solution, with the
  optical depth varying accordingly. Observations of additional CO lines,
  CO(1-0) in particular, are needed to constrain the non-LTE models.

Title: Fast Rotating Solar-like Stars Using Asteroseismic Datasets
Authors: García, R. A.; Ceillier, T.; Campante, T. L.; Davies, G. R.;
   Mathur, S.; Suárez, J. C.; Ballot, J.; Benomar, O.; Bonanno, A.;
   Brun, A. S.; Chaplin, W. J.; Christensen-Dalsgaard, J.; Deheuvels,
   S.; Elsworth, Y.; Handberg, R.; Hekker, S.; Jiménez, A.; Karoff, C.;
   Kjeldsen, H.; Mathis, S.; Mosser, B.; Pallé, P. L.; Pinsonneault, M.;
   Régulo, C.; Salabert, D.; Silva Aguirre, V.; Stello, D.; Thompson,
   M. J.; Verner, G.; PE11 Team of Kepler WG#1
Bibcode: 2012ASPC..462..133G
Altcode: 2011arXiv1109.6488G
  The NASA Kepler mission is providing an unprecedented set of
  asteroseismic data. In particular, short-cadence light-curves (∼ 60
  s samplings), allow us to study solar-like stars covering a wide range
  of masses, spectral types and evolutionary stages. Oscillations have
  been observed in around 600 out of 2000 stars observed for one month
  during the survey phase of the Kepler mission. The measured light
  curves can present features related to the surface magnetic activity
  (starspots) and, thus we are able to obtain a good estimate of the
  surface (differential) rotation. In this work we establish the basis
  of such research and we show a potential method to find stars with
  fast surface rotation.

Title: Seismic Analysis of Four Solar-like Stars Observed during
    More Than Eight Months by Kepler
Authors: Mathur, S.; Campante, T. L.; Handberg, R.; García, R. A.;
   Appourchaux, T.; Bedding, T. R.; Mosser, B.; Chaplin, W. J.; Ballot,
   J.; Benomar, O.; Bonanno, A.; Corsaro, E.; Gaulme, P.; Hekker,
   S.; Régulo, C.; Salabert, D.; Verner, G.; White, T. R.; Brandão,
   I. M.; Creevey, O. L.; Dogan, G.; Bazot, M.; Cunha, M. S.; Elsworth,
   Y.; Huber, D.; Hale, S. J.; Houdek, G.; Karoff, C.; Lundkvist, M.;
   Metcalfe, T. S.; Molenda-Zakowicz, J.; Monteiro, M. J. P. F. G.;
   Thompson, M. J.; Stello, D.; Christensen-Dalsgaard, J.; Gilliland,
   R. L.; Kawaler, S. D.; Kjeldsen, H.; Clarke, B. D.; Girouard, F. R.;
   Hall, J. R.; Quintana, E. V.; Sanderfer, D. T.; Seader, S. E.
Bibcode: 2012ASPC..462..180M
Altcode: 2011arXiv1110.0135M
  Having started science operations in May 2009, the Kepler photometer
  has been able to provide exquisite data for solar-like stars. Five
  out of the 42 stars observed continuously during the survey phase
  show evidence of oscillations, even though they are rather faint
  (magnitudes from 10.5 to 12). In this paper, we present an overview
  of the results of the seismic analysis of 4 of these stars observed
  during more than eight months.

Title: Solar and stellar activity: diagnostics and indices
Authors: Judge, Philip G.; Thompson, Michael J.
Bibcode: 2012IAUS..286...15J
Altcode: 2012arXiv1201.4625J
  We summarize the fifty-year concerted effort to place the ``activity''
  of the Sun in the context of the stars. As a working definition of solar
  activity in the context of stars, we adopt those globally-observable
  variations on time scales below thermal time scales, of ~10<SUP>5</SUP>
  yr for the convection zone. So defined, activity is dominated by
  magnetic-field evolution, including the 22-year Hale cycle, the typical
  time it takes for the quasi-periodic reversal in which the global
  magnetic-field takes place. This is accompanied by sunspot variations
  with 11 year periods, known since the time of Schwabe, as well as faster
  variations due to rotation of active regions and flaring. ``Diagnostics
  and indices'' are terms given to the indirect signatures of varying
  magnetic-fields, including the photometric (broad-band) variations
  associated with the sunspot cycle, and variations of the accompanying
  heated plasma in higher layers of stellar atmospheres seen at special
  optical wavelengths, and UV and X-ray wavelengths. Our attention is
  also focussed on the theme of the Symposium by examining evidence for
  deep and extended minima of stars, and placing the 70-year long solar
  Maunder Minimum into a stellar context.

Title: Latest Results on the Torsional Oscillation and Solar Cycle 25
Authors: Hill, Frank; Howe, R.; Schou, J.; Thompson, M.; Larson, T.;
   Komm, R.
Bibcode: 2012AAS...22012302H
Altcode:
  The Torsional Oscillation in the Sun is a zonal (East-West) flow
  that is slightly faster than the background differential rotation
  profile. The location of this flow slowly migrates in latitude over
  a period of several years. There are two branches of the flow: an
  equatorward branch that underlies the active regions, and a poleward
  branch. The timing of the equatorward migration is correlated with the
  timing of the solar cycle such that the activity for a cycle appears
  when the center of the flow reaches latitude 25 degrees. In addition,
  the poleward branch appears about 12 years prior to the activity for
  a cycle. Thus we should have observed the onset of Cycle 25 in 2008,
  but did not. This poster will update the observations to 2012, and
  present a new analysis that shows that the Cycle 25 flow appeared
  in 2010, but was hidden by a change in the background differential
  rotation profile. These results suggest that the next minimum will be
  two years longer than average, and that Cycle 25 will begin in 2022.

Title: A Uniform Asteroseismic Analysis of 22 Solar-type Stars
    Observed by Kepler
Authors: Mathur, S.; Metcalfe, T. S.; Woitaszek, M.; Bruntt, H.;
   Verner, G. A.; Christensen-Dalsgaard, J.; Creevey, O. L.; Doǧan, G.;
   Basu, S.; Karoff, C.; Stello, D.; Appourchaux, T.; Campante, T. L.;
   Chaplin, W. J.; García, R. A.; Bedding, T. R.; Benomar, O.; Bonanno,
   A.; Deheuvels, S.; Elsworth, Y.; Gaulme, P.; Guzik, J. A.; Handberg,
   R.; Hekker, S.; Herzberg, W.; Monteiro, M. J. P. F. G.; Piau, L.;
   Quirion, P. -O.; Régulo, C.; Roth, M.; Salabert, D.; Serenelli, A.;
   Thompson, M. J.; Trampedach, R.; White, T. R.; Ballot, J.; Brandão,
   I. M.; Molenda-Żakowicz, J.; Kjeldsen, H.; Twicken, J. D.; Uddin,
   K.; Wohler, B.
Bibcode: 2012ApJ...749..152M
Altcode: 2012arXiv1202.2844M
  Asteroseismology with the Kepler space telescope is providing not
  only an improved characterization of exoplanets and their host stars,
  but also a new window on stellar structure and evolution for the
  large sample of solar-type stars in the field. We perform a uniform
  analysis of 22 of the brightest asteroseismic targets with the highest
  signal-to-noise ratio observed for 1 month each during the first year
  of the mission, and we quantify the precision and relative accuracy
  of asteroseismic determinations of the stellar radius, mass, and age
  that are possible using various methods. We present the properties
  of each star in the sample derived from an automated analysis of the
  individual oscillation frequencies and other observational constraints
  using the Asteroseismic Modeling Portal (AMP), and we compare them to
  the results of model-grid-based methods that fit the global oscillation
  properties. We find that fitting the individual frequencies typically
  yields asteroseismic radii and masses to ~1% precision, and ages to
  ~2.5% precision (respectively, 2, 5, and 8 times better than fitting
  the global oscillation properties). The absolute level of agreement
  between the results from different approaches is also encouraging,
  with model-grid-based methods yielding slightly smaller estimates of
  the radius and mass and slightly older values for the stellar age
  relative to AMP, which computes a large number of dedicated models
  for each star. The sample of targets for which this type of analysis
  is possible will grow as longer data sets are obtained during the
  remainder of the mission.

Title: Estimating stellar mean density through seismic inversions
Authors: Reese, D. R.; Marques, J. P.; Goupil, M. J.; Thompson, M. J.;
   Deheuvels, S.
Bibcode: 2012A&A...539A..63R
Altcode: 2012arXiv1201.1844R
  Context. Determining the mass of stars is crucial both for improving
  stellar evolution theory and for characterising exoplanetary
  systems. Asteroseismology offers a promising way for estimating the
  stellar mean density. When combined with accurate radii determinations,
  such as are expected from Gaia, this yields accurate stellar masses. The
  main difficulty is finding the best way to extract the mean density
  of a star from a set of observed frequencies. <BR /> Aims: We seek to
  establish a new method for estimating the stellar mean density, which
  combines the simplicity of a scaling law while providing the accuracy
  of an inversion technique. <BR /> Methods: We provide a framework in
  which to construct and evaluate kernel-based linear inversions that
  directly yield the mean density of a star. We then describe three
  different inversion techniques (SOLA and two scaling laws) and apply
  them to the <ASTROBJ>Sun</ASTROBJ>, several test cases and three stars,
  <ASTROBJ>α Cen B</ASTROBJ>, <ASTROBJ>HD 49933</ASTROBJ> and <ASTROBJ>HD
  49385</ASTROBJ>, two of which are observed by CoRoT. <BR /> Results:
  The SOLA (subtractive optimally localised averages) approach and the
  scaling law based on the surface correcting technique described by
  Kjeldsen et al. (2008, ApJ, 683, L175) yield comparable results that
  can reach an accuracy of 0.5% and are better than scaling the large
  frequency separation. The reason for this is that the averaging kernels
  from the two first methods are comparable in quality and are better
  than what is obtained with the large frequency separation. It is also
  shown that scaling the large frequency separation is more sensitive
  to near-surface effects, but is much less affected by an incorrect
  mode identification. As a result, one can identify pulsation modes by
  looking for an ℓ and n assignment which provides the best agreement
  between the results from the large frequency separation and those from
  one of the two other methods. Non-linear effects are also discussed,
  as is the effects of mixed modes. In particular, we show that mixed
  modes bring little improvement to the mean density estimates because
  of their poorly adapted kernels.

Title: Disc frequencies for brown dwarfs in the Upper Scorpius OB
association: implications for brown dwarf formation theories
Authors: Riaz, B.; Lodieu, N.; Goodwin, S.; Stamatellos, D.;
   Thompson, M.
Bibcode: 2012MNRAS.420.2497R
Altcode: 2011arXiv1111.3929R
  We have investigated the brown dwarf (BD) and stellar disc fractions
  in the Upper Scorpius (USco) OB association and compared them with
  several other young regions. We have compiled the most complete
  sample of all spectroscopically confirmed BDs in USco and have made
  use of the Wide-field Infrared Survey Explorer (WISE) catalogue to
  identify the disc candidates. We report on the discovery of 12 new
  BD discs in USco, with spectral types between M6 and M8.5. The WISE
  colours for the new discs are similar to the primordial (transition)
  discs earlier detected in USco. Combining with previous surveys,
  we find the lowest inner disc fractions (∼20-25 per cent) for a
  wide range in stellar masses (∼0.01-4.0 M<SUB>⊙</SUB>) in the
  USco association. The low disc fractions for high-mass stars in USco
  (and the other clusters) are consistent with an evolutionary decline
  in inner disc frequency with age. However, BD disc fractions are
  higher than those for the stars in 1-3 Myr clusters, but very low in
  the ∼5 Myr old USco. Also, primordial BD discs are still visible
  in the ∼10 Myr old TW Hydrae association, whereas the higher mass
  stars have all transitioned to the debris stage by this age. The disc
  frequencies for BDs and low-mass stars do not show any dependence on
  the stellar density or the BD/star number ratio in a cluster. We also
  find no convincing evidence that any of the well-known disc dispersal
  mechanisms for stars are active in BD discs. We suggest that the large
  differences in the observed BD disc fractions between regions may well
  be due to different BD formation mechanisms and therefore different
  initial disc fractions/properties. <P />We also present a WISE spectral
  energy distribution classification scheme, based on the K<SUB>s</SUB>
  and WISE bands of 3.4-12 μm. We have determined certain thresholds in
  the WISE spectral slope versus spectral type diagrams to distinguish
  between the red population of Class I/II systems and the Class III
  sequence. We have found the WISE [3.4] - [12] colour to provide the
  best distinction between the photospheric and the disc population. Our
  work includes a comparison of the sensitivities of WISE and Spitzer
  disc surveys. We estimate that WISE can be incomplete for discs at
  spectral type later than M8 in distant clusters such as SOri. WISE
  should be able to recover the M8-M9 discs in the nearby young clusters.

Title: Kepler-21b: A 1.6 R <SUB>Earth</SUB> Planet Transiting the
    Bright Oscillating F Subgiant Star HD 179070
Authors: Howell, Steve B.; Rowe, Jason F.; Bryson, Stephen T.; Quinn,
   Samuel N.; Marcy, Geoffrey W.; Isaacson, Howard; Ciardi, David R.;
   Chaplin, William J.; Metcalfe, Travis S.; Monteiro, Mario J. P. F. G.;
   Appourchaux, Thierry; Basu, Sarbani; Creevey, Orlagh L.; Gilliland,
   Ronald L.; Quirion, Pierre-Olivier; Stello, Denis; Kjeldsen, Hans;
   Christensen-Dalsgaard, Jörgen; Elsworth, Yvonne; García, Rafael
   A.; Houdek, Günter; Karoff, Christoffer; Molenda-Żakowicz, Joanna;
   Thompson, Michael J.; Verner, Graham A.; Torres, Guillermo; Fressin,
   Francois; Crepp, Justin R.; Adams, Elisabeth; Dupree, Andrea; Sasselov,
   Dimitar D.; Dressing, Courtney D.; Borucki, William J.; Koch, David
   G.; Lissauer, Jack J.; Latham, David W.; Buchhave, Lars A.; Gautier,
   Thomas N., III; Everett, Mark; Horch, Elliott; Batalha, Natalie M.;
   Dunham, Edward W.; Szkody, Paula; Silva, David R.; Mighell, Ken;
   Holberg, Jay; Ballot, Jerôme; Bedding, Timothy R.; Bruntt, Hans;
   Campante, Tiago L.; Handberg, Rasmus; Hekker, Saskia; Huber, Daniel;
   Mathur, Savita; Mosser, Benoit; Régulo, Clara; White, Timothy R.;
   Christiansen, Jessie L.; Middour, Christopher K.; Haas, Michael R.;
   Hall, Jennifer R.; Jenkins, Jon M.; McCaulif, Sean; Fanelli, Michael
   N.; Kulesa, Craig; McCarthy, Don; Henze, Christopher E.
Bibcode: 2012ApJ...746..123H
Altcode: 2011arXiv1112.2165H
  We present Kepler observations of the bright (V = 8.3), oscillating
  star HD 179070. The observations show transit-like events which
  reveal that the star is orbited every 2.8 days by a small, 1.6 R
  <SUB>Earth</SUB> object. Seismic studies of HD 179070 using short
  cadence Kepler observations show that HD 179070 has a frequency-power
  spectrum consistent with solar-like oscillations that are acoustic
  p-modes. Asteroseismic analysis provides robust values for the mass
  and radius of HD 179070, 1.34 ± 0.06 M <SUB>⊙</SUB> and 1.86 ±
  0.04 R <SUB>⊙</SUB>, respectively, as well as yielding an age of
  2.84 ± 0.34 Gyr for this F5 subgiant. Together with ground-based
  follow-up observations, analysis of the Kepler light curves and
  image data, and blend scenario models, we conservatively show at the
  &gt;99.7% confidence level (3σ) that the transit event is caused by
  a 1.64 ± 0.04 R <SUB>Earth</SUB> exoplanet in a 2.785755 ± 0.000032
  day orbit. The exoplanet is only 0.04 AU away from the star and our
  spectroscopic observations provide an upper limit to its mass of ~10 M
  <SUB>Earth</SUB> (2σ). HD 179070 is the brightest exoplanet host star
  yet discovered by Kepler. <P />Based in part on observations obtained
  at the W. M. Keck Observatory, which is operated by the University
  of California and the California Institute of Technology, the Mayall
  telescope at Kitt Peak National Observatory, and the WIYN Observatory
  which is a joint facility of NOAO, University of Wisconsin-Madison,
  Indiana University, and Yale University.

Title: Solar-cycle variation of oscillation frequencies and surface
    magnetic field
Authors: Tan, S.; Thompson, M. J.; Centeno, R.
Bibcode: 2011AGUFMSH13B1933T
Altcode:
  We investigate the relationship between solar oscillation frequencies
  and surface magnetic fields over the course of the last solar
  cycle. Using MDI and GONG data, we study the variation in the even
  frequency-splitting coefficients a<SUB>k</SUB> (describing solar
  asphericity and effects of the magnetic field), and the variation in the
  coefficients B<SUB>k</SUB> of the latitudinal Lengendre decomposition
  of the surface magnetic field, during the period 1996 - 2010. We find
  a strong linear correlation between the a and B coefficients, during
  both the rising and declining phases of the solar cycle, consistent
  with results published in 2001 (Antia et al.). We also investigated
  different ways to handle the magnetic field decomposition at the poles,
  and find that the linear correlation persists, though with varying
  intercepts. The variation of slope with coefficient index that we find
  is non-monotonic, which disagrees with the previous study by Antia et
  al. (2001).

Title: Asteroseismic Diagrams from a Survey of Solar-like Oscillations
    with Kepler
Authors: White, Timothy R.; Bedding, Timothy R.; Stello, Dennis;
   Appourchaux, Thierry; Ballot, Jérôme; Benomar, Othman; Bonanno,
   Alfio; Broomhall, Anne-Marie; Campante, Tiago L.; Chaplin, William
   J.; Christensen-Dalsgaard, Jørgen; Corsaro, Enrico; Doǧan, Gülnur;
   Elsworth, Yvonne P.; Fletcher, Stephen T.; García, Rafael A.; Gaulme,
   Patrick; Handberg, Rasmus; Hekker, Saskia; Huber, Daniel; Karoff,
   Christoffer; Kjeldsen, Hans; Mathur, Savita; Mosser, Benoit; Monteiro,
   Mario J. P. F. G.; Régulo, Clara; Salabert, David; Silva Aguirre,
   Victor; Thompson, Michael J.; Verner, Graham; Morris, Robert L.;
   Sanderfer, Dwight T.; Seader, Shawn E.
Bibcode: 2011ApJ...742L...3W
Altcode: 2011arXiv1110.1375W
  Photometric observations made by the NASA Kepler Mission have led to a
  dramatic increase in the number of main-sequence and subgiant stars with
  detected solar-like oscillations. We present an ensemble asteroseismic
  analysis of 76 solar-type stars. Using frequencies determined from the
  Kepler time-series photometry, we have measured three asteroseismic
  parameters that characterize the oscillations: the large frequency
  separation (Δν), the small frequency separation between modes of
  l = 0 and l = 2 (δν<SUB>02</SUB>), and the dimensionless offset
  (epsilon). These measurements allow us to construct asteroseismic
  diagrams, namely the so-called Christensen-Dalsgaard diagram of
  δν<SUB>02</SUB> versus Δν, and the recently re-introduced epsilon
  diagram. We compare the Kepler results with previously observed
  solar-type stars and with theoretical models. The positions of
  stars in these diagrams places constraints on their masses and
  ages. Additionally, we confirm the observational relationship
  between epsilon and T <SUB>eff</SUB> that allows for the unambiguous
  determination of radial order and should help resolve the problem of
  mode identification in F stars.

Title: Constructing a One-solar-mass Evolutionary Sequence Using
    Asteroseismic Data from Kepler
Authors: Silva Aguirre, V.; Chaplin, W. J.; Ballot, J.; Basu,
   S.; Bedding, T. R.; Serenelli, A. M.; Verner, G. A.; Miglio, A.;
   Monteiro, M. J. P. F. G.; Weiss, A.; Appourchaux, T.; Bonanno,
   A.; Broomhall, A. M.; Bruntt, H.; Campante, T. L.; Casagrande, L.;
   Corsaro, E.; Elsworth, Y.; García, R. A.; Gaulme, P.; Handberg,
   R.; Hekker, S.; Huber, D.; Karoff, C.; Mathur, S.; Mosser, B.;
   Salabert, D.; Schönrich, R.; Sousa, S. G.; Stello, D.; White, T. R.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.; Kjeldsen,
   H.; Houdek, G.; Metcalfe, T. S.; Molenda-Żakowicz, J.; Thompson,
   M. J.; Caldwell, D. A.; Christiansen, J. L.; Wohler, B.
Bibcode: 2011ApJ...740L...2S
Altcode: 2011arXiv1108.2031S
  Asteroseismology of solar-type stars has entered a new era of
  large surveys with the success of the NASA Kepler mission, which
  is providing exquisite data on oscillations of stars across the
  Hertzsprung-Russell diagram. From the time-series photometry, the two
  seismic parameters that can be most readily extracted are the large
  frequency separation (Δν) and the frequency of maximum oscillation
  power (ν<SUB>max</SUB>). After the survey phase, these quantities
  are available for hundreds of solar-type stars. By scaling from solar
  values, we use these two asteroseismic observables to identify for the
  first time an evolutionary sequence of 1 M <SUB>sun</SUB> field stars,
  without the need for further information from stellar models. Comparison
  of our determinations with the few available spectroscopic results
  shows an excellent level of agreement. We discuss the potential of the
  method for differential analysis throughout the main-sequence evolution
  and the possibility of detecting twins of very well-known stars.

Title: Herschel-ATLAS: rapid evolution of dust in galaxies over the
    last 5 billion years
Authors: Dunne, L.; Gomez, H. L.; da Cunha, E.; Charlot, S.; Dye,
   S.; Eales, S.; Maddox, S. J.; Rowlands, K.; Smith, D. J. B.; Auld,
   R.; Baes, M.; Bonfield, D. G.; Bourne, N.; Buttiglione, S.; Cava, A.;
   Clements, D. L.; Coppin, K. E. K.; Cooray, A.; Dariush, A.; de Zotti,
   G.; Driver, S.; Fritz, J.; Geach, J.; Hopwood, R.; Ibar, E.; Ivison,
   R. J.; Jarvis, M. J.; Kelvin, L.; Pascale, E.; Pohlen, M.; Popescu, C.;
   Rigby, E. E.; Robotham, A.; Rodighiero, G.; Sansom, A. E.; Serjeant,
   S.; Temi, P.; Thompson, M.; Tuffs, R.; van der Werf, P.; Vlahakis, C.
Bibcode: 2011MNRAS.417.1510D
Altcode: 2010arXiv1012.5186D; 2011MNRAS.tmp.1395D
  We present the first direct and unbiased measurement of the evolution
  of the dust mass function of galaxies over the past 5 billion
  years of cosmic history using data from the Science Demonstration
  Phase of the Herschel-Astrophysical Terahertz Large Area Survey
  (Herschel-ATLAS). The sample consists of galaxies selected at 250 ?m
  which have reliable counterparts from the Sloan Digital Sky Survey
  (SDSS) at z &lt; 0.5, and contains 1867 sources. Dust masses are
  calculated using both a single-temperature grey-body model for the
  spectral energy distribution and also a model with multiple temperature
  components. The dust temperature for either model shows no trend with
  redshift. Splitting the sample into bins of redshift reveals a strong
  evolution in the dust properties of the most massive galaxies. At z=
  0.4-0.5, massive galaxies had dust masses about five times larger than
  in the local Universe. At the same time, the dust-to-stellar mass ratio
  was about three to four times larger, and the optical depth derived
  from fitting the UV-sub-mm data with an energy balance model was also
  higher. This increase in the dust content of massive galaxies at high
  redshift is difficult to explain using standard dust evolution models
  and requires a rapid gas consumption time-scale together with either a
  more top-heavy initial mass function (IMF), efficient mantle growth,
  less dust destruction or combinations of all three. This evolution
  in dust mass is likely to be associated with a change in overall
  interstellar medium mass, and points to an enhanced supply of fuel
  for star formation at earlier cosmic epochs.

Title: OT2_mthomp01_2: Confirming a sample of massive and luminous
    debris disks identified in the Herschel-ATLAS
Authors: Thompson, M.
Bibcode: 2011hers.prop.2085T
Altcode:
  Debris disks are the remains of planetary system formation, tracing
  the existence of planetesimal-sized objects in orbit around main
  sequence stars. Current and planned surveys of debris disks (including
  the Herschel Key Projects DEBRIS and DUNES) are deep surveys aimed
  at characterising the typical population of disks and targeted at
  samples of a few hundred nearby objects. These deep narrow surveys are
  relatively insensitive to the rarities in the debris disk population,
  some of which may be luminous and/or massive disks that have undergone
  recent disruptive collisional events. We have recently shown that the
  primarily extragalactic Key Project, the Herschel-ATLAS, can be used as
  a wide and shallow survey of debris disks by combining its excellent
  optical coverage and statistical techniques more commonly employed to
  identify galaxies. The combination of Herschel-ATLAS, DEBRIS and DUNES
  thus forms a powerful nested tier of surveys that will be sensitive
  to disks across the spectrum from exosolar analogues to rare disks
  that cannot be inferred from local populations. In this proposal we
  seek time to image 23 candidate disks that we have discovered in the
  Herschel-ATLAS with PACS so that we may confirm them as true debris
  disks and model their SEDs to extract mass, temperature and fractional
  luminosity. We will confirm whether these disk candidates are in fact
  the most luminous disks yet detected.

Title: Stellar hydrodynamics caught in the act: Asteroseismology
    with CoRoT and Kepler
Authors: Christensen-Dalsgaard, Jørgen; Thompson, Michael J.
Bibcode: 2011IAUS..271...32C
Altcode: 2011arXiv1104.5191C
  Asteroseismic investigations, particularly based on data on stellar
  oscillations from the CoRoT and Kepler space missions, are providing
  unique possibilities for investigating the properties of stellar
  interiors. This constitutes entirely new ways to study the effects
  of dynamic phenomena on stellar structure and evolution. Important
  examples are the extent of convection zones and the associated mixing
  and the direct and indirect effects of stellar rotation. In addition,
  the stellar oscillations themselves show very interesting dynamic
  behaviour. Here we discuss examples of the results obtained from such
  investigations, across the Hertzsprung-Russell diagram.

Title: Minor Planet Observations [F65 Haleakala-Faulkes Telescope
    North]
Authors: Fitzsimmons, A.; Roche, P.; Micheli, M.; Guido, E.; Lister,
   T.; Miller, P.; Tripp, A.; Holmes, R.; Miles, R.; Buzzi, L.; Fogl,
   S.; Howes, N.; Sostero, G.; Blyth, H.; Foglia, S.; Armstrong, J. D.;
   Sobaje, C. S.; Boaz, R. Z.; Thompson, M.; Pfluke, A.
Bibcode: 2011MPC..75687...1F
Altcode:
  No abstract at ADS

Title: Probing Subsurface Flows Around Sunspots with 3-Dimensional
    Ring Inversions
Authors: Featherstone, Nicholas Andrew; Hindman, Bradley W.; Thompson,
   Michael J.; Toomre, Juri
Bibcode: 2011shin.confE...7F
Altcode:
  We examine convective flows around sunspots as inferred through
  ring-analysis helioseismology of MDI Dopplergrams. These flow
  measurements were obtained using a novel 3-D inversion procedure
  termed Adaptively Resolved Ring-Diagram Inversions, or ARRDI, which
  uses sensitivity kernels based on the Born approximation. The ARRDI
  algorithm is multi-scale in nature, folding together information from
  tiles located at different positions on the solar surface and from
  tiles of different sizes, thus enabling fine control of the horizontal
  resolution and the probing depth. When we apply ARRDI to sunspots,
  we measure outflows persisting to depths of at least 7 Mm. In many
  instances, the surface outflow diminishes within the upper 3 Mm
  of the convection zone. Beyond 3 Mm, such outflows strengthen and
  attain peak amplitudes of 200 m/s at depths of 5-7 Mm. We discuss the
  implications of such a two-component outflow for understanding the
  magneto-hydrodynamic behavior and evolution of sunspots.

Title: Solar-like Oscillations in KIC 11395018 and KIC 11234888 from
    8 Months of Kepler Data
Authors: Mathur, S.; Handberg, R.; Campante, T. L.; García, R. A.;
   Appourchaux, T.; Bedding, T. R.; Mosser, B.; Chaplin, W. J.; Ballot,
   J.; Benomar, O.; Bonanno, A.; Corsaro, E.; Gaulme, P.; Hekker,
   S.; Régulo, C.; Salabert, D.; Verner, G.; White, T. R.; Brandão,
   I. M.; Creevey, O. L.; Doǧan, G.; Elsworth, Y.; Huber, D.; Hale,
   S. J.; Houdek, G.; Karoff, C.; Metcalfe, T. S.; Molenda-Żakowicz,
   J.; Monteiro, M. J. P. F. G.; Thompson, M. J.; Christensen-Dalsgaard,
   J.; Gilliland, R. L.; Kawaler, S. D.; Kjeldsen, H.; Quintana, E. V.;
   Sanderfer, D. T.; Seader, S. E.
Bibcode: 2011ApJ...733...95M
Altcode: 2011arXiv1103.4085M
  We analyze the photometric short-cadence data obtained with the Kepler
  mission during the first 8 months of observations of two solar-type
  stars of spectral types G and F: KIC 11395018 and KIC 11234888,
  respectively, the latter having a lower signal-to-noise ratio (S/N)
  compared with the former. We estimate global parameters of the acoustic
  (p) modes such as the average large and small frequency separations, the
  frequency of the maximum of the p-mode envelope, and the average line
  width of the acoustic modes. We were able to identify and to measure
  22 p-mode frequencies for the first star and 16 for the second one
  even though the S/N of these stars are rather low. We also derive some
  information about the stellar rotation periods from the analyses of the
  low-frequency parts of the power spectral densities. A model-independent
  estimation of the mean density, mass, and radius is obtained using the
  scaling laws. We emphasize the importance of continued observations
  for the stars with low S/N for an improved characterization of the
  oscillation modes. Our results offer a preview of what will be possible
  for many stars with the long data sets obtained during the remainder
  of the mission.

Title: A more realistic representation of overshoot at the base of
    the solar convective envelope as seen by helioseismology
Authors: Christensen-Dalsgaard, J.; Monteiro, M. J. P. F. G.; Rempel,
   M.; Thompson, M. J.
Bibcode: 2011MNRAS.414.1158C
Altcode: 2011MNRAS.tmp..440C; 2011arXiv1102.0235C
  The stratification near the base of the Sun's convective envelope
  is governed by processes of convective overshooting and element
  diffusion, and the region is widely believed to play a key role in
  the solar dynamo. The stratification in that region gives rise to
  a characteristic signal in the frequencies of solar p modes, which
  has been used to determine the depth of the solar convection zone
  and to investigate the extent of convective overshoot. Previous
  helioseismic investigations have shown that the Sun's spherically
  symmetric stratification in this region is smoother than that in a
  standard solar model without overshooting, and have ruled out simple
  models incorporating overshooting, which extend the region of adiabatic
  stratification and have a more-or-less abrupt transition to subadiabatic
  stratification at the edge of the overshoot region. In this paper we
  consider physically motivated models which have a smooth transition
  in stratification bridging the region from the lower convection zone
  to the radiative interior beneath. We find that such a model is in
  better agreement with the helioseismic data than a standard solar model.

Title: Preparation of Kepler light curves for asteroseismic analyses
Authors: García, R. A.; Hekker, S.; Stello, D.; Gutiérrez-Soto,
   J.; Handberg, R.; Huber, D.; Karoff, C.; Uytterhoeven, K.;
   Appourchaux, T.; Chaplin, W. J.; Elsworth, Y.; Mathur, S.; Ballot,
   J.; Christensen-Dalsgaard, J.; Gilliland, R. L.; Houdek, G.; Jenkins,
   J. M.; Kjeldsen, H.; McCauliff, S.; Metcalfe, T.; Middour, C. K.;
   Molenda-Zakowicz, J.; Monteiro, M. J. P. F. G.; Smith, J. C.; Thompson,
   M. J.
Bibcode: 2011MNRAS.414L...6G
Altcode: 2011arXiv1103.0382G
  The Kepler mission is providing photometric data of exquisite
  quality for the asteroseismic study of different classes of pulsating
  stars. These analyses place particular demands on the pre-processing
  of the data, over a range of time-scales from minutes to months. Here,
  we describe processing procedures developed by the Kepler Asteroseismic
  Science Consortium to prepare light curves that are optimized for the
  asteroseismic study of solar-like oscillating stars in which outliers,
  jumps and drifts are corrected.

Title: On the effects of rotation on acoustic stellar pulsations:
    validity domains of perturbative methods and close frequency pairs
Authors: Burke, K. D.; Reese, D. R.; Thompson, M. J.
Bibcode: 2011MNRAS.414.1119B
Altcode: 2011MNRAS.tmp..475B; 2011arXiv1102.0382B
  Pulsation frequencies of acoustic modes are calculated for realistic
  rotating stellar models using both a perturbative and a two-dimensional
  approach. A comparison between the two yields validity domains which
  are similar to those previously obtained in Reese et al. for polytropic
  models. One can also construct validity domains based on polynomial
  fits to the frequencies from the two-dimensional approach, and these
  also turn out to be similar, thus further confirming the agreement
  between the perturbative and the two-dimensional approaches at low
  rotation rates. Furthermore, as was previously shown in Espinosa
  et al., adjacent frequencies in multiplets come close together,
  thus forming pairs. This phenomenon, exclusive to two-dimensional
  calculations, is shown to be an unlikely explanation of the close
  frequency pairs observed in δ Scuti stars. A systematic search for
  all close frequency pairs in the calculated spectrum is also carried
  out. The number of close frequency pairs is shown to agree with what is
  expected based on a Poisson distribution, but does not match the number
  or distribution of close pairs in stars such as FG Vir. Furthermore,
  a lack of close frequency pairs appears at low rotation rates, where
  frequency multiplets do not overlap. δ Scuti stars currently reported
  as having close frequency pairs do not fall in this interval.

Title: Predicting the Detectability of Oscillations in Solar-type
    Stars Observed by Kepler
Authors: Chaplin, W. J.; Kjeldsen, H.; Bedding, T. R.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.;
   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.; Verner, G. A.; Batalha, N.; Borucki, W. J.;
   Brown, T. M.; Bryson, S. T.; Christiansen, J. L.; Clarke, B. D.;
   Jenkins, J. M.; Klaus, T. C.; Koch, D.; An, D.; Ballot, J.; Basu,
   S.; Benomar, O.; Bonanno, A.; Broomhall, A. -M.; Campante, T. L.;
   Corsaro, E.; Creevey, O. L.; Esch, L.; Gai, N.; Gaulme, P.; Hale,
   S. J.; Handberg, R.; Hekker, S.; Huber, D.; Mathur, S.; Mosser, B.;
   New, R.; Pinsonneault, M. H.; Pricopi, D.; Quirion, P. -O.; Régulo,
   C.; Roxburgh, I. W.; Salabert, D.; Stello, D.; Suran, M. D.
Bibcode: 2011ApJ...732...54C
Altcode: 2011arXiv1103.0702C
  Asteroseismology of solar-type stars has an important part to play
  in the exoplanet program of the NASA Kepler Mission. Precise and
  accurate inferences on the stellar properties that are made possible
  by the seismic data allow very tight constraints to be placed on the
  exoplanetary systems. Here, we outline how to make an estimate of the
  detectability of solar-like oscillations in any given Kepler target,
  using rough estimates of the temperature and radius, and the Kepler
  apparent magnitude.

Title: Evidence for the Impact of Stellar Activity on the
    Detectability of Solar-like Oscillations Observed by Kepler
Authors: Chaplin, W. J.; Bedding, T. R.; Bonanno, A.; Broomhall,
   A. -M.; García, R. A.; Hekker, S.; Huber, D.; Verner, G. A.;
   Basu, S.; Elsworth, Y.; Houdek, G.; Mathur, S.; Mosser, B.; New,
   R.; Stevens, I. R.; Appourchaux, T.; Karoff, C.; Metcalfe, T. S.;
   Molenda-Żakowicz, J.; Monteiro, M. J. P. F. G.; Thompson, M. J.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.; Kjeldsen,
   H.; Ballot, J.; Benomar, O.; Corsaro, E.; Campante, T. L.; Gaulme,
   P.; Hale, S. J.; Handberg, R.; Jarvis, E.; Régulo, C.; Roxburgh,
   I. W.; Salabert, D.; Stello, D.; Mullally, F.; Li, J.; Wohler, W.
Bibcode: 2011ApJ...732L...5C
Altcode: 2011arXiv1103.5570C
  We use photometric observations of solar-type stars, made by the NASA
  Kepler Mission, to conduct a statistical study of the impact of stellar
  surface activity on the detectability of solar-like oscillations. We
  find that the number of stars with detected oscillations falls
  significantly with increasing levels of activity. The results present
  strong evidence for the impact of magnetic activity on the properties
  of near-surface convection in the stars, which appears to inhibit
  the amplitudes of the stochastically excited, intrinsically damped
  solar-like oscillations.

Title: Large-scale Zonal Flows During the Solar Minimum -- Where Is
    Cycle 25?
Authors: Hill, Frank; Howe, R.; Komm, R.; Christensen-Dalsgaard, J.;
   Larson, T. P.; Schou, J.; Thompson, M. J.
Bibcode: 2011SPD....42.1610H
Altcode: 2011BAAS..43S.1610H
  The so-called torsional oscillation is a pattern of migrating zonal flow
  bands that move from mid-latitudes towards the equator and poles as the
  magnetic cycle progresses. Helioseismology allows us to probe these
  flows below the solar surface. The prolonged solar minimum following
  Cycle 23 was accompanied by a delay of 1.5 to 2 years in the migration
  of bands of faster rotation towards the equator. During the rising phase
  of Cycle 24, while the lower-level bands match those seen in the rising
  phase of Cycle 23, the rotation rate at middle and higher latitudes
  remains slower than it was at the corresponding phase in earlier cycles,
  perhaps reflecting the weakness of the polar fields. In addition,
  there is no evidence of the poleward flow associated with Cycle 25. We
  will present the latest results based on nearly sixteen years of global
  helioseismic observations from GONG and MDI, with recent results from
  HMI, and discuss the implications for the development of Cycle 25.

Title: Ensemble Asteroseismology of Solar-Type Stars with the NASA
    Kepler Mission
Authors: Chaplin, W. J.; Kjeldsen, H.; Christensen-Dalsgaard, J.;
   Basu, S.; Miglio, A.; Appourchaux, T.; Bedding, T. R.; Elsworth, Y.;
   García, R. A.; Gilliland, R. L.; Girardi, L.; Houdek, G.; Karoff,
   C.; Kawaler, S. D.; Metcalfe, T. S.; Molenda-Żakowicz, J.; Monteiro,
   M. J. P. F. G.; Thompson, M. J.; Verner, G. A.; Ballot, J.; Bonanno,
   A.; Brandão, I. M.; Broomhall, A. -M.; Bruntt, H.; Campante, T. L.;
   Corsaro, E.; Creevey, O. L.; Doğan, G.; Esch, L.; Gai, N.; Gaulme,
   P.; Hale, S. J.; Handberg, R.; Hekker, S.; Huber, D.; Jiménez, A.;
   Mathur, S.; Mazumdar, A.; Mosser, B.; New, R.; Pinsonneault, M. H.;
   Pricopi, D.; Quirion, P. -O.; Régulo, C.; Salabert, D.; Serenelli,
   A. M.; Silva Aguirre, V.; Sousa, S. G.; Stello, D.; Stevens, I. R.;
   Suran, M. D.; Uytterhoeven, K.; White, T. R.; Borucki, W. J.; Brown,
   T. M.; Jenkins, J. M.; Kinemuchi, K.; Van Cleve, J.; Klaus, T. C.
Bibcode: 2011Sci...332..213C
Altcode: 2011arXiv1109.4723C
  In addition to its search for extrasolar planets, the NASA Kepler
  mission provides exquisite data on stellar oscillations. We report the
  detections of oscillations in 500 solar-type stars in the Kepler field
  of view, an ensemble that is large enough to allow statistical studies
  of intrinsic stellar properties (such as mass, radius, and age) and
  to test theories of stellar evolution. We find that the distribution
  of observed masses of these stars shows intriguing differences to
  predictions from models of synthetic stellar populations in the Galaxy.

Title: Wave absorption and moat flow in AR9787
Authors: Roth, M.; Thompson, M. J.
Bibcode: 2011JPhCS.271a2022R
Altcode:
  We present the results of a study of the wave absorption and the moat
  flow around the sunspot in AR9787 (the "HELAS sunspot", so-called
  because it has been the object of in-depth study at a HELAS workshop)
  using Fourier-Hankel decomposition of the oscillatory wave field. We
  carry out inversions both for the flow speed and for the sound speed
  perturbation as a function of depth. The results are compared with
  results from time-distance helioseismology.

Title: Ring-analysis flow measurements of sunspot outflows
Authors: Featherstone, Nicholas A.; Hindman, Bradley W.; Thompson,
   Michael J.
Bibcode: 2011JPhCS.271a2002F
Altcode:
  We present a local helioseismological analysis of the convective
  flows around sunspots. The flow deductions were obtained from MDI
  Dopplergrams using ring-analysis techniques to measure Doppler
  shifts induced in solar acoustic oscillations. A novel multi-scale
  3-D inversion procedure was used to self-consistently combine all
  ring-analysis data taken from a mosaic of analysis tiles spanning the
  solar disk. The inversion is multi-scale because in addition to folding
  together information from tiles located at different positions on the
  solar surface, it is capable of incorporating tiles of different sizes,
  thus, enabling fine control of the horizontal resolution and the probing
  depth. The inversion is based on sensitivity kernels computed with
  the Born approximation. Our inversion results indicate that outflow
  observed at the surface surrounding sunspots persists to unexpectedly
  deep depths (~ 7 Mm). These outflows appear to have two components,
  being comprised of a superficial moat flow and a deeper outflow whose
  strength peaks around 5 Mm.

Title: First Global Rotation Inversions of HMI Data
Authors: Howe, R.; Larson, T. P.; Schou, J.; Hill, F.; Komm, R.;
   Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 2011JPhCS.271a2061H
Altcode:
  We present the first 2-dimensional global rotational inversions of
  medium-degree p-mode data from the Helioseismic and Magnetic Imager,
  and compare the results with inversions of Michelson Doppler Imager
  data for the same time period. The inferred rotation profiles show
  good agreement between the two instruments.

Title: Helioseismic Tests With the FLASH Simulation Code
Authors: González-Morales, Pedro A.; Jain, Rekha; Thompson, Michael J.
Bibcode: 2011JPhCS.271a2013G
Altcode:
  We show our first results from local helioseismic simulations using
  the numerical code FLASH by testing its suitability for simulating
  subphotospheric wave motions in helioseismology. In order to check
  the capability of this code for different sources of waves, we have
  implemented a non-magnetic plane-parallel atmosphere adding a source
  term to the energy equation. We confirm the capabilities of FLASH code
  for investigating the propagation of sound waves into a realistically
  stratified solar interior.

Title: Progress on the Baker Observatory Sub-minute Survey
Authors: Reed, Mike; Gilker, J.; Thompson, M.; Hicks, L.; Quint, A.;
   Metzger, A.
Bibcode: 2011AAS...21733408R
Altcode: 2011BAAS...4333408R
  The Baker Observatory Sub-minute Survey is designed to look for
  phenomena with short-period variability. Typical exposure times are
  under 15 seconds, surveying a magnitude range of 10-13 in white
  light. Known short-period phenomena include pulsating subdwarf B
  stars, white dwarfs, rapidly oscillating Ap stars and Delta Scuti
  stars. Currently, most sky surveys are interested in observing
  the entire sky and as such, the temporal cadence is best suited
  for variations of several hours or longer. Our survey observes
  single fields for four hour spans on two separate (non-adjacent)
  nights. During Phase I of our survey, we have selected 40 fields
  which contain at least one known variable star. It is then a blind
  study to determine if we can recover the known variable and search for
  new variables within each field. Observations for Phase I are nearly
  complete and we are enhancing our procedures and detection algorithms to
  optimize sensitivity to variations over many time scales. Our data are
  excellent for detecting variability shorter than two hours, even down
  to amplitudes of a millimagnitude (depending on S/N). This material
  is based upon work supported by the National Science Foundation under
  Grant No. Any opinions, findings, and conclusions or recommendations
  expressed in this material are those of the author(s) and do not
  necessarily reflect the views of the National Science Foundation. This
  work was partially funded by the Missouri Space Grant Consortium,
  funded by NASA and Missouri State University.

Title: The torsional oscillation and the new solar cycle
Authors: Howe, R.; Hill, F.; Komm, R.; Christensen-Dalsgaard, J.;
   Larson, T. P.; Schou, J.; Thompson, M. J.; Ulrich, R.
Bibcode: 2011JPhCS.271a2074H
Altcode:
  We present updated observations of the pattern of migrating solar
  zonal flows known as the torsional oscillation, covering 15 years of
  helioseismic measurements with GONG and MDI and 30 years of surface
  Doppler observations from Mount Wilson. We compare the behavior of the
  flows during the extended solar minimum following Cycle 23 with that in
  earlier minima. We demonstrate that the timing of the migration of the
  zonal flow belts may be of some use in predicting the start of the new
  cycle. We also note that the behavior of the high-latitude part of the
  pattern currently differs from that seen early in the previous cycle,
  with the high-latitude poleward-migrating branch still not established.

Title: Rotation-rate variations at the tachocline: An update
Authors: Howe, R.; Komm, R.; Hill, F.; Christensen-Dalsgaard, J.;
   Larson, T. P.; Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2011JPhCS.271a2075H
Altcode:
  After 15 years of GONG and MDI observations of the solar interior
  rotation, we revisit the issue of variations in the rotation rate near
  the base of the convection zone. The 1.3-year period seen in the first
  few years of the observations disappeared after 2000 and has still
  not returned. On the other hand, the agreement between GONG and MDI
  observations suggests that variations seen in this region have some
  solar origin, whether a true rotation-rate change or possibly mere
  stochastic variation; we present a numerical experiment supporting
  this contention.

Title: A new code for Fourier-Legendre analysis of large datasets:
    First results and a comparison with ring-diagram analysis
Authors: Doerr, H. -P.; Roth, M.; Zaatri, A.; Krieger, L.; Thompson,
   M. J.
Bibcode: 2010AN....331..911D
Altcode: 2010arXiv1011.4152D
  Fourier-Legendre decomposition (FLD) of solar Doppler imaging data is a
  promising method to estimate the sub-surface solar meridional flow. FLD
  is sensible to low-degree oscillation modes and thus has the potential
  to probe the deep meridional flow. We present a newly developed code to
  be used for large scale FLD analysis of helioseismic data as provided
  by the Global Oscillation Network Group (GONG), the Michelson Doppler
  Imager (MDI) instrument, and the upcoming Helioseismic and Magnetic
  Imager (HMI) instrument. First results obtained with the new code are
  qualitatively comparable to those obtained from ring-diagram analyis
  of the same time series.

Title: Asteroseismology of solar-type stars with Kepler I: Data
    analysis
Authors: Karoff, C.; Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.;
   Garcia, R. A.; Houdek, G.; Metcalfe, T. S.; Molenda-Żakowicz, J.;
   Monteiro, M. J. P. F. G.; Thompson, M. J.; Christensen-Dalsgaard, J.;
   Gilliland, R. L.; Kjeldsen, H.; Basu, S.; Bedding, T. R.; Campante,
   T. L.; Eggenberger, P.; Fletcher, S. T.; Gaulme, P.; Handberg, R.;
   Hekker, S.; Martic, M.; Mathur, S.; Mosser, B.; Regulo, C.; Roxburgh,
   I. W.; Salabert, D.; Stello, D.; Verner, G. A.; Belkacem, K.; Biazzo,
   K.; Cunha, M. S.; Gruberbauer, M.; Guzik, J. A.; Kupka, F.; Leroy,
   B.; Ludwig, H. -G.; Mathis, S.; Noels, A.; Noyes, R. W.; Roca Cortes,
   T.; Roth, M.; Sato, K. H.; Schmitt, J.; Suran, M. D.; Trampedach,
   R.; Uytterhoeven, K.; Ventura, R.
Bibcode: 2010AN....331..972K
Altcode: 2010arXiv1005.0507K
  We report on the first asteroseismic analysis of solar-type stars
  observed by Kepler. Observations of three G-type stars, 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 can clearly be distinguished
  in each star. We discuss the appearance of the oscillation spectra,
  including the presence of a possible signature of faculae, and the
  presence of mixed modes in one of the three stars.

Title: Four years of HELAS
Authors: Roth, M.; Lühe, O. v. d.; Aerts, C.; Christensen-Dalsgaard,
   J.; Corbard, T.; Daszyńska-Daszkiewicz, J.; Di Mauro, M. P.; Gizon,
   L.; Jiménez-Reyes, S.; Monteiro, M. J. P. F. G.; Pallé, P. L.;
   Thompson, M. J.
Bibcode: 2010AN....331.1084R
Altcode:
  The European Coordination Action on HELio- and ASteroseismology
  (HELAS) has completed its fourth and final year of initial funding by
  the European Commission. Set up as a network which combines solar and
  stellar physics communities in the important and vigorously evolving
  field of seismology, HELAS has been able to coordinate the efforts of
  European astronomers with remarkable success. Four large international
  conferences including the HELAS-IV conference on Lanzarote as well as
  many workshops were organized with a substantial contribution from
  HELAS. About a dozen workshops, addressing specialized questions in
  global and local helioseismology and asteroseismology were entirely
  organized by HELAS. Data analysis tools to prepare the European
  communities for the upcoming influx of data from new missions have
  been prepared, tested and demonstrated. Lecture notes and outreach
  material have been assembled and prepared for general access. As a
  result, HELAS has an important impact on the scientific output of the
  astrophysics seismology communities and significantly increased the
  visibility of European research in this field. This paper summarizes
  the activities and accomplishments of HELAS.

Title: Asteroseismology of solar-type stars with Kepler: II. Stellar
    modeling
Authors: Metcalfe, T. S.; Monteiro, M. J. P. F. G.; Thompson, M. J.;
   Chaplin, W. J.; Basu, S.; Bonanno, A.; Di Mauro, M. P.; Doğan, G.;
   Eggenberger, P.; Karoff, C.; Stello, D.; WG1, KASC
Bibcode: 2010AN....331..977M
Altcode: 2010arXiv1006.5695M
  Observations from the Kepler satellite were recently published for
  three bright G-type stars, which were monitored during the first 33.5
  days of science operations. One of these stars, KIC 11026764, exhibits
  a characteristic pattern of oscillation frequencies suggesting that the
  star has evolved significantly. We have derived initial estimates of the
  properties of KIC 11026764 from the oscillation frequencies observed
  by Kepler, combined with ground-based spectroscopic data. We present
  preliminary results from detailed modeling of this star, employing a
  variety of independent codes and analyses that attempt to match the
  asteroseismic and spectroscopic constraints simultaneously.

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: Modeling the Subsurface Structure of Sunspots
Authors: Moradi, H.; Baldner, C.; Birch, A. C.; Braun, D. C.; Cameron,
   R. H.; Duvall, T. L.; Gizon, L.; Haber, D.; Hanasoge, S. M.; Hindman,
   B. W.; Jackiewicz, J.; Khomenko, E.; Komm, R.; Rajaguru, P.; Rempel,
   M.; Roth, M.; Schlichenmaier, R.; Schunker, H.; Spruit, H. C.;
   Strassmeier, K. G.; Thompson, M. J.; Zharkov, S.
Bibcode: 2010SoPh..267....1M
Altcode: 2009arXiv0912.4982M; 2010SoPh..tmp..171M
  While sunspots are easily observed at the solar surface, determining
  their subsurface structure is not trivial. There are two main
  hypotheses for the subsurface structure of sunspots: the monolithic
  model and the cluster model. Local helioseismology is the only means
  by which we can investigate subphotospheric structure. However, as
  current linear inversion techniques do not yet allow helioseismology to
  probe the internal structure with sufficient confidence to distinguish
  between the monolith and cluster models, the development of physically
  realistic sunspot models are a priority for helioseismologists. This
  is because they are not only important indicators of the variety of
  physical effects that may influence helioseismic inferences in active
  regions, but they also enable detailed assessments of the validity of
  helioseismic interpretations through numerical forward modeling. In
  this article, we provide a critical review of the existing sunspot
  models and an overview of numerical methods employed to model wave
  propagation through model sunspots. We then carry out a helioseismic
  analysis of the sunspot in Active Region 9787 and address the serious
  inconsistencies uncovered by Gizon et al. (2009a, 2009b). We find that
  this sunspot is most probably associated with a shallow, positive
  wave-speed perturbation (unlike the traditional two-layer model)
  and that travel-time measurements are consistent with a horizontal
  outflow in the surrounding moat.

Title: Erratum: Erratum to: Helioseismology of Sunspots: A Case
    Study of NOAA Region 9787
Authors: Gizon, L.; Schunker, H.; Baldner, C. S.; Basu, S.; Birch,
   A. C.; Bogart, R. S.; Braun, D. C.; Cameron, R.; Duvall, T. L.;
   Hanasoge, S. M.; Jackiewicz, J.; Roth, M.; Stahn, T.; Thompson, M. J.;
   Zharkov, S.
Bibcode: 2010SSRv..156..257G
Altcode: 2010SSRv..tmp...99G
  No abstract at ADS

Title: VISTA Variables in the Vía Láctea (VVV): Current Status
    and First Results
Authors: Saito, R.; Hempel, M.; Alonso-García, J.; Toledo, I.;
   Borissova, J.; González, O.; Beamin, J. C.; Minniti, D.; Lucas, P.;
   Emerson, J.; Ahumada, A.; Aigrain, S.; Alonso, M. V.; Amôres, E.;
   Angeloni, R.; Arias, J.; Bandyopadhyay, R.; Barbá, R.; Barbuy, B.;
   Baume, G.; Bedin, L.; Bica, E.; Bronfman, L.; Carraro, G.; Catelan,
   M.; Clariá, J.; Contreras, C.; Cross, N.; Davis, C.; de Grijs, R.;
   Dékány, I.; Janet Drew, J. D.; Fariña, C.; Feinstein, C.; Fernández
   Lajús, E.; Folkes, S.; Gamen, R.; Geisler, D.; Gieren, W.; Goldman,
   B.; Gosling, A.; Gunthardt, G.; Gurovich, S.; Hambly, N.; Hanson, M.;
   Hoare, M.; Irwin, M.; Ivanov, V.; Jordán, A.; Kerins, E.; Kinemuchi,
   K.; Kurtev, R.; Longmore, A.; López-Corredoira, M.; Maccarone, T.;
   Martín, E.; Masetti, N.; Mennickent, R.; Merlo, D.; Messineo, M.;
   Mirabel, F.; Monaco, L.; Moni Bidin, C.; Morelli, L.; Padilla, N.;
   Palma, T.; Parisi, M. C.; Parker, Q.; Pavani, D.; Pietrukowicz, P.;
   Pietrzynski, G.; Pignata, G.; Rejkuba, M.; Rojas, A.; Roman Lopes,
   A.; Ruiz, M. T.; Sale, S.; Saviane, I.; Schreiber, M.; Schröder,
   A.; Sharma, S.; Smith, M.; Sodré, L., Jr.; Soto, M.; Stephens,
   A.; Tamura, M.; Tappert, C.; Thompson, M.; Valenti, E.; Vanzi, L.;
   Weidmann, W.; Zoccali, M.
Bibcode: 2010Msngr.141...24S
Altcode:
  VISTA Variables in the Vía Láctea (VVV) is a public ESO near-IR
  variability survey aimed at scanning the Milky Way Bulge and an adjacent
  section of the mid-plane. VVV observations started in October 2009
  during ESO science verification. Regular observations for the first
  year of the survey have been conducted since February 2010 and will
  cover a total area of 520 square degrees in five passbands and five
  epochs. Here we address the first results obtained from the VVV Survey
  as well as the current status of the observations.

Title: Herschel ATLAS: The cosmic star formation history of quasar
    host galaxies
Authors: Serjeant, S.; Bertoldi, F.; Blain, A. W.; Clements, D. L.;
   Cooray, A.; Danese, L.; Dunlop, J.; Dunne, L.; Eales, S.; Falder,
   J.; Hatziminaoglou, E.; Hughes, D. H.; Ibar, E.; Jarvis, M. J.;
   Lawrence, A.; Lee, M. G.; Michałowski, M.; Negrello, M.; Omont, A.;
   Page, M.; Pearson, C.; van der Werf, P. P.; White, G.; Amblard, A.;
   Auld, R.; Baes, M.; Bonfield, D. G.; Burgarella, D.; Buttiglione, S.;
   Cava, A.; Dariush, A.; de Zotti, G.; Dye, S.; Frayer, D.; Fritz, J.;
   Gonzalez-Nuevo, J.; Herranz, D.; Ivison, R. J.; Lagache, G.; Leeuw,
   L.; Lopez-Caniego, M.; Maddox, S.; Pascale, E.; Pohlen, M.; Rigby,
   E.; Rodighiero, G.; Samui, S.; Sibthorpe, B.; Smith, D. J. B.; Temi,
   P.; Thompson, M.; Valtchanov, I.; Verma, A.
Bibcode: 2010A&A...518L...7S
Altcode: 2010arXiv1005.2410S
  We present a derivation of the star formation rate per comoving volume
  of quasar host galaxies, derived from stacking analyses of far-infrared
  to mm-wave photometry of quasars with redshifts 0 &lt; z &lt; 6 and
  absolute I-band magnitudes -22 &gt; I<SUB>AB</SUB> &gt; -32 We use the
  science demonstration observations of the first ~16 deg<SUP>2</SUP>
  from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS)
  in which there are 240 quasars from the Sloan Digital Sky Survey (SDSS)
  and a further 171 from the 2dF-SDSS LRG and QSO (2SLAQ) survey. We
  supplement this data with a compilation of data from IRAS, ISO, Spitzer,
  SCUBA and MAMBO. H-ATLAS alone statistically detects the quasars in its
  survey area at &gt;5σ at 250,350 and 500 μm. From the compilation as
  a whole we find striking evidence of downsizing in quasar host galaxy
  formation: low-luminosity quasars with absolute magnitudes in the range
  -22 &gt; I<SUB>AB</SUB> &gt; -24 have a comoving star formation rate
  (derived from 100 μm rest-frame luminosities) peaking between redshifts
  of 1 and 2, while high-luminosity quasars with I<SUB>AB</SUB> &lt;
  -26 have a maximum contribution to the star formation density at z ~
  3. The volume-averaged star formation rate of -22 &gt; I<SUB>AB</SUB>
  &gt; -24 quasars evolves as (1 + z)<SUP>2.3±0.7</SUP> at z &lt; 2,
  but the evolution at higher luminosities is much faster reaching (1 +
  z)<SUP>10±1</SUP> at -26 &gt; I<SUB>AB</SUB> &gt; -28. We tentatively
  interpret this as a combination of a declining major merger rate with
  time and gas consumption reducing fuel for both black hole accretion
  and star formation. <P />Herschel is an ESA space observatory with
  science instruments provided by European-led Principal Investigator
  consortia with important participation from NASA.

Title: Herschel-ATLAS: The dust energy balance in the edge-on spiral
    galaxy UGC 4754
Authors: Baes, M.; Fritz, J.; Gadotti, D. A.; Smith, D. J. B.; Dunne,
   L.; da Cunha, E.; Amblard, A.; Auld, R.; Bendo, G. J.; Bonfield, D.;
   Burgarella, D.; Buttiglione, S.; Cava, A.; Clements, D.; Cooray,
   A.; Dariush, A.; de Zotti, G.; Dye, S.; Eales, S.; Frayer, D.;
   Gonzalez-Nuevo, J.; Herranz, D.; Ibar, E.; Ivison, R.; Lagache, G.;
   Leeuw, L.; Lopez-Caniego, M.; Jarvis, M.; Maddox, S.; Negrello, M.;
   Michałowski, M.; Pascale, E.; Pohlen, M.; Rigby, E.; Rodighiero,
   G.; Samui, S.; Serjeant, S.; Temi, P.; Thompson, M.; van der Werf,
   P.; Verma, A.; Vlahakis, C.
Bibcode: 2010A&A...518L..39B
Altcode: 2010arXiv1005.1773B
  We use Herschel PACS and SPIRE observations of the edge-on spiral galaxy
  UGC 4754, taken as part of the H-ATLAS SDP observations, to investigate
  the dust energy balance in this galaxy. We build detailed SKIRT
  radiative models based on SDSS and UKIDSS maps and use these models to
  predict the far-infrared emission. We find that our radiative transfer
  model underestimates the observed FIR emission by a factor of two to
  three. Similar discrepancies have been found for other edge-on spiral
  galaxies based on IRAS, ISO, and SCUBA data. Thanks to the good sampling
  of the SED at FIR wavelengths, we can rule out an underestimation of the
  FIR emissivity as the cause for this discrepancy. Instead we support
  highly obscured star formation that contributes little to the optical
  extinction as a more probable explanation. <P />Herschel is an ESA space
  observatory with science instruments provided by European-led principal-
  investigator consortia and with important participation from NASA.

Title: Herschel-ATLAS: Extragalactic number counts from 250 to
    500 microns
Authors: Clements, D. L.; Rigby, E.; Maddox, S.; Dunne, L.; Mortier,
   A.; Pearson, C.; Amblard, A.; Auld, R.; Baes, M.; Bonfield, D.;
   Burgarella, D.; Buttiglione, S.; Cava, A.; Cooray, A.; Dariush, A.;
   de Zotti, G.; Dye, S.; Eales, S.; Frayer, D.; Fritz, J.; Gardner,
   Jonathan P.; Gonzalez-Nuevo, J.; Herranz, D.; Ibar, E.; Ivison, R.;
   Jarvis, M. J.; Lagache, G.; Leeuw, L.; Lopez-Caniego, M.; Negrello,
   M.; Pascale, E.; Pohlen, M.; Rodighiero, G.; Samui, S.; Serjeant,
   S.; Sibthorpe, B.; Scott, D.; Smith, D. J. B.; Temi, P.; Thompson,
   M.; Valtchanov, I.; van der Werf, P.; Verma, A.
Bibcode: 2010A&A...518L...8C
Altcode: 2010arXiv1005.2409C
  <BR /> Aims: The Herschel-ATLAS survey (H-ATLAS) will be the largest
  area survey to be undertaken by the Herschel Space Observatory. It
  will cover 550 sq. deg. of extragalactic sky at wavelengths of 100,
  160, 250, 350 and 500 μm when completed, reaching flux limits (5σ)
  from 32 to 145 mJy. We here present galaxy number counts obtained
  for SPIRE observations of the first ~14 sq. deg. observed at 250,
  350 and 500 μm. <BR /> Methods: Number counts are a fundamental
  tool in constraining models of galaxy evolution. We use source
  catalogs extracted from the H-ATLAS maps as the basis for such an
  analysis. Correction factors for completeness and flux boosting are
  derived by applying our extraction method to model catalogs and then
  applied to the raw observational counts. <BR /> Results: We find a
  steep rise in the number counts at flux levels of 100-200 mJy in all
  three SPIRE bands, consistent with results from BLAST. The counts are
  compared to a range of galaxy evolution models. None of the current
  models is an ideal fit to the data but all ascribe the steep rise to a
  population of luminous, rapidly evolving dusty galaxies at moderate to
  high redshift. <P />Herschel is an ESA space observatory with science
  instruments provided by European-led Principal Investigator consortia
  and with important participation from NASA.

Title: Herschel-ATLAS: Blazars in the science demonstration phase
    field
Authors: González-Nuevo, J.; de Zotti, G.; Andreani, P.; Barton,
   E. J.; Bertoldi, F.; Birkinshaw, M.; Bonavera, L.; Buttiglione, S.;
   Cooke, J.; Cooray, A.; Danese, G.; Dunne, L.; Eales, S.; Fan, L.;
   Jarvis, M. J.; Klöckner, H. -R.; Hatziminaoglou, E.; Herranz, D.;
   Hughes, D. H.; Lapi, A.; Lawrence, A.; Leeuw, L.; Lopez-Caniego, M.;
   Massardi, M.; Mauch, T.; Michałowski, M. J.; Negrello, M.; Rawlings,
   S.; Rodighiero, G.; Samui, S.; Serjeant, S.; Vieira, J. D.; White,
   G.; Amblard, A.; Auld, R.; Baes, M.; Bonfield, D. G.; Burgarella, D.;
   Cava, A.; Clements, D. L.; Dariush, A.; Dye, S.; Frayer, D.; Fritz,
   J.; Ibar, E.; Ivison, R. J.; Lagache, G.; Maddox, S.; Pascale, E.;
   Pohlen, M.; Rigby, E.; Sibthorpe, B.; Smith, D. J. B.; Temi, P.;
   Thompson, M.; Valtchanov, I.; Verma, A.
Bibcode: 2010A&A...518L..38G
Altcode: 2010arXiv1005.2407G
  To investigate the poorly constrained sub-mm counts and spectral
  properties of blazars we searched for these in the Herschel-ATLAS
  (H-ATLAS) science demonstration phase (SDP) survey catalog. We
  cross-matched 500 μm sources brighter than 50 mJy with the FIRST radio
  catalogue. We found two blazars, both previously known. Our study is
  among the first blind blazar searches at sub-mm wavelengths, i.e.,
  in the spectral regime where little is still known about the blazar
  SEDs, but where the synchrotron peak of the most luminous blazars
  is expected to occur. Our early results are consistent with educated
  extrapolations of lower frequency counts and question indications of
  substantial spectral curvature downwards and of spectral upturns at
  mm wavelengths. One of the two blazars is identified with a Fermi/LAT
  γ-ray source and a WMAP source. The physical parameters of the two
  blazars are briefly discussed. These observations demonstrate that the
  H-ATLAS survey will provide key information about the physics of blazars
  and their contribution to sub-mm counts. <P />Herschel is an ESA space
  observatory with science instruments provided by European-led Principal
  Investigator consortia and with important participation from NASA.

Title: Herschel-ATLAS: The angular correlation function of
    submillimetre galaxies at high and low redshift
Authors: Maddox, S. J.; Dunne, L.; Rigby, E.; Eales, S.; Cooray, A.;
   Scott, D.; Peacock, J. A.; Negrello, M.; Smith, D. J. B.; Benford,
   D.; Amblard, A.; Auld, R.; Baes, M.; Bonfield, D.; Burgarella, D.;
   Buttiglione, S.; Cava, A.; Clements, D.; Dariush, A.; de Zotti, G.;
   Dye, S.; Frayer, D.; Fritz, J.; Gonzalez-Nuevo, J.; Herranz, D.; Ibar,
   E.; Ivison, R.; Jarvis, M. J.; Lagache, G.; Leeuw, L.; Lopez-Caniego,
   M.; Pascale, E.; Pohlen, M.; Rodighiero, G.; Samui, S.; Serjeant,
   S.; Temi, P.; Thompson, M.; Verma, A.
Bibcode: 2010A&A...518L..11M
Altcode: 2010arXiv1005.2406M
  We present measurements of the angular correlation function of galaxies
  selected from the first field of the H-ATLAS survey. Careful removal
  of the background from galactic cirrus is essential, and currently
  dominates the uncertainty in our measurements. For our 250 μm-selected
  sample we detect no significant clustering, consistent with the
  expectation that the 250 μm-selected sources are mostly normal
  galaxies at z ⪉ 1. For our 350 μm and 500 μm-selected samples
  we detect relatively strong clustering with correlation amplitudes
  A of 0.2 and 1.2 at 1', but with relatively large uncertainties. For
  samples which preferentially select high redshift galaxies at z~2-3
  we detect significant strong clustering, leading to an estimate of
  r<SUB>0</SUB> ~ 7-11 h<SUP>-1</SUP> Mpc. The slope of our clustering
  measurements is very steep, δ ~ 2. The measurements are consistent
  with the idea that sub-mm sources consist of a low redshift population
  of normal galaxies and a high redshift population of highly clustered
  star-bursting galaxies. <P />Herschel is an ESA space observatory with
  science instruments provided by European-led Principal Investigator
  consortia and with important participation from NASA.

Title: OT1_mthomp01_1: Confirming a sample of luminous debris disk
    candidates identified in the Herschel ATLAS
Authors: Thompson, M.
Bibcode: 2010hers.prop.1318T
Altcode:
  Debris disks are the remains of planetary system formation, tracing
  the existence of planetesimal-sized objects in orbit around main
  sequence stars. Current and planned surveys of debris disks (including
  the Herschel Key Projects DEBRIS and DUNES) are deep surveys aimed
  at characterising the typical population of disks and targeted at
  samples of a few hundred nearby objects. These deep narrow surveys are
  relatively insensitive to the rarities in the debris disk population,
  some of which may be luminous and/or massive disks that have undergone
  recent disruptive collisional events. We have recently shown that the
  primarily extragalactic Key Project, the Herschel-ATLAS, can be used as
  a wide and shallow survey of debris disks by combining its excellent
  optical coverage and statistical techniques more commonly employed to
  identify galaxies. The combination of Herschel-ATLAS, DEBRIS and DUNES
  thus forms a powerful nested tier of surveys that will be sensitive
  to disks across the spectrum from exosolar analogues to rare disks
  that cannot be inferred from local populations. In this proposal we
  seek time to image the three candidate disks that we discovered in
  the Herschel-ATLAS Science Demonstration Phase with PACS so that we
  may confirm them as true debris disks and model their SEDs to extract
  mass, temperature and fractional luminosity. We will confirm whether
  these disk candidates are in fact the most luminous disks yet detected.

Title: Helioseismology over the Solar Cycle
Authors: Thompson, M. J.
Bibcode: 2010ASPC..428...23T
Altcode: 2010arXiv1003.3888T
  Helioseismology has produced unprecedented measurements of the Sun's
  internal structure and dynamics over the past 25 years. Much of this
  work has been based on global helioseismology. Now local helioseismology
  too is showing its great promise. This review summarizes very briefly
  the principal global results that may be relevant to an understanding of
  the origins of solar magnetism. Recent results regarding the variation
  of frequencies over the solar cycle and the temporal variations of
  subsurface flows are briefly summarized.

Title: Developing Physics-Based Procedures for Local Helioseismic
    Probing of Sunspots and Magnetic Regions
Authors: Birch, Aaron; Braun, D. C.; Crouch, A.; Rempel, M.; Fan,
   Y.; Centeno, R.; Toomre, J.; Haber, D.; Hindman, B.; Featherstone,
   N.; Duvall, T., Jr.; Jackiewicz, J.; Thompson, M.; Stein, R.; Gizon,
   L.; Cameron, R.; Saidi, Y.; Hanasoge, S.; Burston, R.; Schunker, H.;
   Moradi, H.
Bibcode: 2010AAS...21630805B
Altcode:
  We have initiated a project to test and improve the local helioseismic
  techniques of time-distance and ring-diagram analysis. Our goals are
  to develop and implement physics-based methods that will (1) enable the
  reliable determinations of subsurface flow, magnetic field, and thermal
  structure in regions of strong magnetic fields and (2) be quantitatively
  tested with realistic solar magnetoconvection simulations in the
  presence of sunspot-like magnetic fields. We are proceeding through a
  combination of improvements in local helioseismic measurements, forward
  modeling of the helioseismic wavefield, kernel computations, inversions,
  and validation through numerical simulations. As improvements over
  existing techniques are made they will be applied to the SDO/HMI
  observations. This work is funded through the the NASA Heliophysics
  Science Division through the Solar Dynamics Observatory (SDO) Science
  Center program.

Title: The Solar Dynamo
Authors: Jones, Chris A.; Thompson, Michael J.; Tobias, Steven M.
Bibcode: 2010SSRv..152..591J
Altcode:
  Observations relevant to current models of the solar dynamo are
  presented, with emphasis on the history of solar magnetic activity
  and on the location and nature of the solar tachocline. The problems
  encountered when direct numerical simulation is used to analyse the
  solar cycle are discussed, and recent progress is reviewed. Mean field
  dynamo theory is still the basis of most theories of the solar dynamo,
  so a discussion of its fundamental principles and its underlying
  assumptions is given. The role of magnetic helicity is discussed. Some
  of the most popular models based on mean field theory are reviewed
  briefly. Dynamo models based on severe truncations of the full MHD
  equations are discussed.

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: The Smallest Lunar Grains: Analytical TEM Characterization
    of the Sub-Micron Size Fraction of a Mare Soil
Authors: Thompson, M.; Christoffersen, R.
Bibcode: 2010LPI....41.2191T
Altcode:
  Analytical TEM observations show the sub-micron size fraction of
  a mature mare soil is highly enriched in glass grains, including
  spherules, relative to the larger size fractions, including the sub
  10 micron size fraction as a whole.

Title: The Solar Dynamo
Authors: Jones, Chris A.; Thompson, Michael J.; Tobias, Steven M.
Bibcode: 2010plma.book..591J
Altcode:
  No abstract at ADS

Title: Baker Observatory Subminute Survey
Authors: Gilker, Justin; Reed, M.; Doennig, A.; Quint, A.; Hicks,
   L.; Thompson, M.
Bibcode: 2010AAS...21541805G
Altcode: 2010BAAS...42..275G
  We are conducting a small-scale short-period stellar variability
  survey using our 16-inch telescope at Baker Observatory. The goal is
  to search for previously undetected variability types and to increase
  membership of known pulsation classes. We are currently in the first
  portion of this survey which is to understand the sensitivity of
  our observations. Our strategy is to have four hour runs with short
  integrations and observe each field twice. We have begun collecting
  data with at least one known type of variable star in each field
  and are doing a blind study to recover the known variable and seek
  new variable stars. Our initial strategy for detecting variability
  is to use Fourier techniques for short-period (1 - 30 minutes)
  variability, phase-dispersion techniques for mid-period (0.5 to 4
  hours) and a brightness comparator between the runs for long-period
  (4 hours to days) variations. <P />This research is sponsored by the
  National Science Foundation grant 0913175 and The Missouri Space Grant
  Consortium, funded by NASA. Any opinions, findings, and conclusions
  or recommendations expressed in this material are those of the authors
  and do not necessarily reflect views of the National Science Foundation.

Title: Analysis of Acoustic Wave Propagation in the Subphotosphere
    with Localized Magnetic Field Concentration
Authors: Zharkov, S.; Shelyag, S.; Thompson, M. J.
Bibcode: 2009ASPC..416...75Z
Altcode:
  We present the time-distance analysis of numerical simulations of
  acoustic wave propagation and dispersion in the solar subphotosphere
  with a localized magnetic field concentration.

Title: Iterative Inversion for Solar and Stellar Internal Rotation
Authors: Sudnik, M.; Thompson, M. J.
Bibcode: 2009ASPC..416..411S
Altcode:
  We investigate the feasibility and efficiency of using an iterative
  method used in geophysics for solving the inverse problem of inferring
  from frequency splittings the internal rotation of the Sun or other
  stars.

Title: The internal dynamics and magnetism of the sun -- the
    perspective from global helioseismology (Invited)
Authors: Howe, R.; Hill, F.; Komm, R.; Christensen-Dalsgaard, J.;
   Schou, J.; Thompson, M. J.
Bibcode: 2009AGUFMSH11B..04H
Altcode:
  Helioseismology allows us to probe the interior dynamics of the
  Sun. Observations over the past three decades reveal the interior
  rotation profile, with a near-surface shear layer, differential
  rotation throughout the convection zone, a strong shear layer -- the
  tachocline -- at the base of the convection zone, and approximately
  uniform rotation in the radiative interior. Since the mid 1990's,
  continuous observations from the Global Oscillations Network Group and
  the Michelson Doppler Imager have allowed the study of subtle temporal
  variations in the rotation within the convection zone. The so-called
  "torsional oscillation" pattern of migrating zonal flows accompanying
  the surface activity migration during the solar cycle has been shown to
  penetrate deep within the convection zone. During the current extended
  solar minimum, the flow bands can be seen to migrate more slowly towards
  the equator than was seen in the previous minimum. There have also been
  (still unconfirmed) findings of shorter-term variations in the rotation
  rate close to the tachocline during the early years of the previous
  solar cycle. This review will describe the important results and give
  an update on the most recent observations of the interior dynamics as
  we await the rise of solar cycle 24.

Title: The Herschel ATLAS Key Project
Authors: Serjeant, S.; Eales, S.; Dunne, L.; Clements, D.; Cooray, A.;
   de Zotti, G.; Dye, S.; Ivison, R.; Jarvis, M.; Lagache, G.; Maddox,
   S.; Negrello, M.; Thompson, M.; Herschel Atlas Consortium
Bibcode: 2009ASPC..418..523S
Altcode:
  The Herschel Astrophysical Terahertz Large Area Survey (ATLAS) is the
  largest Open Time Key Project on the Herschel Space Observatory. This
  legacy survey will cover 550 deg<SUP>2</SUP>, an order of magnitude
  larger than all other Herschel extragalactic surveys combined, and
  will provide more extragalactic sources than all other Herschel
  surveys combined. Herschel ATLAS builds on the ground-breaking
  AKARI All-Sky Survey and has six primary science themes, described
  here. More information can be found on the consortium web site,
  http://h-atlas.astro.cf.ac.uk .

Title: Numerical Simulation of Acoustic Wave Propagation in the
    Solar Sub-Photosphere with Localized Magnetic Field Concentration
Authors: Shelyag, S.; Zharkov, S.; Fedun, V.; Erdélyi, R.; Thompson,
   M. J.
Bibcode: 2009ASPC..416..167S
Altcode:
  The results of numerical simulations of acoustic wave propagation and
  dispersion in the solar sub-photosphere with a localised magnetic
  field concentration are presented. The initial equilibrium density
  and pressure stratifications are derived from a standard solar
  model and adjusted to maintain magnetohydrostatic and convective
  stability. Acoustic waves are generated by a perturbation located
  at the height corresponding to the visible surface of the Sun. The
  time-distance diagram of the vertical velocity perturbation at the level
  corresponding to the visible solar surface shows that the magnetic
  field perturbs and scatters acoustic waves and absorbs the acoustic
  power of the wave packet.

Title: The Torsional Oscillation and the Solar Minimum
Authors: Howe, R.; Hill, F.; Komm, R.; Christensen-Dalsgaard, J.;
   Schou, J.; Thompson, M. J.
Bibcode: 2009AGUFM.U34A..03H
Altcode:
  The so-called torsional oscillation is a pattern of zonal flow bands,
  detected at the solar surface by direct Doppler measurements and within
  the convection zone by helioseismic measurements such as those carried
  out by the Global Oscillations Network Group and the Michelson Doppler
  Imager, that migrates from mid-latitudes towards the equator and poles
  with each solar cycle. In the current minimum the low-latitude branch
  of the pattern can be seen to have taken at least a year longer to
  migrate towards the equator than was the case in the previous minimum. A
  flow configuration matching that of the previous minimum was reached
  during 2008, and by early 2009 the fast-rotating belt associated with
  the new cycle had reached the latitude at which the onset of activity
  was seen in Cycle 23, but magnetic activity has remained low. We will
  present the most recent results and consider the implications for the
  new solar cycle.

Title: The Torsional Oscillation and the Solar Cycle: Is it Minimum
    Yet?
Authors: Howe, R.; Komm, R.; Hill, F.; Larson, T.; Schou, J.; Thompson,
   M. J.; Ulrich, R. K.
Bibcode: 2009ASPC..416..269H
Altcode:
  The torsional oscillation pattern of migrating zonal flows is related to
  the solar activity cycle. In the approach to solar minimum, we compare
  the current flow profile with that seen at the previous minimum, using
  Global Oscillation Network Group (GONG) and Michelson Doppler Imager
  (MDI) data as well as Mount Wilson Doppler observations that reach
  further back in time. Will the flow pattern at the upcoming minimum
  match that for the previous one?

Title: Mode identification in rapidly rotating stars
Authors: Reese, D. R.; Thompson, M. J.; MacGregor, K. B.; Jackson,
   S.; Skumanich, A.; Metcalfe, T. S.
Bibcode: 2009A&A...506..183R
Altcode: 2009arXiv0905.4889R
  Context: Recent calculations of pulsation modes in rapidly rotating
  polytropic models and models based on the Self-Consistent Field method
  have shown that the frequency spectrum of low degree pulsation modes can
  be described by an empirical formula similar to Tassoul's asymptotic
  formula, provided that the underlying rotation profile is not too
  differential. <BR />Aims: Given the simplicity of this asymptotic
  formula, we investigate whether it can provide a means by which to
  identify pulsation modes in rapidly rotating stars. <BR />Methods:
  We develop a new mode identification scheme which consists in scanning
  a multidimensional parameter space for the formula coefficients which
  yield the best-fitting asymptotic spectra. This mode identification
  scheme is then tested on artificial spectra based on the asymptotic
  formula, on random frequencies and on spectra based on full numerical
  eigenmode calculations for which the mode identification is known
  beforehand. We also investigate the effects of adding random frequencies
  to mimic the effects of chaotic modes which are also expected to show
  up in such stars. <BR />Results: In the absence of chaotic modes,
  it is possible to accurately find a correct mode identification
  for most of the observed frequencies provided these frequencies are
  sufficiently close to their asymptotic values. The addition of random
  frequencies can very quickly become problematic and hinder correct mode
  identification. Modifying the mode identification scheme to reject the
  worst fitting modes can bring some improvement but the results still
  remain poorer than in the case without chaotic modes.

Title: Photospheric high-frequency acoustic power excess in sunspot
umbra: signature of magneto-acoustic modes
Authors: Zharkov, S.; Shelyag, S.; Fedun, V.; Erdélyi, R.; Thompson,
   M. J.
Bibcode: 2009arXiv0909.5332Z
Altcode:
  We present observational evidence for the presence of MHD waves in
  the solar photosphere deduced from SOHO/MDI Dopplergram velocity
  observations. The magneto-acoustic perturbations are observed as
  acoustic power enhancement in the sunspot umbra at high-frequency bands
  in the velocity component perpendicular to the magnetic field. We use
  numerical modelling of wave propagation through localised non-uniform
  magnetic field concentration along with the same filtering procedure
  as applied to the observations to identify the observed waves. Guided
  by the results of the numerical simulations we classify the observed
  oscillations as magneto-acoustic waves excited by the trapped
  sub-photospheric acoustic waves. We consider the potential application
  of the presented method as a diagnostic tool for magnetohelioseismology.

Title: A Note on the Torsional Oscillation at Solar Minimum
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R.;
   Schou, J.; Thompson, M. J.
Bibcode: 2009ApJ...701L..87H
Altcode: 2009arXiv0907.2965H
  We examine the evolution of the zonal flow pattern in the upper solar
  convection zone during the current extended solar minimum, and compare
  it with that during the previous minimum. The results suggest that
  a configuration matching that at the previous minimum was reached
  during 2008, but that the flow band corresponding to the new cycle has
  been moving more slowly toward the equator than was observed in the
  previous cycle, resulting in a gradual increase in the apparent length
  of the cycle during the 2007-2008 period. The current position of the
  lower-latitude fast-rotating belt corresponds to that seen around the
  onset of activity in the previous cycle.

Title: Acoustic wave propagation in the solar sub-photosphere with
localised magnetic field concentration: effect of magnetic tension
Authors: Shelyag, S.; Zharkov, S.; Fedun, V.; Erdélyi, R.; Thompson,
   M. J.
Bibcode: 2009A&A...501..735S
Altcode: 2009arXiv0901.3680S
  Aims: We analyse numerically the propagation and dispersion of acoustic
  waves in the solar-like sub-photosphere with localised non-uniform
  magnetic field concentrations, mimicking sunspots with various
  representative magnetic field configurations. <BR />Methods: Numerical
  simulations of wave propagation through the solar sub-photosphere
  with a localised magnetic field concentration are carried out using
  SAC, which solves the MHD equations for gravitationally stratified
  plasma. The initial equilibrium density and pressure stratifications
  are derived from a standard solar model. Acoustic waves are generated
  by a source located at the height corresponding approximately to
  the visible surface of the Sun. By means of local helioseismology we
  analyse the response of vertical velocity at the level corresponding
  to the visible solar surface to changes induced by magnetic field in
  the interior. <BR />Results: The results of numerical simulations of
  acoustic wave propagation and dispersion in the solar sub-photosphere
  with localised magnetic field concentrations of various types are
  presented. Time-distance diagrams of the vertical velocity perturbation
  at the level corresponding to the visible solar surface show that the
  magnetic field perturbs and scatters acoustic waves and absorbs the
  acoustic power of the wave packet. For the weakly magnetised case, the
  effect of magnetic field is mainly thermodynamic, since the magnetic
  field changes the temperature stratification. However, we observe
  the signature of slow magnetoacoustic mode, propagating downwards,
  for the strong magnetic field cases.

Title: VISTA Milky Way Public Survey
Authors: Minniti, D.; Lucas, P.; Ahumada, A. V.; Zoccali, M.; Catelan,
   M.; Morelli, L.; Tappert, C.; Pignata, G.; Toledo, I.; Ruiz, M. T.;
   Carraro, G.; Casassus, S.; Bronfman, L.; Barbá, R. H.; Gamen, R.;
   Gieren, W.; Geisler, D.; Pietrzynski, G.; Mennickent, R. E.; Kurtev,
   R.; Borissova, J.; Mirabel, F.; Ivanov, V. D.; Saviane, I.; Vanzi, L.;
   Monaco, L.; Rejkuba, M.; Messineo, M.; Bedin, L.; Stephens, A.; Barbuy,
   B.; Bica, E.; Clariá, J. J.; CASU (VDFS) Team; WFAU (VDFS) Team;
   Emerson, J.; Drew, J.; López-Correidora, M.; Martin, E.; Goldman,
   B.; Gianinni, T.; Eisloeffel, J.; Groot, P.; Fabregat, J.; Hambly,
   N.; Longmore, A.; Walton, N.; de Grijs, R.; Hoare, M.; Schroeder,
   A.; Naylor, T.; Barlow, M.; Zijlstra, A.; White, G.; Gosling, A.;
   McGowan, K.; Adamson, A.; Bandyopadhyay, R.; Thompson, M.; Cropper,
   M.; Lucey, J.; Kerins, E.; Hodgkin, S.; Pinfield, D.
Bibcode: 2009RMxAC..35..263M
Altcode:
  We propose a public IR variability survey, named ``Vista Variables
  in the Vía Láctea'' (VVV), of the Milky Way bulge and an adjacent
  section of the mid-plane where star formation activity is high. This
  would take 1920 hours, covering ∼ 10^9 point sources within an area
  of 520 sq deg, including 33 known globular clusters and ∼ 350 open
  clusters. The final products will be a deep IR atlas in 5 passbands and
  a catalogue of ∼ 10^6 variable point sources. These will produce a
  3-D map of the surveyed region (unlike single-epoch surveys that only
  give 2-D maps) using well-understood primary distance indicators such
  as RR Lyrae stars. It will yield important information on the ages
  of the populations. The observations will be combined with data from
  MACHO, OGLE, EROS, VST, SPITZER, HST, CHANDRA, INTEGRAL, and ALMA for
  a complete understanding of the variable sources in the inner Milky
  Way. Several important implications for the history of the Milky Way,
  for globular cluster evolution, for the population census of the bulge
  and center, and for pulsation theory would follow from this survey.

Title: Helioseismology of Sunspots: A Case Study of NOAA Region 9787
Authors: Gizon, L.; Schunker, H.; Baldner, C. S.; Basu, S.; Birch,
   A. C.; Bogart, R. S.; Braun, D. C.; Cameron, R.; Duvall, T. L.;
   Hanasoge, S. M.; Jackiewicz, J.; Roth, M.; Stahn, T.; Thompson, M. J.;
   Zharkov, S.
Bibcode: 2009SSRv..144..249G
Altcode: 2008SSRv..tmp..188G; 2010arXiv1002.2369G
  Various methods of helioseismology are used to study the subsurface
  properties of the sunspot in NOAA Active Region 9787. This sunspot
  was chosen because it is axisymmetric, shows little evolution during
  20-28 January 2002, and was observed continuously by the MDI/SOHO
  instrument. AR 9787 is visible on helioseismic maps of the farside
  of the Sun from 15 January, i.e. days before it crossed the East
  limb. Oscillations have reduced amplitudes in the sunspot at all
  frequencies, whereas a region of enhanced acoustic power above 5.5 mHz
  (above the quiet-Sun acoustic cutoff) is seen outside the sunspot and
  the plage region. This enhanced acoustic power has been suggested to
  be caused by the conversion of acoustic waves into magneto-acoustic
  waves that are refracted back into the interior and re-emerge as
  acoustic waves in the quiet Sun. Observations show that the sunspot
  absorbs a significant fraction of the incoming p and f modes around 3
  mHz. A numerical simulation of MHD wave propagation through a simple
  model of AR 9787 confirmed that wave absorption is likely to be due
  to the partial conversion of incoming waves into magneto-acoustic
  waves that propagate down the sunspot. Wave travel times and mode
  frequencies are affected by the sunspot. In most cases, wave packets
  that propagate through the sunspot have reduced travel times. At
  short travel distances, however, the sign of the travel-time shifts
  appears to depend sensitively on how the data are processed and,
  in particular, on filtering in frequency-wavenumber space. We carry
  out two linear inversions for wave speed: one using travel-times
  and phase-speed filters and the other one using mode frequencies
  from ring analysis. These two inversions give subsurface wave-speed
  profiles with opposite signs and different amplitudes. The travel-time
  measurements also imply different subsurface flow patterns in the
  surface layer depending on the filtering procedure that is used. Current
  sensitivity kernels are unable to reconcile these measurements, perhaps
  because they rely on imperfect models of the power spectrum of solar
  oscillations. We present a linear inversion for flows of ridge-filtered
  travel times. This inversion shows a horizontal outflow in the upper
  4 Mm that is consistent with the moat flow deduced from the surface
  motion of moving magnetic features. From this study of AR 9787, we
  conclude that we are currently unable to provide a unified description
  of the subsurface structure and dynamics of the sunspot.

Title: The Solar Dynamo
Authors: Weiss, N. O.; Thompson, M. J.
Bibcode: 2009SSRv..144...53W
Altcode: 2008SSRv..tmp..155W
  It is generally accepted that the strong toroidal magnetic fields that
  emerge through the solar surface in sunspots and active regions are
  formed by the action of differential rotation on a poloidal field,
  and then stored in or near the tachocline at the base of the Sun’s
  convection zone. The problem is how to explain the generation of
  a reversed poloidal field from this toroidal flux—a process that
  can be parametrised in terms of an α-effect related to some form
  of turbulent helicity. Here we first outline the principal patterns
  that have to be explained: the 11-year activity cycle, the 22-year
  magnetic cycle and the longer term modulation of cyclic activity,
  associated with grand maxima and minima. Then we summarise what has
  been learnt from helioseismology about the Sun’s internal structure
  and rotation that may be relevant to our subject. The ingredients
  of mean-field dynamo models are differential rotation, meridional
  circulation, turbulent diffusion, flux pumping and the α-effect:
  in various combinations they can reproduce the principal features
  that are observed. To proceed further, it is necessary to rely on
  large-scale computation and we summarise the current state of play.

Title: Introduction to Solar Magnetism: The Early Years
Authors: Balogh, A.; Thompson, M. J.
Bibcode: 2009SSRv..144....1B
Altcode:
  The year 2008 marked the one hundredth anniversary of the observational
  discovery by George Ellery Hale of magnetic field in sunspots (Hale
  in Astrophys. J. 28:315-343, 1908). This observation, the first to
  suggest a direct link between the best-known variable features on
  the Sun and magnetism, started a line of research that has widened
  considerably over the last 100 years and is continuing today. Knowledge
  about all aspects of the Sun has increased in a remarkable way over
  the past few decades. Variations in the appearance of the Sun and its
  corona, as well as deeper sources of quasi-regular and chaotic changes
  that make up solar variability have been extensively documented by
  both ground-based and space-based solar observatories. It has been
  recognized that solar magnetism is the key phenomenon that drives
  solar variability. The workshop devoted to the origin and dynamics of
  solar magnetism held in the International Space Science Institute in
  Bern, Switzerland, from 21 to 25 January 2008 reviewed the status of
  the field and has led to this volume that brings together the best
  available knowledge and understanding of solar magnetism 100 years
  after Hale’s pioneering paper. This introductory paper gives an
  outline of the history of research into solar variability up to the
  work of Hale and his colleagues. The achievements of the past decades
  are discussed extensively in the other contributions to this volume.

Title: Introduction to Solar Magnetism: The Early Years
Authors: Balogh, A.; Thompson, M. J.
Bibcode: 2009odsm.book....1B
Altcode:
  The year 2008 marked the one hundredth anniversary of the observational
  discovery by George Ellery Hale of magnetic field in sunspots (Hale
  in Astrophys. J. 28:315-343, 1908). This observation, the first to
  suggest a direct link between the best-known variable features on
  the Sun and magnetism, started a line of research that has widened
  considerably over the last 100 years and is continuing today. Knowledge
  about all aspects of the Sun has increased in a remarkable way over
  the past few decades. Variations in the appearance of the Sun and its
  corona, as well as deeper sources of quasi-regular and chaotic changes
  that make up solar variability have been extensively documented by
  both ground-based and space-based solar observatories. It has been
  recognized that solar magnetism is the key phenomenon that drives
  solar variability. The workshop devoted to the origin and dynamics
  of solar magnetism held in the International Space Science Institute
  in Bern, Switzerland, from 21 to 25 January 2008 reviewed the status
  of the field and has led to this volume that brings together the best
  available knowledge and understanding of solar magnetism 100 years after
  Hale's pioneering paper. This introductory paper gives an outline of
  the history of research into solar variability up to the work of Hale
  and his colleagues. The achievements of the past decades are discussed
  extensively in the other contributions to this volume.

Title: The Solar Dynamo
Authors: Weiss, N. O.; Thompson, M. J.
Bibcode: 2009odsm.book...53W
Altcode:
  It is generally accepted that the strong toroidal magnetic fields that
  emerge through the solar surface in sunspots and active regions are
  formed by the action of differential rotation on a poloidal field,
  and then stored in or near the tachocline at the base of the Sun's
  convection zone. The problem is how to explain the generation of
  a reversed poloidal field from this toroidal flux—a process that
  can be parametrised in terms of an α-effect related to some form
  of turbulent helicity. Here we first outline the principal patterns
  that have to be explained: the 11-year activity cycle, the 22-year
  magnetic cycle and the longer term modulation of cyclic activity,
  associated with grand maxima and minima. Then we summarise what has
  been learnt from helioseismology about the Sun's internal structure
  and rotation that may be relevant to our subject. The ingredients
  of mean-field dynamo models are differential rotation, meridional
  circulation, turbulent diffusion, flux pumping and the α-effect:
  in various combinations they can reproduce the principal features
  that are observed. To proceed further, it is necessary to rely on
  large-scale computation and we summarise the current state of play.

Title: The Origin and Dynamics of Solar Magnetism
Authors: Thompson, M. J.; Balogh, A.; Culhane, J. L.; Nordlund, Å.;
   Solanki, S. K.; Zahn, J. -P.
Bibcode: 2009odsm.book.....T
Altcode:
  No abstract at ADS

Title: Helioseismology of Sunspots: A Case Study of NOAA Region 9787
Authors: Gizon, L.; Schunker, H.; Baldner, C. S.; Basu, S.; Birch,
   A. C.; Bogart, R. S.; Braun, D. C.; Cameron, R.; Duvall, T. L.;
   Hanasoge, S. M.; Jackiewicz, J.; Roth, M.; Stahn, T.; Thompson, M. J.;
   Zharkov, S.
Bibcode: 2009odsm.book..249G
Altcode:
  Various methods of helioseismology are used to study the subsurface
  properties of the sunspot in NOAA Active Region 9787. This sunspot
  was chosen because it is axisymmetric, shows little evolution during
  20-28 January 2002, and was observed continuously by the MDI/SOHO
  instrument. AR 9787 is visible on helioseismic maps of the farside of
  the Sun from 15 January, i.e. days before it crossed the East limb.

Title: Recent Developments in Local Helioseismology
Authors: Thompson, M. J.; Zharkov, S.
Bibcode: 2008SoPh..251..225T
Altcode: 2008SoPh..tmp...42T
  Local helioseismology is providing new views of subphotospheric flows
  from supergranulation to global-scale meridional circulation and for
  studying structures and dynamics in the quiet Sun and active regions. In
  this short review we focus on recent developments, and in particular
  on a number of current issues, including the sensitivity of different
  measures of travel time and testing the forward modelling used in local
  helioseismology. We discuss observational and theoretical concerns
  regarding the adequacy of current analyses of waves in sunspots and
  active regions, and we report on recent progress in the use of numerical
  simulations to test local helioseismic methods.

Title: Time   Distance Analysis of the Emerging Active Region
    NOAA 10790
Authors: Zharkov, S.; Thompson, M. J.
Bibcode: 2008SoPh..251..369Z
Altcode: 2008arXiv0807.3000Z; 2008SoPh..tmp..140Z
  We investigate the emergence of Active Region NOAA 10790 by means of
  time - distance helioseismology. Shallow regions of increased sound
  speed at the location of increased magnetic activity are observed,
  with regions becoming deeper at the locations of sunspot pores. We also
  see a long-lasting region of decreased sound speed located underneath
  the region of the flux emergence, possibly relating to a temperature
  perturbation due to magnetic quenching of eddy diffusivity, or to
  a dense flux tube. We detect and track an object in the subsurface
  layers of the Sun characterised by increased sound speed which could
  be related to emerging magnetic-flux and thus obtain a provisional
  estimate of the speed of emergence of around 1 km s<SUP>−1</SUP>.

Title: Editors' note
Authors: Jiménez Reyes, S. J.; Reese, D. R.; Thompson, M. J.
Bibcode: 2008AN....329..439J
Altcode:
  No abstract at ADS

Title: Views of the Solar Torsional Oscillation
Authors: Howe, R.; Komm, R. W.; Hill, F.; Schou, J.; Thompson, M. J.
Bibcode: 2008AGUSMSP41A..05H
Altcode:
  The pattern of zonal flows migrating towards the equator over the
  solar cycle, known as the torsional oscillation, is well established
  from both helioseismology and surface Doppler measurements. However,
  the exact appearance of the pattern will vary depending on the form of
  the overall rotation profile that has been subtracted, even when the
  data cover a full eleven-year cycle. Here we compare the appearance
  of the flow pattern when applying several different methods to the
  MDI and GONG data for Solar Cycle 23.

Title: Stellar Astrophysical Fluid Dynamics
Authors: Thompson, Michael J.; Christensen-Dalsgaard, Jørgen
Bibcode: 2008safd.book.....T
Altcode:
  Preface; 1. A selective overview Jørgen Christensen-Dalsgaard and
  Michael J. Thompson; Part I. Stellar Convection and Oscillations:
  2. On the diversity of stellar pulsations Wojciech A. Dziembowski;
  3. Acoustic radiation and mode excitation by turbulent convection
  Günter Houdek; 4. Understanding roAp stars Margarida S. Cunha; 5. Waves
  in the magnetised solar atmosphere Colin S. Rosenthal; Part II. Stellar
  Rotation and Magnetic Fields: 6. Stellar rotation: a historical survey
  Leon Mestel; 7. The oscillations of rapidly rotating stars Michel
  Rieutord; 8. Solar tachocline dynamics: eddy viscosity, anti-friction,
  or something in between? Michael E. McIntyre; 9. Dynamics of the solar
  tachocline Pascale Garaud; 10. Dynamo processes: the interaction of
  turbulence and magnetic fields Michael Proctor; 11. Dynamos in planets
  Chris Jones; Part III. Physics and Structure of Stellar Interiors:
  12. Solar constraints on the equation of state Werner Däppen;
  13. 3He transport and the solar neutrino problem Chris Jordinson;
  14. Mixing in stellar radiation zones Jean-Paul Zahn; 15. Element
  settling and rotation-induced mixing in slowly rotating stars Sylvie
  Vauclair; Part IV. Helio- and Asteroseismology: 16. Solar structure
  and the neutrino problem Hiromoto Shibahashi; 17. Helioseismic data
  analysis Jesper Schou; 18. Seismology of solar rotation Takashi Sekii;
  19. Telechronohelioseismology Alexander Kosovichev; Part V. Large-Scale
  Numerical Experiments: 20. Bridges between helioseismology and models
  of convection zone dynamics Juri Toomre; 21. Numerical simulations of
  the solar convection zone Julian R. Elliott; 22. Modelling solar and
  stellar magnetoconvection Nigel Weiss; 23. Nonlinear magnetoconvection
  in the presence of a strong oblique field Keith Julien, Edgar Knobloch
  and Steven M. Tobias; 24. Simulations of astrophysical fluids Marcus
  Brüggen; Part VI. Dynamics: 25. A magic electromagnetic field Donald
  Lynden-Bell; 26. Continuum equations for stellar dynamics Edward
  A. Spiegel and Jean-Luc Thiffeault; 27. Formation of planetary systems
  Douglas N. C. Lin; 28. The solar-cycle global warming as inferred from
  sky brightness variation Wasaburo Unno and Hiromoto Shibahashi.

Title: Meridional flow profile measurements with SOHO/MDI
Authors: Mitra-Kraev, U.; Thompson, M. J.
Bibcode: 2007AN....328.1009M
Altcode: 2007arXiv0711.4968M
  We present meridional flow measurements of the Sun using a novel
  helioseismic approach for analyzing SOHO/MDI data in order to push
  the current limits in radial depth. Analyzing three consecutive months
  of data during solar minimum, we find that the meridional flow is as
  expected poleward in the upper convection zone, turns equatorward at a
  depth of around 40 Mm (∼0.95 R_⊙), and possibly changes direction
  again in the lower convection zone. This may indicate two meridional
  circulation cells in each hemisphere, one beneath the other.

Title: Varied Mechanisms for Star Formation in Bright-Rimmed Clouds
Authors: Morgan, Larry; Urquhart, J.; Thompson, M.; White, G.;
   Figura, C.
Bibcode: 2007AAS...211.8914M
Altcode: 2007BAAS...39..880M
  Bright-rimmed clouds (BRCs) are potential examples of triggered
  star-formation regions, in which photoionisation driven shocks caused
  by the expansion of HII regions induce protostellar collapse within the
  clouds. A sample of optically bright BRCs at the edge of HII regions
  has been observed at multiple wavelengths in order to investigate the
  possibility that star-formation is present. Such activity may be related
  to photoionisation induced shocks caused by the massive stars powering
  the HII regions. <P />The sample has been observed at radio, infrared
  and submillimetre wavelengths, these observations reveal dense cores
  present within the heads of 44 observed BRCs drawn from a catalogue of
  IRAS sources embedded within HII regions, supportive of the scenario
  proposed by radiatively driven implosion (RDI) models. The physical
  properties of these cores indicate the presence of star formation
  across the majority of our sample. This star-formation appears to
  be predominately in the regime of intermediate to high mass and may
  indicate the formation of clusters. IR observations indicate the
  association of early star forming sources with the sample. <P />A
  fundamental difference appears to exist between different morphological
  types of BRC. Morphological variations in BRCs have previously been
  attributed to an evolutionary scenario of RDI. However, the physical
  properties of cores found within different types of BRC indicate that
  the strength of the ambient ionisation field is highly correlated with
  the attributes of certain cores, and not with others. The suggestion
  is that different morphological types of BRC have followed different
  evolutionary pathways, this is supported by the mass distributions of
  cores associated with the different morphologies.

Title: Asteroseismology and interferometry
Authors: Cunha, M. S.; Aerts, C.; Christensen-Dalsgaard, J.;
   Baglin, A.; Bigot, L.; Brown, T. M.; Catala, C.; Creevey, O. L.;
   Domiciano de Souza, A.; Eggenberger, P.; Garcia, P. J. V.; Grundahl,
   F.; Kervella, P.; Kurtz, D. W.; Mathias, P.; Miglio, A.; Monteiro,
   M. J. P. F. G.; Perrin, G.; Pijpers, F. P.; Pourbaix, D.; Quirrenbach,
   A.; Rousselet-Perraut, K.; Teixeira, T. C.; Thévenin, F.; Thompson,
   M. J.
Bibcode: 2007A&ARv..14..217C
Altcode: 2007arXiv0709.4613C
  Asteroseismology provides us with a unique opportunity to improve
  our understanding of stellar structure and evolution. Recent
  developments, including the first systematic studies of solar-like
  pulsators, have boosted the impact of this field of research within
  astrophysics and have led to a significant increase in the size of
  the research community. In the present paper we start by reviewing
  the basic observational and theoretical properties of classical and
  solar-like pulsators and present results from some of the most recent
  and outstanding studies of these stars. We centre our review on those
  classes of pulsators for which interferometric studies are expected
  to provide a significant input. We discuss current limitations to
  asteroseismic studies, including difficulties in mode identification
  and in the accurate determination of global parameters of pulsating
  stars, and, after a brief review of those aspects of interferometry
  that are most relevant in this context, anticipate how interferometric
  observations may contribute to overcome these limitations. Moreover,
  we present results of recent pilot studies of pulsating stars involving
  both asteroseismic and interferometric constraints and look into the
  future, summarizing ongoing efforts concerning the development of
  future instruments and satellite missions which are expected to have
  an impact in this field of research.

Title: Joint Discussion 17 Highlights of recent progress in the
    seismology of the Sun and Sun-like stars
Authors: Bedding, Timothy R.; Brun, Allan S.; Christensen-Dalsgaard,
   Jørgen; Crouch, Ashley; De Cat, Peter; García, Raphael A.; Gizon,
   Laurent; Hill, Frank; Kjeldsen, Hans; Leibacher, John W.; Maillard,
   Jean-Pierre; Mathis, S.; Rabello-Soares, M. Cristina; Rozelot,
   Jean-Pierre; Rempel, Matthias; Roxburgh, Ian W.; Samadi, Réza; Talon,
   Suzanne; Thompson, Michael J.
Bibcode: 2007HiA....14..491B
Altcode:
  The seismology and physics of localized structures beneath the surface
  of the Sun takes on a special significance with the completion in
  2006 of a solar cycle of observations by the ground-based Global
  Oscillation Network Group (GONG) and by the instruments on board the
  Solar and Heliospheric Observatory (SOHO). Of course, the spatially
  unresolved Birmingham Solar Oscillation Network (BiSON) has been
  observing for even longer. At the same time, the testing of models of
  stellar structure moves into high gear with the extension of deep probes
  from the Sun to other solar-like stars and other multi-mode pulsators,
  with ever-improving observations made from the ground, the success of
  the MOST satellite, and the recently launched CoRoT satellite. Here
  we report the current state of the two closely related and rapidly
  developing fields of helio- and asteroseimology.

Title: Forward modelling of sub-photospheric flows for time-distance
    helioseismology
Authors: Shelyag, S.; Erdélyi, R.; Thompson, M. J.
Bibcode: 2007A&A...469.1101S
Altcode: 2007astro.ph..3067S
  Context: The results of forward modelling of acoustic wave propagation
  in a realistic solar sub-photosphere with two cases of steady
  horizontal flows are presented and analysed by the means of local
  helioseismology. <BR />Aims: This paper is devoted to an analysis
  of the influence of steady flows on the propagation of sound waves
  through the solar interior. <BR />Methods: The simulations are based
  on fully compressible ideal hydrodynamical modelling in a Cartesian
  grid. The initial model is characterised by solar density and pressure
  stratifications taken from the standard Model S and is adjusted in
  order to suppress convective instability. Acoustic waves are excited
  by a non-harmonic source located below the depth corresponding to
  the visible surface of the Sun. Numerical experiments with coherent
  horizontal flows of linear and Gaussian dependences of flow speed on
  depth are carried out. These flow fields may mimic horizontal motions
  of plasma surrounding a sunspot, differential rotation or meridional
  circulation. An inversion of the velocity profiles from the simulated
  travel time differences is carried out. The inversion is based on
  the ray approximation. The results of inversion are then compared
  with the original velocity profiles. <BR />Results: The results
  of forward modelling of acoustic wave propagation in a realistic
  solar sub-photosphere with two cases of steady horizontal flows are
  presented. The influence of steady flow on the propagation of sound
  waves through the solar interior is analysed. A time-distance analysis
  technique is applied to compute the direct observable signatures of
  the background bulk motions on travel times and phase shifts. This
  approach allows direct comparison with observational data. Further,
  we propose a method of obtaining the travel-time differences for the
  waves propagating in sub-photospheric solar regions with horizontal
  flows. The method employs directly the difference between travel-time
  diagrams of waves propagating with and against the background flow. <BR
  />Conclusions: The analysis shows that the flow speed profiles obtained
  from inversion based on the ray approximation differ from the original
  ones. The difference between the original and observed profiles is
  caused by the fact that the wave packets propagate along the ray
  bundle, which has a finite extent, and thus reach deeper regions of
  the sub-photosphere in comparison with ray theory.

Title: Optimized data masks for focussed solar tomography: background
    and artificial diagnostic experiments
Authors: Hughes, S. J.; Pijpers, F. P.; Thompson, M. J.
Bibcode: 2007A&A...468..341H
Altcode:
  Context: The use of solar tomography for detecting subsurface
  features in the Sun is now well established. It customarily proceeds
  from an analysis of data on the solar surface given weightings in
  a predetermined geometric (e.g. centre-annulus) configuration. <BR
  />Aims: We seek to improve these weightings by developing a scheme for
  choosing optimal combinations of data that maximise the contribution
  from signal at a desired horizontal and depth location. <BR />Methods:
  We employ a subtractive optimally localized averaging (SOLA) scheme
  to pick weights for particular data points and analyse the quality of
  the results. <BR />Results: We show in this work that particularly by
  using wave kernels instead of rays for modelling purposes, one can do
  well at localizing a measurement through our techniques while achieving
  desirable error-magnification properties.

Title: Solar Cycle Changes Over 11 Years of Medium-Degree Helioseismic
    Observations
Authors: Howe, Rachel; Komm, R. W.; Hill, F.; Christensen-Dalsgaard,
   J.; Schou, J.; Thompson, M. J.
Bibcode: 2007AAS...210.2218H
Altcode: 2007BAAS...39..127H
  The Global Oscillations Network Group (GONG) has now completed, and
  the Michelson Doppler Imager (MDI) aboard SOHO will soon complete,
  a full eleven years of continuous observations of the medium-degree
  solar oscillations. This enables us to follow changes in the acoustic
  mode parameters and interior dynamics over a full solar cycle. We
  present results from observations of convection-zone dynamics, in
  which the torsional oscillation pattern seen at the surface can be
  followed throughout most of the bulk of the convection zone, and also
  changes in the frequency, lifetime and amplitude of the modes which
  can be shown to be closely related in space and time to the migrating
  pattern of surface activity. <P />This work utilizes data obtained by
  the Global Oscillation Network Group (GONG) program, managed by the
  National Solar Observatory, which is operated by AURA, Inc. under a
  cooperative agreement with the National Science Foundation. SOHO is
  a mission of international cooperation between ESA and NASA.

Title: Time distance study of isolated sunspots
Authors: Zharkov, S.; Nicholas, C. J.; Thompson, M. J.
Bibcode: 2007AN....328..240Z
Altcode: 2008arXiv0802.2524Z
  We present a comparative seismic study of conditions around and beneath
  isolated sunspots. Using the European Grid of Solar Observations'
  Solar Feature Catalogue of sunspots derived from SOHO/MDI continuum and
  magnetogram data, 1996-2005, we identify a set of isolated sunspots by
  checking that within a Carrington Rotation there were no other spots
  detected in the vicinity. We then use level-2 tracked MDI Dopplergrams
  available from SOHO website to investigate wave-speed perturbations
  of such sunspots using time-distance helioseismology.

Title: A procedure for the inversion of f-mode travel times for
    solar flows
Authors: Jackiewicz, J.; Gizon, L.; Birch, A. C.; Thompson, M. J.
Bibcode: 2007AN....328..234J
Altcode: 2007astro.ph..2345J
  We perform a two-dimensional inversion of f-mode travel times
  to determine near-surface solar flows. The inversion is based on
  optimally localized averaging of travel times. We use finite-wavelength
  travel-time sensitivity functions and a realistic model of the data
  errors. We find that it is possible to obtain a spatial resolution
  of 2 Mm. The error in the resulting flow estimate ultimately depends
  on the observation time and the number of travel distances used in
  the inversion.

Title: Outstanding problems in local helioseismology
Authors: Gizon, L.; Thompson, M. J.
Bibcode: 2007AN....328..204G
Altcode: 2010arXiv1002.2347G
  Time-distance helioseismology and related techniques show great promise
  for probing the structure and dynamics of the subphotospheric layers
  of the Sun. Indeed time-distance helioseismology has already been
  applied to make inferences about structures and flows under sunspots
  and active regions, to map long-lived convective flow patterns, and
  so on. Yet certainly there are still many inadequacies in the current
  approaches and, as the data get better and the questions we seek to
  address get more subtle, methods that were previously regarded as
  adequate are no longer acceptable. Here we give a short and partial
  description of outstanding problems in local helioseismology, using
  time-distance helioseismology as a guiding example.

Title: The Effect of Abnormal Granulation on Acoustic Wave Travel
    Times and Mode Frequencies
Authors: Petrovay, K.; Erdélyi, R.; Thompson, M. J.
Bibcode: 2007SoPh..240..197P
Altcode: 2007astro.ph..2076P
  Observations indicate that in plage areas (i.e. in active regions
  outside sunspots) acoustic waves travel faster than in the quiet Sun,
  leading to shortened travel times and higher p-mode frequencies. Coupled
  with the 11-year variation of solar activity, this may also explain the
  solar cycle variation of oscillation frequencies. While it is clear
  that the ultimate cause of any difference between the quiet Sun and
  plage is the presence of magnetic fields of order 100 G in the latter,
  the mechanism by which the magnetic field exerts its influence has
  not yet been conclusively identified. One possible such mechanism is
  suggested by the observation that granular motions in plage areas tend
  to be slightly "abnormal", dampened compared to the quiet Sun.

Title: A Magnetometer For The Solar Orbiter Mission
Authors: Carr, C. M.; Horbury, T. S.; Balogh, A.; Baumjohann, W.;
   Bavassano, B.; Breen, A.; Burgess, D.; Cargill, P. J.; Brooker, N.;
   Erdõs, G.; Fletcher, L.; Forsyth, R. J.; Giacalone, J.; Glassmeier,
   K. -H.; Hoeksema, J. T.; Goldstein, M. L.; Lockwood, M.; Magnes, W.;
   Masimovic, M.; Marsch, G.; Matthaeus, W. H.; Murphy, N.; Nakariakov,
   V. M.; Pacheco, J. R.; Pincon, J. -L.; Riley, P.; Russell, C. T.;
   Schwartz, S. J.; Szabo, A.; Thompson, M.; Vainio, R.; Velli, M.;
   Vennerstrom, S.; Walsh, R.; Wimmer-Schweingruber, R.; Zank, G.
Bibcode: 2007ESASP.641E..41C
Altcode:
  The magnetometer is a key instrument to the Solar Orbiter mission. The
  magnetic field is a fundamental parameter in any plasma: a precise
  and accurate measurement of the field is essential for understanding
  almost all aspects of plasma dynamics such as shocks and stream-stream
  interactions. Many of Solar Orbiter's mission goals are focussed
  around the links between the Sun and space. A combination of in situ
  measurements by the magnetometer, remote measurements of solar magnetic
  fields and global modelling is required to determine this link and
  hence how the Sun affects interplanetary space. The magnetic field
  is typically one of the most precisely measured plasma parameters and
  is therefore the most commonly used measurement for studies of waves,
  turbulence and other small scale phenomena. It is also related to the
  coronal magnetic field which cannot be measured directly. Accurate
  knowledge of the magnetic field is essential for the calculation of
  fundamental plasma parameters such as the plasma beta, Alfvén speed
  and gyroperiod. We describe here the objectives and context of magnetic
  field measurements on Solar Orbiter and an instrument that fulfils those
  objectives as defined by the scientific requirements for the mission.

Title: The Parkes methanol multibeam survey
Authors: Cohen, R. J.; Caswell, J. L.; Brooks, K.; Burton, M. G.;
   Chrysostomou, A.; Cox, J.; Diamond, P. J.; Ellingsen, S.; Fuller,
   G. A.; Gray, M. D.; Green, J. A.; Hoare, M. G.; Masheder, M. R. W.;
   McClure-Griffiths, N.; Pestalozzi, M.; Phillips, C.; Thompson, M.;
   Voronkov, M.; Walsh, A.; Ward-Thompson, D.; Wong-McSweeney, D.; Yates,
   J. A.
Bibcode: 2007IAUS..237..403C
Altcode: 2006IAUS..237E..89B
  A new 7-beam methanol multibeam receiver was successfully commissioned
  at Parkes in January, and has begun surveying the Milky Way for newly
  forming stars, that are pinpointed by strong methanol maser emission
  at 6.7 GHz. The Parkes survey of the Milky Way for methanol masers is
  two orders of magnitude faster than previous systematic surveys using
  30-m class dishes. The first 26 days of observations have yielded
  377 methanol sources, of which 150 are new discoveries. Preliminary
  results will be presented.

Title: Observational results and issues concerning the tachocline
Authors: Christensen-Dalsgaard, Jørgen; Thompson, Michael J.
Bibcode: 2007sota.conf...53C
Altcode:
  No abstract at ADS

Title: Temporal variations in solar rotation at the bottom of the
convection zone: The current status
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R.;
   Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2007AdSpR..40..915H
Altcode:
  We present the most recent results on the short-period variations
  in the solar rotation rate near the base of the convection zone. The
  1.3-year period which was reported in the early years of solar cycle 23
  appears not to persist after 2001, but there are hints of fluctuations
  at a different period during the declining phase of the cycle.

Title: T he Solar Dynamo - What Have We Learned From Helioseismology?
Authors: Thompson, M. J.
Bibcode: 2007ESASP.641E..25T
Altcode: 2006ESASP.641E..25T
  Helioseismology provides a unique tool for probing the solar dynamo by
  observing the evolution of the solar interior over the solar activity
  cycle. In particular, helioseismology has now imaged the subphotospheric
  large-scale flows (solar subsurface weather), differential rotation
  and meridional circulation. It has also probed the stratifica- tion
  and flows under active regions and sunspots. Here I briefly review the
  recent advances from helioseismology in probing aspects of the solar
  interior relevant to an understanding of the solar dynamo problem, and
  assess the current state of theoretical modelling of the solar dynamo.

Title: The Pulsation Properties of the Double-Mode RR Lyrae Variable
    V79 in Messier 3
Authors: Clement, C. M.; Thompson, M.
Bibcode: 2007JAVSO..35..336C
Altcode:
  The double-mode RR Lyrae variable V79 in M3 was observed on seven nights
  in April 2006 with a 14-inch Schmidt-Cassegrain telescope. A total
  of 275 CCD frames were obtained. An analysis of these observations
  indicates that the first overtone period P1 was 0.3590 day, the
  fundamental period P0 was 0.4834 day, and the amplitude ratio A1 /A0
  was 1.00 ± 0.22. These results imply that the fundamental period
  increased and that the strength of the fundamental mode oscillations
  relative to the first-overtone may have increased since 1998 when the
  star was previously observed. The data also indicate that the periods
  may fluctuate from cycle to cycle.

Title: Forward Modeling of Acoustic Wave Propagation in the Quiet
    Solar Subphotosphere
Authors: Shelyag, S.; Erdélyi, R.; Thompson, M. J.
Bibcode: 2006ApJ...651..576S
Altcode:
  The results of numerical simulations of acoustic wave propagation
  and dispersion in the nonmagnetic solar subphotosphere are
  presented. Initial equilibrium density and pressure stratifications are
  taken from a standard solar model but modified to suppress convective
  instabilities in fully compressible two-dimensional ideal hydrodynamical
  modeling. Acoustic waves are generated by sources located below the
  height corresponding to the visible solar surface. The dynamic response
  of the solar interior to two acoustic source types, namely a harmonic
  source and one representing downward-propagating photospheric plumes,
  is studied. A large number of randomly distributed localized cooling
  sources with random amplitudes is also introduced. The methods used to
  analyze the simulation data are similar to ones used in observational
  studies in local helioseismology. Time-distance diagrams of the pressure
  and vertical velocity perturbations at the level corresponding to the
  solar surface show the appearance of wave packets propagating with
  different speeds, which are reflected at different depths beneath the
  subphotosphere. The (ω, k<SUB>h</SUB>) power spectra, derived from the
  vertical velocity data, show the existence of g-, f-, and p-modes p-mode
  ridges are identifiable up to high radial orders of n~11 g-modes appear
  in the simulations, unlike in the real Sun, where they cannot propagate
  in the convectively unstable solar subphotosphere. Cross-correlation
  analysis of vertical velocity perturbations shows a good correspondence
  with the observed time-distance helioseismic data for quiet Sun. Thus,
  the ability of the implemented approach of forward modeling to
  investigate propagation of acoustic, internal, and surface gravity
  waves in a realistic solar interior model is shown.

Title: Helioseismology of sub-photospheric flows
Authors: Shelyag, S.; Erdélyi, R.; Thompson, M. J.
Bibcode: 2006ESASP.624E.123S
Altcode: 2006soho...18E.123S
  No abstract at ADS

Title: The DynaMICS perspective
Authors: Turck-Chièze, S.; Schmutz, W.; Thuillier, G.; Jefferies,
   S.; Pallé; Dewitt, S.; Ballot, J.; Berthomieu, G.; Bonanno, A.;
   Brun, A. S.; Christensen-Dalsgaard, J.; Corbard, T.; Couvidat, S.;
   Darwich, A. M.; Dintrans, B.; Domingo, V.; Finsterle, W.; Fossat,
   E.; Garcia, R. A.; Gelly, B.; Gough, D.; Guzik, J.; Jiménez, A. J.;
   Jiménez-Reyes, S.; Kosovichev, A.; Lambert, P.; Lefebvre, S.; Lopes,
   I.; Martic, M.; Mathis, S.; Mathur, S.; Nghiem, P. A. P.; Piau, L.;
   Provost, J.; Rieutord, M.; Robillot, J. M.; Rogers, T.; Roudier, T.;
   Roxburgh, I.; Rozelot, J. P.; Straka, C.; Talon, S.; Théado, S.;
   Thompson, M.; Vauclair, S.; Zahn, J. P.
Bibcode: 2006ESASP.624E..24T
Altcode: 2006soho...18E..24T
  No abstract at ADS

Title: The effects of rotation on frequency of stellar oscillations
Authors: Burke, K. D.; Thompson, M. J.
Bibcode: 2006ESASP.624E.107B
Altcode: 2006soho...18E.107B
  No abstract at ADS

Title: European helio- and asteroseismology network   HELAS
Authors: Roth, M.; Luhe, O. v. d.; Palle, P.; Thompson, M. J.;
   Christensen-Dalsgaard, J.; Monteiro, M. J. P. F. G.; Gizon, L.;
   Di Mauro, M. P.; Aerts, C.; Daszynska-Daszkiewicz, J.; Corbard, T.
Bibcode: 2006ESASP.624E.130R
Altcode: 2006soho...18E.130R
  The Helio- and Asteroseismology Network (HELAS) is a Coordinated
  Action funded by the FP6-Infrastructure-Programme of the European
  Commission. Currently, HELAS consists of ten members. The objective
  of HELAS is to co-ordinate European activities in helio- and
  asteroseismology. HELAS will transfer knowledge and data analysis
  techniques, and will prepare the European research community for
  important missions in the immediate future.

Title: Effect of sunspot structure from p-modes scattering
Authors: Gordovskyy, M.; Jain, R.; Thompson, M. J.
Bibcode: 2006ESASP.624E..14G
Altcode: 2006soho...18E..14G
  No abstract at ADS

Title: Meridional flow measurements with statistical waveform analysis
Authors: Mitra-Kraev, U.; Thompson, M. J.; Woodard, M. F.
Bibcode: 2006ESASP.624E..57M
Altcode: 2006soho...18E..57M
  No abstract at ADS

Title: Comparative study of isolated sunspots using time-distance
    helioseismology
Authors: Zharkov, S.; Nicholas, C. J.; Thompson, M. J.
Bibcode: 2006ESASP.624E..61Z
Altcode: 2006soho...18E..61Z
  No abstract at ADS

Title: Solar Convection Zone Dynamics: How Sensitive Are Inversions
    to Subtle Dynamo Features?
Authors: Howe, R.; Rempel, M.; Christensen-Dalsgaard, J.; Hill, F.;
   Komm, R.; Larsen, R. M.; Schou, J.; Thompson, M. J.
Bibcode: 2006ApJ...649.1155H
Altcode:
  The nearly 10 year span of medium-degree helioseismic data from the
  Global Oscillation Network Group and the Michelson Doppler Imager has
  allowed us to study the evolving flows in the solar convection zone
  over most of solar cycle 23. Using two independent two-dimensional
  rotation inversion techniques and extensive studies of the resolution
  using artificial data from different assumed flow profiles, including
  those generated from sample mean field dynamo models, we attempt to
  assess the reality of certain features seen in the inferred rotation
  profiles. Our results suggest that the findings from observations of
  a substantial depth dependence of the phase of the zonal flow pattern
  in the low latitudes, and the penetration of the flows deep into the
  convection zone, are likely to be real rather than artifacts of the
  inversion process.

Title: SOHO 18/GONG 2006/HELAS I, Beyond the spherical Sun
Authors: Fletcher, Karen; Thompson, Michael
Bibcode: 2006ESASP.624E....F
Altcode: 2006soho...18E....F
  No abstract at ADS

Title: Time-Distance Measurements of Cross-Correlation Asymmetries
    around NOAA AR 10486
Authors: Jensen, Jesper M.; Pijpers, Frank P.; Thompson, Michael J.
Bibcode: 2006ApJ...648L..75J
Altcode:
  We apply time-distance helioseismology to NOAA AR 10486 in order
  to examine the effect the presence of magnetic fields has on the
  resulting cross-correlations. Large-amplitude asymmetries between waves
  propagating in opposite directions are observed. The asymmetries can
  be attributed to suppression and absorption of seismic waves by the
  magnetic field. Unraveling the effects of magnetic field on the waves
  from the effects of sound-speed perturbations and flows is one of the
  major challenges facing time-distance helioseismology.

Title: Vista Variables in the Via Lactea (VVV)
Authors: Ahumada, A. V.; Minniti, D.; Adamson, A.; Bandyopadhyay, R.;
   Barbá, R.; Barbuy, B.; Barlow, M.; Bedin, L.; Bica, E.; Borissova,
   J.; Bronfman, L.; Carraro, G.; Casassus, S.; Catelan, M.; Clariá,
   J.; Cropper, M.; Dalton, N.; de Grijs, R.; Drew, J.; Eisloeffel, J.;
   Emerson, J.; Fabregat, J.; García, P.; Geisler, D.; Giannini, T.;
   Gieren, W.; Goldman, B.; Gosling, A.; Groot, P.; Hambly, N.; Hoare,
   M.; Irwin, M.; Ivanov, V.; Kerber, L.; Kurtev, R.; Longmore, A.;
   López-Corredoira, M.; Lucas, P.; Lucey, J.; McGowan, K.; Mennickent,
   R.; Messineo, M.; Mirabel, F.; Monaco, L.; Morelli, L.; Naylor, T.;
   Pietrzynski, G.; Pignata, G.; Rejkuba, M.; Ruiz, M. T.; Saviane, I.;
   Schreiber, M.; Schroeder, A.; Stephens, A.; Tappert, C.; Thompson,
   M.; Vanzi, L.; Walton, N.; White, G.; Zijlstra, A.; Zoccali, M.
Bibcode: 2006IAUJD..13E..50A
Altcode:
  We describe a proposal for a public IR variability survey of the entire
  Milky Way Bulge and a large portion of the Southern Galactic Plane
  with VISTA at ESO Paranal Observatory. The survey will take about 180
  nights, covering 5×10^8 point sources within an area of about 600 sq
  deg, including 40 known globular clusters and more than one hundred
  known open clusters. The final products of our VVV survey will be a
  deep IR atlas of the bulge and inner disk, along with a catalogue of
  more than a million variable point sources. These will allow to map
  the 3-D structure of the bulge and inner disk (unlike single epoch
  surveys that only give 2-D maps) using well understood primary distance
  indicators such as RR-Lyrae stars, and to obtain important information
  on the age of the Milky Way stellar populations. The survey will also
  detect hundreds of star formation regions, and allow to examine the
  environmental dependence of star formation. The VISTA observations
  will be combined with data from MACHO, OGLE, EROS, 2MASS, DENIS, VST,
  SPITZER, HST, CHANDRA, INTEGRAL and ALMA for a complete understanding
  of the variable sources in the inner Milky Way. Several important
  implications for the history of the Milky Way, for globular cluster
  evolution, for the population census of the bulge and center, and for
  pulsation theory would follow from this survey.

Title: Scientific Objectives of the Novel Formation Flying Mission
    Aspiics
Authors: Turck-Chièze, S.; Schmutz, W.; Thuillier, G.; Jefferies,
   S.; Pallé; Dewitt, S.; Ballot, J.; Berthomieu, G.; Bonanno, A.;
   Brun, A. S.; Christensen-Dalsgaard, J.; Corbard, T.; Couvidat, S.;
   Darwich, A. M.; Dintrans, B.; Domingo, V.; Finsterle, W.; Fossat,
   E.; Garcia, R. A.; Gelly, B.; Gough, D.; Guzik, J.; Jiménez, A. J.;
   Jiménez-Reyes, S.; Kosovichev, A.; Lambert, P.; Lefebvre, S.; Lopes,
   I.; Martic, M.; Mathis, S.; Mathur, S.; Nghiem, P. A. P.; Piau, L.;
   Provost, J.; Rieutord, M.; Robillot, J. M.; Rogers, T.; Roudier, T.;
   Roxburgh, I.; Rozelot, J. P.; Straka, C.; Talon, S.; Théado, S.;
   Thompson, M.; Vauclair, S.; Zahn, J. P.
Bibcode: 2006ESASP.617E.164L
Altcode: 2006soho...17E.164L
  No abstract at ADS

Title: On the Choice of Phase-Speed Filters For Helioseismic
    Travel-Time Measurements
Authors: Zharkov, S.; Jensen, J. M.; Thompson, M. J.
Bibcode: 2006ESASP.617E..48Z
Altcode: 2006soho...17E..48Z
  No abstract at ADS

Title: The EUV Variability Experiment (EVE) on the Solar Dynamics
Observatory (SDO): Science Plan and Instrument Overview
Authors: Turck-Chièze, S.; Schmutz, W.; Thuillier, G.; Jefferies,
   S.; Pallé; Dewitt, S.; Ballot, J.; Berthomieu, G.; Bonanno, A.;
   Brun, A. S.; Christensen-Dalsgaard, J.; Corbard, T.; Couvidat, S.;
   Darwich, A. M.; Dintrans, B.; Domingo, V.; Finsterle, W.; Fossat,
   E.; Garcia, R. A.; Gelly, B.; Gough, D.; Guzik, J.; Jiménez, A. J.;
   Jiménez-Reyes, S.; Kosovichev, A.; Lambert, P.; Lefebvre, S.; Lopes,
   I.; Martic, M.; Mathis, S.; Mathur, S.; Nghiem, P. A. P.; Piau, L.;
   Provost, J.; Rieutord, M.; Robillot, J. M.; Rogers, T.; Roudier, T.;
   Roxburgh, I.; Rozelot, J. P.; Straka, C.; Talon, S.; Théado, S.;
   Thompson, M.; Vauclair, S.; Zahn, J. P.
Bibcode: 2006ESASP.617E.165W
Altcode: 2006soho...17E.165W
  No abstract at ADS

Title: Sound Wave Travel Times in Plage Areas - The Effect of
    Abnormal Granulation
Authors: Petrovay, K.; Erdélyi, R.; Thompson, M. J.
Bibcode: 2006ESASP.617E..73P
Altcode: 2006soho...17E..73P
  No abstract at ADS

Title: Helas-European Helio- and Asteroseismology Network
Authors: Roth, M.; Lühe, O. v. d.; Pallé, P.; Thompson, M.;
   Christensen-Dalsgaard, J.; Monteiro, M. J. P. F. G; Gizon, L.; Di
   Mauro, M. P.; Aerts, C.; Daszynska-Daszkiewicz, J.; Corbard, T.
Bibcode: 2006ESASP.617E.157R
Altcode: 2006soho...17E.157R
  No abstract at ADS

Title: Sensitivity of Time-Distance Helioseismic Measurements to
    Spatial Variation of Oscillation Amplitudes. I. Observations and a
    Numerical Model
Authors: Rajaguru, S. P.; Birch, A. C.; Duvall, T. L., Jr.; Thompson,
   M. J.; Zhao, J.
Bibcode: 2006ApJ...646..543R
Altcode: 2006astro.ph..4048R
  It is well known that the observed amplitude of solar oscillations is
  lower in sunspots than in quiet regions of the Sun. We show that this
  local reduction in oscillation amplitudes, combined with the phase-speed
  filtering procedure in time-distance helioseismic analyses, could be
  a source of systematic errors in the range of 5%-40% in the measured
  travel-time anomalies of acoustic waves around sunspots. Removing
  these travel-time artifacts is important for correctly inferring the
  subsurface structure of sunspots. We suggest an empirical correction
  procedure and illustrate its usage for a small sunspot. This work uses
  data from SOHO MDI.

Title: The Dynamics Project
Authors: Turck-Chièze, S.; Schmutz, W.; Thuillier, G.; Jefferies,
   S.; Pallé; Dewitt, S.; Ballot, J.; Berthomieu, G.; Bonanno, A.;
   Brun, A. S.; Christensen-Dalsgaard, J.; Corbard, T.; Couvidat, S.;
   Darwich, A. M.; Dintrans, B.; Domingo, V.; Finsterle, W.; Fossat,
   E.; Garcia, R. A.; Gelly, B.; Gough, D.; Guzik, J.; Jiménez, A. J.;
   Jiménez-Reyes, S.; Kosovichev, A.; Lambert, P.; Lefebvre, S.; Lopes,
   I.; Martic, M.; Mathis, S.; Mathur, S.; Nghiem, P. A. P.; Piau, L.;
   Provost, J.; Rieutord, M.; Robillot, J. M.; Rogers, T.; Roudier, T.;
   Roxburgh, I.; Rozelot, J. P.; Straka, C.; Talon, S.; Théado, S.;
   Thompson, M.; Vauclair, S.; Zahn, J. P.
Bibcode: 2006ESASP.617E.162T
Altcode: 2006soho...17E.162T
  No abstract at ADS

Title: Triggered star formation in bright-rimmed clouds: the Eagle
    nebula revisited
Authors: Miao, J.; White, Glenn J.; Nelson, R.; Thompson, M.;
   Morgan, L.
Bibcode: 2006MNRAS.369..143M
Altcode: 2006astro.ph..3230M; 2006MNRAS.tmp..464M
  A three-dimensional smoothed particle hydrodynamics model has been
  extended to study the radiation-driven implosion effect of massive stars
  on the dynamical evolution of surrounding molecular clouds. The new
  elements in the upgraded code are the inclusion of Lyman continuum in
  the incident radiation flux and the treatment of hydrogen ionization
  process; the introduction of ionization heating and recombination
  cooling effects; and the addition of a proper description of the
  magnetic and turbulent pressures to the internal pressure of the
  molecular cloud. This extended code not only provides a realistic model
  to trace the dynamical evolution of a molecular cloud, but also can be
  used to model the kinematics of the ionization and shock fronts and the
  photoevaporating gas surrounding the molecular cloud, which the previous
  code is unable to handle. <P />The application of this newly developed
  model to the structure of the middle Eagle nebula finger suggests that
  the shock induced by the ionizing radiation at the front side of the
  head precedes an ionization front moving towards the centre of the core,
  and that the core at the fingertip is at a transition stage evolving
  toward a state of induced star formation. The dynamical evolution
  of the velocity field of the simulated cloud structure is discussed
  to illustrate the role of the self-gravity and the different cloud
  morphologies which appear at different stages in the evolutionary
  process of the cloud. The motion of the ionization front and the
  evaporating gas are also investigated. The modelled gas evaporation
  rate is consistent with that of other current models and the density,
  temperature and chemical profiles are in agreement with the observed
  values. <P />The relative lifetimes of different simulated cloud
  morphologies suggest a possible answer to the question of why more
  bright-rimmed clouds are observed to possess a flat-core than an
  elongated-core morphology.

Title: Large-Scale Zonal Flows Near the Solar Surface
Authors: Howe, R.; Komm, R.; Hill, F.; Ulrich, R.; Haber, D. A.;
   Hindman, B. W.; Schou, J.; Thompson, M. J.
Bibcode: 2006SoPh..235....1H
Altcode:
  Migrating bands of weak, zonal flow, associated with the activity
  bands in the solar cycle, have been observed at the solar surface for
  some time. More recently, these flows have been probed deep within the
  convection zone using global helioseismology and examined in more detail
  close to the surface with the techniques of local helioseismology. We
  compare the near-surface results from global and local helioseismology
  using data from the Michelson Doppler Imager and the Global Oscillation
  Network Group with surface Doppler velocity measurements from the Mount
  Wilson 150-foot tower and find that the results are in reasonable
  agreement, with some explicable differences in detail. All of the
  data sets show zones of faster rotation approaching the equator from
  mid-latitudes during the solar cycle, with a variation at any given
  location that can be approximately, but not completely, described by a
  single sinusoid and an amplitude that does not drop off steeply below
  the surface.

Title: Magnetohelioseismology
Authors: Thompson, Michael J.
Bibcode: 2006RSPTA.364..297T
Altcode:
  No abstract at ADS

Title: An introduction to astrophysical fluid dynamics
Authors: Thompson, Michael J.
Bibcode: 2006iafd.book.....T
Altcode:
  No abstract at ADS

Title: Jets in the Solar Tachocline as Diagnostics of Global MHD
    Processes
Authors: Christensen-Dalsgaard, J.; Corbard, T.; Dikpati, M.; Gilman,
   P. A.; Thompson, M. J.
Bibcode: 2005ASPC..346..115C
Altcode:
  Multiple theories predict the existence of prograde fluid jets in the
  solar tachocline. We find helioseismic evidence of a prograde jet near
  60° latitude in N and S hemispheres that persists through almost all
  of the current solar cycle. This evidence favors a hydrodynamic origin
  for the jet, from global instability of the differential rotation of
  the tachocline. We see no evidence for jets that migrate toward the
  equator with the advancing solar cycle, which tends to rule out jets
  associated with toroidal field bands in the tachocline.

Title: Solar Convection-Zone Dynamics, 1995-2004
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R.;
   Schou, J.; Thompson, M. J.
Bibcode: 2005ApJ...634.1405H
Altcode:
  The nine-year span of medium-degree helioseismic data from the Global
  Oscillation Network Group (GONG) and the Michelson Doppler Imager (MDI)
  allows us to study the evolving zonal flows in the solar convection
  zone over the rising phase, maximum, and early declining phase
  of solar cycle 23. Using two independent two-dimensional rotation
  inversion techniques, we investigate the depth profile of the flow
  pattern known as the torsional oscillation. The observations suggest
  that the flows penetrate deep within the convection zone-perhaps to
  its base-even at low latitudes, and that the phase of the pattern is
  approximately constant along lines of constant rotation rather than
  lines of constant latitude.

Title: Acoustic Wave Propagation in the Solar Subphotosphere
Authors: Shelyag, S.; Erdelyi, R.; Thompson, M. J.
Bibcode: 2005AGUFMSH53A1237S
Altcode:
  Local time-distance helioseismology aims to get an information about the
  internal structure of subphotospheric region of the Sun, like flows and
  sound speed perturbations, by investigation of observed travel times
  of the oscillatory responses of subphotosphere to a perturbation. We
  present the results of simulations of acoustic wave propagation and
  dispersion in the non-magnetic solar subphotosphere. We use methods
  similar to the observational ones to produce results aiming to reproduce
  observational data from local helioseismology. The VAC code (G. Toth)
  is used to carry out the simulations. The code can solve the full system
  of ideal hydrodynamic equations in two or three dimensions. All the
  results presented are carried out in 2D. The simulations use realistic
  solar density and pressure stratifications and are based on fully
  compressible ideal hydrodynamical model. Acoustic waves are produced
  by perturbations located near the layer corresponding to the visible
  surface of the Sun. The simulation domain is 150 Mm wide and 52.6 Mm
  deep, and has a resolution of 600x4000 grid points; the upper boundary
  of the domain is near the temperature minimum. The density profile for
  the initial plane-parallel model is taken from Christensen-Dalsgaard's
  standard Model S. We suppress convective motions of the fluid in the
  domain by slight change of adiabatic index γ_1. This approach has
  an advantage among other approaches because the waves we study, while
  they propagate through the quiescent medium, can be clearly observed
  far from the source undisturbed by convective fluid motions. First
  we study the propagation of acoustic waves produced by a harmonic
  pressure perturbation, then, in order to follow the criteria of realism
  we introduce more involved perturbation source, described as a source
  in the energy equation of the HD system of equations. The source used
  corresponds to a localized cooling event causing mass inflow and
  sound waves extinction (M. Rast, 1999). In order to reproduce the
  helioseismogram of the quiet Sun we introduce a number of randomly
  distributed sources with random amplitudes and present a comparison
  of the simulated data with the observations.

Title: How Sensitive are Rotation Inversions to Subtle Features of
    the Dynamo?
Authors: Howe, R.; Rempel, M.; Christensen-Dalsgaard, J.; Schou, J.;
   Thompson, M. J.; Komm, R.; Hill, F.
Bibcode: 2005ASPC..346...99H
Altcode:
  Global rotation inversions can probe the pattern of zonal flows
  well into the convection zone. In this paper, we test the ability
  of the inversions to constrain the predictions of dynamo models. A
  flux-transport dynamo model, including a mean-field theory of
  differential rotation and allowing for feedback of the Lorentz force
  on differential rotation and meridional flow, was used to produce a
  22-year cycle of simulated rotation profiles. These were then subjected
  to simulated inversions with realistic mode sets and errors, in order
  to test how well the subtle subsurface features of the input profile
  could be recovered. The preliminary results are quite encouraging.

Title: Preface (Advances in astronomy. From the big bang to the
    solar system)
Authors: Thompson, Michael
Bibcode: 2005aabb.bookD..11T
Altcode:
  No abstract at ADS

Title: Seismic analysis of the second ionization region of helium
    in the Sun - I. Sensitivity study and methodology
Authors: Monteiro, Mário J. P. F. G.; Thompson, Michael J.
Bibcode: 2005MNRAS.361.1187M
Altcode: 2005astro.ph..6286M; 2005MNRAS.tmp..632M
  The region of the second ionization of helium in the Sun is a narrow
  layer near the surface. Ionization induces a local change in the
  adiabatic exponent Γ<SUB>1</SUB>, which produces a characteristic
  signature in the frequencies of p modes. By adapting the method
  developed by Monteiro, Christensen-Dalsgaard &amp; Thompson, we propose
  a methodology for determining the properties of this region by studying
  such a signature in the frequencies of oscillation. <P />Using solar
  data we illustrate how the signal from the helium ionization zone can
  be isolated. Using solar models which each use different physics - the
  theory of convection, equation of state and low-temperature opacities -
  we establish how the characteristics of the signal depend on the various
  physical processes contributing to the structure in the ionization
  layer. We further discuss how the method can be used to measure the
  solar helium abundance in the envelope and to constrain the physics
  affecting this region of the Sun. <P />The potential usefulness of the
  method we propose is shown. It may complement other inversion methods
  developed to study the solar structure and to determine the envelope
  helium abundance.

Title: Comparison of GONG and MDI: Sound-Speed Anomalies beneath
    Two Active Regions
Authors: Hughes, S. J.; Rajaguru, S. P.; Thompson, M. J.
Bibcode: 2005ApJ...627.1040H
Altcode:
  Travel times of acoustic waves are calculated from Dopplergrams of solar
  oscillations obtained using the Global Oscillation Network Group (GONG)
  ground-based network and the Michelson Doppler Imager (MDI) instrument
  on board the SOHO satellite. These travel times are inverted using
  a standard ray approximation to ascertain the sound-speed anomalies
  below two active regions. Some simple methods for ignoring the possibly
  corrupted measurements from within a sunspot are considered, as are
  diagnostics for optimizing the inversion. Results are then presented
  for two different spot regions, and the results of the instruments
  are compared: both regions behave in similar ways, and the agreement
  between the two instruments is good. First-skip and second-skip data
  are found to produce similar results for deeper layers of the model,
  but the significance of the shallower results from second-skip data
  is questionable. We conclude that GONG data are appropriate for
  time-distance analysis.

Title: Global, Local and Surface Measurements of Large-Scale Zonal
    Flows Near the Solar Surface
Authors: Howe, R.; Komm, R. W.; Haber, D. A.; Hindman, B. W.; Ulrich,
   R. K.; Schou, J.; Thompson, M. J.; Hill, F.
Bibcode: 2005AGUSMSP32A..03H
Altcode:
  Migrating bands of weak zonal flow, associated with the activity
  bands in the solar cycle, have been observed at the solar surface
  for some time. More recently, these flows have been probed deep
  within the convection zone using global helioseismology, and
  examined in more detail close to the surface with the techniques of
  local helioseismology. We compare the results from global and local
  helioseismology using data from the Michelson Doppler Imager and the
  GONG network and also Doppler measurements from Mount Wilson, and find
  that the results are in reasonable agreement, with some explicable
  differences in detail. This was work was supported by the National
  Science Foundation and NASA.

Title: Helioseismic Ring Analyses of Artificial Data Computed for
    Two-dimensional Shearing Flows
Authors: Hindman, Bradley W.; Gough, Douglas; Thompson, Michael J.;
   Toomre, Juri
Bibcode: 2005ApJ...621..512H
Altcode:
  The local helioseismological technique of ring analysis has been
  crucial in the discovery of complex large-scale flows in the Sun's
  near-surface shear layer. However, current implementations of
  ring-analysis procedures assume that the flow field is horizontally
  homogeneous over the analysis region. This assumption is certainly
  incorrect, and in the present paper we assess the significance of this
  approximation by analyzing artificial data sets computed from models of
  horizontal shear flows. We consider the simple case of purely horizontal
  and unidirectional flow that varies solely in the horizontal direction
  orthogonal to the flow in a piecewise-constant manner. An ensemble
  of plane waves is incident on the flow, and the scattered wave field
  produced by the prescribed two-dimensional flow is computed to generate
  an artificial helioseismic power spectrum. The artificial spectrum
  is processed in a manner similar to standard ring analysis, and the
  flow field that is thereby inferred is compared with the known imposed
  flow. We find that the inferred flow velocity is essentially an average
  of the true flow velocity over the region of the analysis, weighted by
  the square of the spatial apodization function used in processing the
  oscillation signal. Furthermore, the shape of a p-mode line profile
  is determined by the distribution of speeds across the analysis region.

Title: The use of frequency-separation ratios for asteroseismology
Authors: Otí Floranes, H.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 2005MNRAS.356..671O
Altcode: 2005MNRAS.356..671F
  The systematic patterns of separations between frequencies of modes of
  different degree and order are a characteristic of p-mode oscillations
  of stars. The frequency separations depend on the internal structure
  of the star and so measuring them in the observed oscillation spectra
  of variable stars gives valuable diagnostics of the interior of a
  star. Roxburgh &amp; Vorontsov proposed using the ratio of the so-called
  small frequency separation to the large frequency separation as a
  diagnostic of the stellar interior, and demonstrated that this ratio
  was less sensitive than the individual frequency separations themselves
  to uncertain details of the near-surface structure. Here we derive
  kernels relating the frequency separation ratio to structure, and show
  why the ratio is relatively insensitive to the near-surface structure
  in terms of the very small amplitude of the kernels in the near-surface
  layers. We also investigate the behaviour of the separation ratio for
  stars of different masses and ages, and demonstrate the usefulness of
  the ratio in the so-called asteroseismic Hertzsprung-Russell diagram.

Title: Local Modulation of Solar Oscillations by Magnetic Fields
Authors: Nicholas, C. J.; Thompson, M. J.; Rajaguru, S. P.
Bibcode: 2004SoPh..225..213N
Altcode:
  The amplitudes of solar oscillations measured in Doppler velocity are
  modulated by the presence of a strong photospheric magnetic field. Here
  we show that the amount of modulation cannot be predicted solely
  on the local photospheric magnetic field strength. Qualitatively,
  magnetic fields of similar strength have similar effects on the
  oscillations. Quantitatively, however, we find a `neighborhood effect',
  so that the presence of a nearby sunspot affects oscillations in
  the area in its vicinity that has normal quiet-Sun magnetic field
  strength. Thus, different types of magnetic regions alter the
  oscillatory power to a varying degree, and the p-mode power within
  regions of similar magnetic field strength is more reduced if there is
  a sunspot present. The neighborhood effect falls off with distance from
  the sunspot. We also show that our measurements of the power modulation,
  in which we look at the effects on oscillations pixel by pixel, can
  be made consistent with results of amplitude modulation of modes as
  obtained from ring-diagram analysis of active regions, but only if
  the neighborhood effect on quiet-Sun regions is taken into account.

Title: Comparison of GONG and MDI Sound-Speed Anomalies Beneath Two
    Active Regions
Authors: Hughes, S. J.; Rajaguru, S. P.; Thompson, M. J.
Bibcode: 2004ESASP.559..493H
Altcode: 2004soho...14..493H
  No abstract at ADS

Title: Detection of Jets and Associated Toroidal Fields in the
    Solar Tachocline
Authors: Christensen-Dalsgaard, J.; Corbard, T.; Dikpati, M.; Gilman,
   P. A.; Thompson, M. J.
Bibcode: 2004ESASP.559..376C
Altcode: 2004soho...14..376C
  No abstract at ADS

Title: How Sensitive are Rotation Inversions to Subtle Features of
    the Dynamo?
Authors: Howe, R.; Rempel, M.; Christensen-Dalsgaard, J.; Hill, F.;
   Komm, R. W.; Schou, J.; Thompson, M. J.
Bibcode: 2004ESASP.559..468H
Altcode: 2004soho...14..468H
  No abstract at ADS

Title: The Effect of Strong Magnetic Fields on Acoustic Power in
    Their Surroundings at the Surface of the Sun
Authors: Nicholas, C. J.; Thompson, M. J.; Rajaguru, S. P.
Bibcode: 2004ESASP.559..590N
Altcode: 2004soho...14..590N
  No abstract at ADS

Title: Optimal Masks for Deep Focussing
Authors: Hughes, S. J.; Pijpers, F. P.; Thompson, M. J.
Bibcode: 2004ESASP.559..488H
Altcode: 2004soho...14..488H
  No abstract at ADS

Title: Subphotospheric Flows Near Active Region NOAA 10486
Authors: Haber, D. A.; Hindman, B. W.; Toomre, J.; Bogart, R. S.;
   Thompson, M. J.
Bibcode: 2004ESASP.559..148H
Altcode: 2004soho...14..148H
  No abstract at ADS

Title: The Phase of the Torsional Oscillation Pattern
Authors: Howe, R.; Komm, R. W.; Hill, F.; Christensen-Dalsgaard, J.;
   Schou, J.; Thompson, M. J.
Bibcode: 2004ESASP.559..476H
Altcode: 2004soho...14..476H
  No abstract at ADS

Title: Asteroseismology: Asteroseismology of Sun-like stars
Authors: Elsworth, Yvonne P.; Thompson, Michael J.
Bibcode: 2004A&G....45e..14E
Altcode:
  Seismology has become a powerful tool for analysis of the interior
  of the Sun; it has great potential for the study of oscillations in
  solar-like stars. Asteroseimology could provide direct information
  about detailed properties of stellar interiors, bringing the potential
  for testing theories of stellar evolution and structure. Current
  stellar models are simple with few direct observational constraints;
  consequences such as age estimates are uncertain to a factor of two. A
  recent attempt at asteroseismology on Procyon, a likely candidate
  star, found no detectable oscillations. In this paper we discuss the
  asteroseismology of solar-like stars in the context of studies of the
  Sun and then indicate possible reasons for the Procyon results.

Title: Application of Local-Area Helioseismic Methods as Predictors
    of Space Weather
Authors: Jensen, J. M.; Lundstedt, H.; Thompson, M. J.; Pijpers,
   F. P.; Rajaguru, S. P.
Bibcode: 2004ESASP.559..497J
Altcode: 2004soho...14..497J
  No abstract at ADS

Title: Convection-Zone Dynamics from GONG and MDI, 1995-2004
Authors: Howe, R.; Komm, R. W.; Hill, F.; Christensen-Dalsgaard, J.;
   Haber, D. A.; Schou, J.; Thompson, M. J.
Bibcode: 2004ESASP.559..472H
Altcode: 2004soho...14..472H
  No abstract at ADS

Title: Solar interior: Helioseismology and the Sun's interior
Authors: Thompson, Michael J.
Bibcode: 2004A&G....45d..21T
Altcode:
  Helioseismology is the study of the solar interior using observations
  of waves on the Sun's surface. It has done much to improve our
  understanding of the interior of the Sun, testing the physical
  inputs used to model stellar interiors and providing a detailed map
  of the Sun's structure and internal rotation. This in turn has greatly
  influenced theories of the solar magnetic dynamo. These interior studies
  thus make a valuable bridge between solar physics and studies of the
  structure and evolution of other stars. Recent developments include new
  local techniques for unprecedented studies of subsurface structures
  and flows in emerging active regions, under sunspots, and even of
  active regions on the far side of the Sun. These developments hold
  the possibility of a real understanding of how the interior links to
  solar magnetic activity in the corona and heliosphere. Finally, studies
  such as those of the deep solar interior are on the verge of becoming
  possible for other stars exhibiting similar multimode oscillations.

Title: Subphotospheric Flows Around Active Region NOAA 10486
Authors: Haber, D. A.; Hindman, B. W.; Toomre, J.; Bogart, R. S.;
   Thompson, M. J.; LoHCo Team
Bibcode: 2004AAS...204.0211H
Altcode: 2004BAAS...36Q.669H
  We have used MDI Dynamics Program Doppler data taken between October
  18th and November 15th 2003 to study the interaction of solar subsurface
  flows with NOAA 10486, one of the most dynamic active regions of the
  past solar cycle. Using the local helioseismic techniques of ring and
  time-distance analyses, we assess the horizontal flows that surrounded
  and permeated this region and how they varied with depth in the upper
  14 Mm of the convection zone. We examine and identify structures in the
  flow field that may have been associated with the energetic flares that
  occurred during the period of observation. This research is in part
  supported by NASA through grants NAG5-11920, NAG5-10917, and NAG5-12491.

Title: Comparison OF Noise Properties Of GONG And MDI Time-Distance
    Helioseismic Data
Authors: Rajaguru, S. P.; Hughes, S. J.; Thompson, M. J.
Bibcode: 2004SoPh..220..381R
Altcode:
  The recently upgraded system of the ground-based Global Oscillation
  Network Group (GONG) network of helioseismic observatories has started
  to provide higher-resolution solar oscillation measurements suitable
  for local helioseismic studies. Selecting simultaneously observed
  regions on the Sun by both GONG and the space-borne Michelson Doppler
  Imager (MDI) instrument on board the Solar and Heliospheric Observatory
  (SOHO), we perform a comparative analysis of time-distance measurements
  focussing on the noise properties.

Title: Organized Subsurface Flows near Active Regions
Authors: Haber, D. A.; Hindman, B. W.; Toomre, J.; Thompson, M. J.
Bibcode: 2004SoPh..220..371H
Altcode:
  Local helioseismic techniques, such as ring analysis and time-distance
  helioseismology, have already shown that large-scale flows near the
  surface converge towards major active regions. Ring analysis has further
  demonstrated that at greater depths some active regions exhibit strong
  outflows. A critique leveled at the ring-analysis results is that the
  Regularized Least Squares (RLS) inversion kernels on which they are
  based have negative sidelobes near the surface. Such sidelobes could
  result in a surface inflow being misidentified as a diverging outflow
  at depth. In this paper we show that the Optimally Located Averages
  (OLA) inversion technique, which produces kernels without significant
  sidelobes, generates flows markedly similar to the RLS results. Active
  regions are universally zones of convergence near the surface, while
  large complexes evince strong outflows deeper down.

Title: ENEAS: the European Network of Excellence in AsteroSeismology
Authors: Aerts, C.; Baglin, A.; Christensen-Dalsgaard, J.; Goupil,
   M. J.; Houdek, G.; Kjeldsen, H.; Kollath, Z.; Kurtz, D.; Lebreton,
   Y.; Maceroni, C.; Noels, A.; Schwarzenberg-Czerny, A.; Škoda, P.;
   Solano, E.; Thompson, M. J.
Bibcode: 2004ESASP.538..247A
Altcode: 2004sshp.conf..247A
  Asteroseismology is one of the major important science topics in
  astrophysics in the coming decade. Several recent breakthroughs have
  indeed been made in Europe in this field. The observational data will
  improve significantly in the near future, as upgraded ground-based
  instruments are being built and two European asteroseismic space
  missions are planned for launch between 2005 and 2008. They will
  provide us for the first time with ultra-high-accuracy, high-temporal
  resoluton data from space for stars other than the Sun. A successful
  asteroseismic study involves many different steps, from state-of-the-art
  raw data treatment to theoretical physical modelling of the oscillation
  frequencies. Our network is set up to meet the needs of combining and
  exchanging the different expertises of the participating institutes, of
  training PhD students and of both training and exchanging post-doctoral
  researchers. This will guarantee the most fruitful and efficient
  exploitation of the very substantial investments that are being made in
  Europe in future observations of stellar oscillations, strengthening
  Europe's leading position in this research field. Also, it will be a
  test-bed for the development of efficient procedures for collaboration
  across the internet, involving a vast range of procedures and skills,
  as well as extensive common use of a broad variety of data. Furthermore,
  procedures will be incorporated for the joint training of students,
  which is an essential part of our project.

Title: Application of local-area helioseismic methods as predictors
    of spaceweather
Authors: Jensen, J. M.; Lundstedt, H.; Thompson, M. J.; Pijpers,
   F. P.; Rajaguru, S. P.
Bibcode: 2004cosp...35.2195J
Altcode: 2004cosp.meet.2195J
  Many of the phenomena observed on the Sun are of magnetic origin. The
  solar wind, Coronal Mass Ejections and flares are all phenomena
  closely linked to Sun's magnetic field. The technology based society
  of today can be strongly influences by these phenomena. The high
  energetic particles emitted in connection with CMEs and flares are
  able to cause enough damage to satellites to render them useless. It
  is therefore of great interest to understand the physical processes
  behind these phenomena. During the last three decades helioseismology
  has investigated the solar interior by measurements of the global
  eigenmode frequencies. The global nature of these data makes it
  impossible to resolve phenomena which are highly localized in the
  Sun. Within the last decade local-area helioseismic methods have emerged
  as powerful tools for investigating localized phenomena in the solar
  convection zone such as flows and magnetic activity. With these methods
  it has become possible to study structures around and below active
  regions. Observations have been made of flows and temperature variations
  surrounding and extending below sunspots thereby enabling the study of
  dynamical processes below the solar surface in actice regions. These
  studies can help to understand the processes behind phenomena such
  as flares and CMEs which can influence the Earth. With local-area
  helioseismic methods a wealth of new information has or will become
  available, which hopefully can be used to increase the reliability
  of space weather predictions. With the data available from the SOHO
  satellite and the GONG network it is possible to monitor large-scale
  flows in the Sun in connection with magnetic active regions using
  local-area helioseismic methods. We propose to use these observed flows
  as indicators for future space weather. If observations of the magnetic
  configuration in active regions are supplemented with information of
  the flow fields surrounding the active region it might be possible to
  improve on flare prediction. To this end we propose to use physics-based
  neural network to investigate if the flow fields can be used to predict
  flares and space weather. The goal is to incorporate these data into
  the space weather forecast models developed at the Swedish Institute
  of Space Physics in Lund. A space weather forecast service prototype
  was developed within the ESA Space Weather Programme Study and an ESA
  Pilot Project is in progress. The Lund division of the institute also
  runs the RWC-Sweden of ISES. Here we present preliminary results of
  this new approach of using helioseismological data.

Title: The Significance of Density and Attenuation in the Local
    Helioseismology
Authors: Tong, C. H.; Thompson, M. J.; Warner, M. R.; Pain, C. C.
Bibcode: 2003ApJ...596L.263T
Altcode:
  We present results from numerical simulations in order to demonstrate
  the significance of density and attenuation in helioseismic
  data modeling and in the interpretation of reconstructed solar
  models. Attenuation beneath active regions causes significant dispersion
  as well as temporal shifts of the helioseismic signals. These effects
  can be considerably more significant than those caused by sound-speed
  anomalies. On the basis of the differential changes in the waveform
  of the signals as a function of density, we propose the modeling of
  density for the estimation of the relative contribution from buoyancy
  and magnetic fields toward the origin of the fluid flows in the solar
  interior.

Title: Helioseismic Signals and Wave Field Helioseismology
Authors: Tong, C. H.; Thompson, M. J.; Warner, M. R.; Pain, C. C.
Bibcode: 2003ApJ...593.1242T
Altcode:
  We investigate the effect of sound-speed perturbations on the
  characteristics of helioseismic signals in order to demonstrate
  the feasibility and desirability of wave field helioseismology. The
  oscillatory nature of the signals with varying frequency content allows
  us to characterize the waveform of the signals by the amplitudes of the
  peaks and troughs as well as by the time lags between successive peaks
  and troughs. Sinusoidal sound-speed perturbations with an amplitude
  of 1% of the local sound speed produce more than +/-10% changes in the
  amplitudes of the peaks and troughs. The same sound-speed perturbations
  produce changes in the time lags between successive peaks and troughs
  of the signals that are comparable with the variations of first-break
  travel times of the oscillatory wave packet. The vertical and horizontal
  sound-speed perturbations result in distinct patterns of changes in
  the shape of the helioseismic signals. These changes in the amplitudes
  and travel-time lags are differential for the successive peaks and
  troughs: the magnitude is higher for the later peaks and troughs. We
  also observe that these variations in the amplitude and travel-time
  lags are more sensitive to shorter wavelength sound-speed perturbations
  at relatively small source-receiver offsets. Therefore, our results
  indicate that the waveform of the signals is variable and sensitive to
  sound-speed perturbations. These observations can be explained by the
  more dispersive nature of the low-frequency components in the seismic
  signals at shallow depths. The relatively high sensitivity of these
  perturbations in the waveform of the signals to sound speed, density,
  and vertical density gradient at shallow depths due to dispersion is
  an important modeling consideration.

Title: A Comparison of Solar p-Mode Parameters from MDI and GONG:
    Mode Frequencies and Structure Inversions
Authors: Basu, S.; Christensen-Dalsgaard, J.; Howe, R.; Schou, J.;
   Thompson, M. J.; Hill, F.; Komm, R.
Bibcode: 2003ApJ...591..432B
Altcode:
  Helioseismic analysis of solar global oscillations allows investigation
  of the internal structure of the Sun. One important test of the
  reliability of the inferences from helioseismology is that the
  results from independent sets of contemporaneous data are consistent
  with one another. Here we compare mode frequencies from the Global
  Oscillation Network Group and Michelson Doppler Imager on board SOHO
  and resulting inversion results on the Sun's internal structure. The
  average relative differences between the data sets are typically less
  than 1×10<SUP>-5</SUP>, substantially smaller than the formal errors in
  the differences; however, in some cases the frequency differences show
  a systematic behavior that might nonetheless influence the inversion
  results. We find that the differences in frequencies are not a result
  of instrumental effects but are almost entirely related to the data
  pipeline software. Inversion of the frequencies shows that their
  differences do not result in any significant effects on the resulting
  inferences on solar structure. We have also experimented with fitting
  asymmetric profiles to the oscillation power spectra and find that,
  compared with the symmetric fits, this causes no significant change
  in the inversion results.

Title: First results from Time-Distance inversions of GONG+ data.
Authors: Rajaguru, S. P.; Hughes, S. J.; Thompson, M. J.
Bibcode: 2003SPD....34.0801R
Altcode: 2003BAAS...35..821R
  We present first results from time-distance helioseismic analysis
  of a few active regions using the new merged sequences of data from
  GONG+ instruments. In particular we focus on issues related to the
  resolution achievable from GONG+ data and also estimate their noise
  properties.Results from inversions for sound speed changes beneath
  active regions will be presented with initial comparisons between
  first and second bounce time-distance data for acoustic rays passing
  under a spot. We acknowledge support from the UK Particle Physics and
  Astronomy Research Council.

Title: Stellar Astrophysical Fluid Dynamics
Authors: Thompson, Michael J.; Christensen-Dalsgaard, Jørgen
Bibcode: 2003safd.book.....T
Altcode:
  Preface; 1. A selective overview Jørgen Christensen-Dalsgaard and
  Michael J. Thompson; Part I. Stellar Convection and Oscillations:
  2. On the diversity of stellar pulsations Wojciech A. Dziembowski;
  3. Acoustic radiation and mode excitation by turbulent convection
  Günter Houdek; 4. Understanding roAp stars Margarida S. Cunha; 5. Waves
  in the magnetised solar atmosphere Colin S. Rosenthal; Part II. Stellar
  Rotation and Magnetic Fields: 6. Stellar rotation: a historical survey
  Leon Mestel; 7. The oscillations of rapidly rotating stars Michel
  Rieutord; 8. Solar tachocline dynamics: eddy viscosity, anti-friction,
  or something in between? Michael E. McIntyre; 9. Dynamics of the solar
  tachocline Pascale Garaud; 10. Dynamo processes: the interaction of
  turbulence and magnetic fields Michael Proctor; 11. Dynamos in planets
  Chris Jones; Part III. Physics and Structure of Stellar Interiors:
  12. Solar constraints on the equation of state Werner Däppen;
  13. 3He transport and the solar neutrino problem Chris Jordinson;
  14. Mixing in stellar radiation zones Jean-Paul Zahn; 15. Element
  settling and rotation-induced mixing in slowly rotating stars Sylvie
  Vauclair; Part IV. Helio- and Asteroseismology: 16. Solar structure
  and the neutrino problem Hiromoto Shibahashi; 17. Helioseismic data
  analysis Jesper Schou; 18. Seismology of solar rotation Takashi Sekii;
  19. Telechronohelioseismology Alexander Kosovichev; Part V. Large-Scale
  Numerical Experiments: 20. Bridges between helioseismology and models
  of convection zone dynamics Juri Toomre; 21. Numerical simulations of
  the solar convection zone Julian R. Elliott; 22. Modelling solar and
  stellar magnetoconvection Nigel Weiss; 23. Nonlinear magnetoconvection
  in the presence of a strong oblique field Keith Julien, Edgar Knobloch
  and Steven M. Tobias; 24. Simulations of astrophysical fluids Marcus
  Brüggen; Part VI. Dynamics: 25. A magic electromagnetic field Donald
  Lynden-Bell; 26. Continuum equations for stellar dynamics Edward
  A. Spiegel and Jean-Luc Thiffeault; 27. Formation of planetary systems
  Douglas N. C. Lin; 28. The solar-cycle global warming as inferred from
  sky brightness variation Wasaburo Unno and Hiromoto Shibahashi.

Title: Asteroseismology Across the HR Diagram
Authors: Thompson, M. J.; Cunha, M. S.; Monteiro, M. J. P. F. G.
Bibcode: 2003aahd.conf.....T
Altcode:
  Ground-based observations have detected solar-like oscillations
  on Sun-like stars, and diagnostics similar to those used in
  helioseismology are now being used to test and constrain the physics
  and evolutionary state of these stars. Multi-mode oscillations are
  being observed in an abundance of other stars, including slowly
  pulsating B stars (SPB stars), delta-Scuti stars, Ap stars and the
  pulsating white dwarfs. New classes of pulsators continue to be
  discovered across the Herzsprung-Russell diagram. Yet the chances
  still to be faced to make asteroseismology across the HR diagram
  a reality are formidable. Observation, data analysis and theory
  all pose hard problems to be overcome. This book, reflecting the
  goal of the meeting, aims to facilitate a cross-fertilisation of
  ideas and approaches between fields covering different pulsators
  and with different areas of expertise. The book successfully covers
  most known types of pulsators, reflecting a highly productive and
  far reaching interchange of ideas which we believe is conveyed
  by the papers and posters published, making it a reference for
  researchers and postgraduate students working on stellar structure and
  evolution. <P />Link: <A href="http://www.wkap.nl/prod/b/1-4020-1173-3">
  http://www.wkap.nl/prod/b/1-4020-1173-3</A>

Title: Time-distance analysis of GONG+ data
Authors: Rajaguru, S. P.; Hughes, S. J.; Thompson, M. J.
Bibcode: 2003ESASP.517...75R
Altcode: 2003soho...12...75R
  We show our first time-distance analyses of data from GONG+. We
  present details of our method of analysing the data and travel-time
  anomalies measured over an active region when compared to that over a
  quiet region. The dataset used for studying the active region is from
  a merged sequence of GONG+ Doppler images.

Title: Time-distance helioseismology of subsurface flows
Authors: Hughes, Stephen J.; Thompson, Michael J.
Bibcode: 2003ESASP.517..307H
Altcode: 2003soho...12..307H
  We revisit the work of Giles (1999) in an attempt to extend the
  work on large scale flows using the technique of time-distance
  helioseismology. The basic process and techniques are discussed and some
  initial results are shown. The behaviour of the meridional and zonal
  flows is found to be similar to that found by Giles and separately by
  ring diagram methods (Haber et al. 2002).

Title: Transient oscillations near the solar tachocline
Authors: Toomre, Juri; Christensen-Dalsgaard, Jorgen; Hill, Frank;
   Howe, Rachel; Komm, Rudolf W.; Schou, Jesper; Thompson, Michael J.
Bibcode: 2003ESASP.517..409T
Altcode: 2003soho...12..409T
  We report on further developments in the 1.3-yr quasi-periodic
  oscillations reported by Howe et al. (2000). These are small (6 to 8
  nHz peak-to-peak) oscillations in the inferred rotation rate near the
  bottom of the convection zone and in the outer part of the radiative
  interior. The oscillations are strongest and most coherent at about a
  fractional radius of 0.72 in the equatorial region. Further monitoring
  of the oscillations near the equator shows that they continued for a
  period after the end of the data analyzed by Howe et al., but appear to
  have now diminished in amplitude. This is reminiscent of the transient
  behavior of similar (1.3 to 1.4 yr) periodicities in solar-wind and
  geomagnetic datasets previously reported. We speculate that the near
  tachocline oscillation is associated with the rising phase of the
  solar cycle. We discuss tests performed to eliminate various possible
  explanations of the oscillations due to systematic errors in the data
  and in their analyses.

Title: On variation of the latitudinal structure  of the solar
    convection zone
Authors: Antia, H. M.; Chitre, S. M.; Thompson, M. J.
Bibcode: 2003A&A...399..329A
Altcode: 2002astro.ph.12095A
  The latitudinal sound-speed structure of the Sun's convection zone gives
  insight into the physical processes occurring there, specifically the
  cellular convection and possibly the presence of magnetic fields. Using
  helioseismic data from the GONG network and MDI instrument on SOHO,
  we map the latitudinal acoustic structure of the convection zone from
  1995 to 2002. The temporally averaged structure confirms previous
  findings of an excess in sound speed at the 10<SUP>-4</SUP> level at
  60 degrees latitude. There also appear to be some variation with time,
  with the peak in sound-speed asphericity at 60 degrees growing towards
  the maximum of solar activity according to the MDI data. However,
  we present some evidence that such variation may be associated with
  instrumental variation between the epochs before and after SOHO was
  temporarily lost in 1998. Nonetheless, some genuine temporal variation
  may be present, and we discuss the possible physical causes of that.

Title: Helioseismology present and future
Authors: Thompson, Michael J.
Bibcode: 2003ESASP.517..209T
Altcode: 2003soho...12..209T
  The subject of helioseismology is in a exciting phase of expansion. In
  terms of the methods being developed and applied, the new and
  challenging results coming out from the high-quality data that
  present observational campaigns, networks and missions are providing,
  the arrival of GONG+, the prospects for new missions including Solar
  Dynamics Observatory, and the recent ground-based results and exciting
  prospects for asteroseismology of other solar-like stars. I pick up
  on some themes of the conference, and expand on the above developments
  and activities.

Title: Acoustic Wave Propagation in the Sun: Implications for Wave
    Field and Time-Distance Helioseismology
Authors: Tong, C. H.; Thompson, M. J.; Warner, M. R.; Rajaguru, S. P.;
   Pain, C. C.
Bibcode: 2003ApJ...582L.121T
Altcode:
  We present results of the numerical simulation of acoustic wave
  propagation in the Sun's subphotospheric layers. A finite-difference
  code is used to calculate the pressure perturbation in the frequency
  domain. We show that the oscillatory seismic signals are closely
  associated with the solar density and sound speed structures. Owing
  to the acoustic cutoff frequency, the reduction in the group velocity
  relative to the background sound speed varies significantly with
  frequency, especially at low frequencies. This variation causes
  acoustic wave dispersion, which results in the nonuniform frequency
  content in the oscillatory signals in the wave packets. An asymptotic
  arrival generated by the constructive interference of the high-order
  bounces is observed in the synthetic seismic traces. The synthetic
  seismic traces presented in this study can provide the basis for wave
  field tomography, in which phase and amplitude information (including
  the nonresonant frequencies) is exploited, to enhance the spatial
  resolution of the reconstructed solar models.

Title: Rotation of the solar interior
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 2003dysu.book...55C
Altcode:
  Helioseismology allows us to infer the rotation in the greater part
  of the solar interior with high precision and resolution. The results
  show interesting conflicts with earlier theoretical expectations,
  indicating that the Sun is host to complex dynamical phenomena, so
  far hardly understood. This has important consequences for our ideas
  about the evolution of stellar rotation, as well as for models for
  the generation of the solar magnetic field. An overview of our current
  knowledge about solar rotation is given, much of it obtained from the
  SOHO spacecraft, and the broader implications are discussed.

Title: Preface (Stellar astrophysical fluid dynamics)
Authors: Thompson, Michael J.; Christensen-Dalsgaard, Jørgen
Bibcode: 2003safd.bookD...9T
Altcode:
  No abstract at ADS

Title: On Asteroseismic Constraints for Modelling the δ Scuti Stars
    V480 Tau and θ<SUP>2</SUP> Tau A
Authors: Di Mauro, M. P.; Pijpers, F.; Christensen-Dalsgaard, J.;
   Paternò, L.; Teixeira, T.; Thompson, M. J.
Bibcode: 2003ASPC..305..161D
Altcode: 2003mfob.conf..161D
  We investigate the structure and evolution of δ Scuti stars and
  discuss how basic properties as well as global oscillation frequencies
  are modified by moderate rotation. We present theoretical analyses of
  V480 Tau, observed during the MUSICOS 1996 campaign (Hao et al. 2001),
  and of θ<SUP>2</SUP> Tau A, monitored by the WIRE satellite (Poretti
  et al. 2002). We compare the observed spectra of frequencies with the
  theoretical oscillation frequencies calculated by including rotational
  effects.

Title: Seismological analysis of the Helium ionization zones in low-
    and moderate-mass stars
Authors: Miglio, A.; Christensen-Dalsgaard, J.; di Mauro, M. P.;
   Monteiro, M. J. P. F. G.; Thompson, M. J.
Bibcode: 2003aahd.conf..537M
Altcode:
  The region of the second ionization of helium in solar-like stars is a
  narrow subsurface layer whose thermodynamic properties are responsible
  for the presence of a characteristic signature in the oscillation
  frequencies of the p modes. Here, with the aim of detecting the acoustic
  depth of the second helium ionization zone, we consider two methods
  of analysing the signal generated in the oscillation frequencies by
  the sharp decrease in the first adiabatic exponent Γ<SUB>1</SUB>,
  which occurs where ionization takes place. The properties of the
  ionization zone, once determined by seismological means, may be used
  to put constraints on the structure of the stars, in particular on
  the envelope helium abundance.

Title: Seismic Study of Temporal Variations of Solar Magnetic Field
Authors: Antia, H. M.; Chitre, S. M.; Thompson, M. J.
Bibcode: 2003IAUJD..12E..30A
Altcode:
  The temporal variations of acoustic frequencies of solar oscillations
  with the solar activity cycle are studied with a view to understanding
  the changes in the Sun's internal magnetic field. The data used are
  even a-coefficients from the GONG and MDI observations of the Sun's
  p-mode oscillations. These coefficients describe the modification of the
  frequencies by agents such as magnetic fields or latitudinal thermal
  perturbations that break the spherical symmetry of the Sun but that -
  unlike rotational advection and Coriolis forces - do not distinguish
  eastward- and westward-propagating acoustic waves. It is hoped that
  such a study will shed light on the mechanism of the solar dynamo.

Title: A selective overview
Authors: Christensen-Dalsgaard, Jørgen; Thompson, Michael J.
Bibcode: 2003safd.book....1C
Altcode:
  Contents: 1. Introduction. 2. On taking mixing-length
  theory seriously. 3. The solar spoon. 4. Deep roots of solar
  cycles. 5. Helioseismology: oscillations as a diagnostic of
  the solar interior. 6. Inverting helioseismic data. 7. On the
  detection of subphotospheric convective velocities and temperature
  fluctuations. 8. Prospects for asteroseismic inference.

Title: The Internal Rotation of the Sun
Authors: Thompson, Michael J.; Christensen-Dalsgaard, Jørgen; Miesch,
   Mark S.; Toomre, Juri
Bibcode: 2003ARA&A..41..599T
Altcode:
  Helioseismology has transformed our knowledge of the Sun's
  rotation. Earlier studies revealed the Sun's surface rotation,
  but now a detailed observational picture has been built up of the
  internal rotation of our nearest star. Unlike the predictions of
  stellar-evolution models, the radiative interior is found to rotate
  roughly uniformly. The rotation within the convection zone is also
  very different from prior expectations, which had been that the
  rotation rate would depend primarily on the distance from the rotation
  axis. Layers of rotational shear have been discovered at the base of
  the convection zone and in the subphotospheric layers. Studies of the
  time variation of rotation have uncovered zonal-flow bands, extending
  through a substantial fraction of the convection zone, which migrate
  over the course of the solar cycle, and there are hints of other
  temporal variations and of a jet-like structure. At the same time,
  building on earlier work with mean-field models, researchers have made
  great progress in supercomputer simulations of the intricate interplay
  between turbulent convection and rotation in the Sun's interior. Such
  studies are beginning to transform our understanding of how rotation
  organizes itself in a stellar interior.

Title: A Sub-mm Imaging Survey of Ultracompact HII Regions
Authors: Thompson, M.; Hatchell, J.; MacDonald, G.; Millar, T.
Bibcode: 2002ASPC..267..429T
Altcode: 2001astro.ph.12444T; 2002hsw..work..429T
  Ultracompact (UC) H II regions are currently the best known tracer of
  massive YSOs and represent the earliest confirmed stage of massive star
  formation. In excess of 150 UC HII regions have been detected, mainly
  by radio surveys. Whilst the environments of UC HII regions are known
  very well on the small scale (a few arcseconds) they are not well known
  on scales over 40 arcsec. This is because most UC HII's have, to date,
  been observed using either interferometers (to gain information on small
  scales at the expense of large scales) or by single-position large-beam
  (typically 40 arcsec or worse) spectroscopy. To redress this issue we
  recently undertook an imaging survey of over 100 UC HII regions using
  SCUBA on the JCMT, which enables us to rapidly map with high-resolution
  the dust emission from the clumps in which the UC HII's are embedded.

Title: Induced Star Formation Near HII Regions: the Fate of Three
    Clouds in IC 1848
Authors: Thompson, M.; White, G.; Miao, J.; Fridlund, M.; Huldtgren, M.
Bibcode: 2002ASPC..267..431T
Altcode: 2002hsw..work..431T
  From a combination of NVSS archive radio continuum data and JCMT
  <SUP>12</SUP>CO and <SUP>13</SUP>CO maps we have evaluated the pressure
  balance between the ionised exterior and molecular interior of three
  bright-rimmed clouds. We predict that photo-ionisation shocks are
  currently being driven into two of the clouds whilst the third is
  likely to be in a pre-shock state.

Title: Flux Transport Solar Dynamos with Near-Surface Radial Shear
Authors: Dikpati, Mausumi; Corbard, Thierry; Thompson, Michael J.;
   Gilman, Peter A.
Bibcode: 2002ApJ...575L..41D
Altcode:
  Corbard &amp; Thompson analyzed quantitatively the strong radial
  differential rotation that exists in a thin layer near the solar
  surface. We investigate the role of this radial shear in driving a flux
  transport dynamo operating with such a rotation profile. We show that
  despite being strong, near-surface radial shear effectively contributes
  only ~1 kG (~30% of the total) to the toroidal fields produced there
  unless an abnormally high, surface α-effect is included. While 3 kG
  spot formation from ~1-2 kG toroidal fields by convective collapse
  cannot be ruled out, the evolutionary pattern of these model fields
  indicates that the polarities of spots formed from the near-surface
  toroidal field would violate the observed polarity relationship with
  polar fields. This supports previous results that large-scale solar
  dynamos generate intense toroidal fields in the tachocline, from which
  buoyant magnetic loops rise to the photosphere to produce spots. Polar
  fields generated in flux transport models are commonly much higher
  than observed. We show here that by adding enhanced diffusion in the
  supergranulation layer (originally proposed by Leighton), near-surface
  toroidal fields undergo large diffusive decay preventing spot formation
  from them, as well as reducing polar fields closer to the observed
  values. However, the weaker polar fields lead to the regeneration of
  a toroidal field of less than ~10 kG at the convection zone base,
  too weak to produce spots that emerge in low latitudes, unless an
  additional poloidal field is produced at the tachocline. This is
  achieved by a tachocline α-effect, previously shown to be necessary
  for coupling the north and south hemispheres to ensure toroidal and
  poloidal fields that are antisymmetric about the equator.

Title: Solar internal rotation as seen from SOHO MIDI data
Authors: Vorontsov, S. V.; Christensen-Dalsgaard, J.; Schou, J.;
   Strakhov, V. N.; Thompson, M. J.
Bibcode: 2002ESASP.508..111V
Altcode: 2002soho...11..111V
  We report results of inverting the rotational splittings of solar
  p-mode frequencies measured from the MDI data, using an adaptive
  regularization technique as described by Strakhov &amp; Vorontsov
  (2001). We analyse the spatial and temporal structure of the variations
  in the internal rotation, which constitute the 11-yr solar torsional
  oscillations. We employ all the data collected over half a solar cycle
  to analyse further the time-independent component of the differential
  rotation, particularly focusing on the solar tachocline region. We
  address systematic errors in the rotational splitting measurements,
  as indicated by the inversion residuals, which appear to restrict the
  accuracy of the current helioseismic measurements.

Title: Effect of subsurface radial differential rotation on
    flux-transport solar dynamo
Authors: Corbard, T.; Dikpati, M.; Gilman, P. A.; Thompson, M. J.
Bibcode: 2002ESASP.508...75C
Altcode: 2002soho...11...75C
  A near-surface radial gradient of rotation was recently inferred and
  quantified from MDI f-modes observations by Corbard &amp; Thompson
  (2001). We show, from our preliminary simulation of the large-scale
  solar magnetic field, by using a flux-transport type dynamo, that
  despite being strong, this gradient plays only a small role compared
  to the tachocline in shearing the poloidal fields to produce toroidal
  fields. This happens primarily because the turbulent diffusivity near
  the surface wins in the competition of generation versus decay of
  the magnetic fields unless an abnormally high α-effect is considered
  there. This supports the results of previous flux-transport as well
  as interface and overshoot layer dynamo models that the major toroidal
  fields of the Sun are generated in the tachocline.

Title: Helioseismic Measurement of Solar Torsional Oscillations
Authors: Vorontsov, S. V.; Christensen-Dalsgaard, J.; Schou, J.;
   Strakhov, V. N.; Thompson, M. J.
Bibcode: 2002Sci...296..101V
Altcode:
  Bands of slower and faster rotation, the so-called torsional
  oscillations, are observed at the Sun's surface to migrate in latitude
  over the 11-year solar cycle. Here, we report on the temporal variations
  of the Sun's internal rotation from solar p-mode frequencies obtained
  over nearly 6 years by the Michelson Doppler Imager (MDI) instrument
  on board the Solar and Heliospheric Observatory (SOHO) satellite. The
  entire solar convective envelope appears to be involved in the torsional
  oscillations, with phase propagating poleward and equatorward from
  midlatitudes at all depths throughout the convective envelope.

Title: A Comparison of Solar p-Mode Parameters from the Michelson
Doppler Imager and the Global Oscillation Network Group: Splitting
    Coefficients and Rotation Inversions
Authors: Schou, J.; Howe, R.; Basu, S.; Christensen-Dalsgaard, J.;
   Corbard, T.; Hill, F.; Komm, R.; Larsen, R. M.; Rabello-Soares, M. C.;
   Thompson, M. J.
Bibcode: 2002ApJ...567.1234S
Altcode:
  Using contemporaneous helioseismic data from the Global Oscillation
  Network Group (GONG) and Michelson Doppler Imager (MDI) onboard SOHO,
  we compare frequency-splitting data and resulting inversions about the
  Sun's internal rotation. Helioseismology has been very successful in
  making detailed and subtle inferences about the solar interior. But
  there are some significant differences between inversion results
  obtained from the MDI and GONG projects. It is important for making
  robust inferences about the solar interior that these differences are
  located and their causes eliminated. By applying the different analysis
  pipelines developed by the projects not only to their own data but
  also to the data from the other project, we conclude that the most
  significant differences arise not from the observations themselves
  but from the different frequency estimation analyses used by the
  projects. We find that the GONG pipeline results in substantially fewer
  fitted modes in certain regions. The most serious systematic differences
  in the results, with regard to rotation, appear to be an anomaly in
  the MDI odd-order splitting coefficients around a frequency of 3.5 mHz
  and an underestimation of the low-degree rotational splittings in the
  GONG algorithm.

Title: The subsurface radial gradient of solar angular velocity from
    MDI f-mode observations
Authors: Corbard, T.; Thompson, M. J.
Bibcode: 2002SoPh..205..211C
Altcode: 2001astro.ph.10361C
  We report quantitative analysis of the radial gradient of solar
  angular velocity at depths down to about 15 Mm below the solar surface
  for latitudes up to 75° using the Michelson Doppler Imager (MDI)
  observations of surface gravity waves (fmodes) from the Solar and
  Heliospheric Observatory (SOHO). A negative outward gradient of around
  −400 nHz/R<SUB>⊙</SUB>, equivalent to a logarithmic gradient of
  the rotation frequency with respect to radius which is very close
  to −1, is found to be remarkably constant between the equator and
  30° latitude. Above 30° it decreases in absolute magnitude to a
  very small value at around 50°. At higher latitudes the gradient may
  reverse its sign: if so, this reversal takes place in a thin layer
  extending only 5 Mm beneath the visible surface, as evidenced by the
  most superficial modes (with degrees l&gt;250). The signature of the
  torsional oscillations is seen in this layer, but no other significant
  temporal variations of the gradient and value of the rotation rate
  there are found.

Title: SOLA inversions for the core structure of solar-type stars
Authors: Basu, S.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 2002ESASP.485..249B
Altcode: 2002sshp.conf..249B; 2001astro.ph.10446B
  The Subtractive Optimally Localized Averages (SOLA) method, developed
  and extensively used in helioseismology, is applied to artificial data
  to obtain measures of the sound speed inside a solar-type star. In
  contrast to inversion methods which fit models to some aspect of
  the data, methods such as SOLA provide an honest assessment of
  what can truly be resolved using seismic data, without introducing
  additional assumptions such as that the space of admissible stellar
  models is small. The resulting measures obtained from SOLA inversion
  can subsequently be used to eliminate putative stellar models. Here
  we present results of experiments to test the reliability of SOLA
  inferences using solar models and models of solar-type stars.

Title: On inverting asteroseismic data
Authors: Thompson, M. J.; Christensen-Dalsgaard, J.
Bibcode: 2002ESASP.485...95T
Altcode: 2002sshp.conf...95T; 2001astro.ph.10447T
  Some issues of inverting asteroseismic frequency data are discussed,
  including the use of model calibration and linearized inversion. An
  illustrative inversion of artificial data for solar-type stars,
  using least-squares fitting of a small set of basis functions, is
  presented. A few details of kernel construction are also given.

Title: Asteroseismic inference for solar-type stars
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 2002ESASP.485..291M
Altcode: 2001astro.ph.10445M; 2002sshp.conf..291M
  The oscillation spectra of solar-type stars may in the not-too-distant
  future be used to constrain certain properties of the stars. The C-D
  diagram of large versus small frequency separations is one of the
  powerful tools available to infer the properties - including perhaps
  masses and ages - of stars which display a detectable spectrum of
  oscillation. Also, the border of a convective region in a solar-type
  star gives rise to a characteristic periodic signal in the star's
  low-degree p-mode frequencies. Such a signature contains information
  about the location and nature of the transition between convective and
  non-convective regions in the star. In this work we address some of
  the uncertainties associated with the direct use of the C-D diagram to
  evaluate the mass and age of the star due to the unknown contributions
  that make the stars different from the evolutionary models used to
  construct our reference grid. We also explore the possibility of
  combining an amplitude versus period diagram with the C-D diagram to
  evaluate the properties of convective borders within solar-type stars.

Title: Rotation of the solar interior
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 2001astro.ph.10607C
Altcode:
  Helioseismology has allowed us to infer the rotation in the greater part
  of the solar interior with high precision and resolution. The results
  show interesting conflicts with earlier theoretical expectations,
  indicating that the the Sun is host to complex dynamical phenomena,
  so far hardly understood. This has important consequences for our
  ideas about the evolution of stellar rotation, as well as for models
  for the generation of the solar magnetic field. Here we provide an
  overview of our current knowledge about solar rotation, much of it
  obtained from observations from the SOHO spacecraft, and discuss the
  broader implications.

Title: Variations of the solar interior with the cycle: observational
    aspects.
Authors: Corbard, Thierry; Jimenez-Reyes, S. J.; Thompson, M. J.;
   Tomczyk, S.
Bibcode: 2001sf2a.conf..109C
Altcode:
  Helioseismic observations of long duration now open the possibility of
  studying the variation of the interior of the Sun during its cycle of
  activity. In particular, the possible dynamic or structure variations of
  the interface between the convective zone and the radiative interior,
  or tachocline, is of great interest to constrain solar dynamo models
  and to understand the phenomena at the origin of the cycle of activity
  observed at the surface. We have analysed the observations obtained
  during the 6 last years by the LOWL instrument located at Mauna Loa,
  Hawaii as well as the observations in integrated disc covering more
  than one solar cycle (1984-2000) by MARK-I instrument at the Peak del
  Teide, Tenerife. The results concerning the signature of the solar
  activity on the pressure modes of low and medium degrees and seeks for
  possible variations of the dynamic of the tachocline will be presented
  and replaced in the theoretical context.

Title: Comparing Global Solar Rotation Results from MDI and GONG
Authors: Howe, R.; Komm, R. W.; Hill, F.; Christensen-Dalsgaard, J.;
   Schou, J.; Thompson, M. J.; Corbard, T.
Bibcode: 2001AGUSM..SP31A14H
Altcode:
  The GONG (Global Oscillations Network Group) project and the Solar
  Oscillations Investigation (SOI) using the Michelson Doppler Imager
  (MDI) instrument aboard the SOHO spacecraft have jointly accumulated
  more than five years of data on medium-degree solar p-modes, including
  nearly four years of contemporaneous observations. The inferences of
  interior solar rotation from the two projects are broadly consistent
  and show similar temporal variations, but there are also significant
  systematic differences. We report here on the results of an ongoing
  attempt to cross-compare the results and analysis techniques of the
  two projects. Three 108-day periods, at low, medium and high solar
  activity epochs, have been analysed, with both MDI and GONG analysis
  being applied to each data set, and the results are compared.

Title: Variations in Rotation Rate Within the Solar Convection Zone
    From GONG and MDI 1995-2000
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R. W.;
   Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2001AGUSM..SP31A15H
Altcode:
  Helioseismic measurements with the Michelson Doppler Imager (MDI)
  instrument aboard SOHO, and complementary measurements from the Global
  Oscillation Network Group (GONG) project, are revealing changes deep
  within the Sun as the solar cycle progresses. We will present the
  latest results based on recent data from both experiments, including
  flows in the upper part of the convection zone and variations in the
  rotation rate near its base.

Title: Seismology of solar-type stars
Authors: Basu, S.; Christensen-Dalsgaard, J.; Monteiro, M. J. P. F. G.;
   Thompson, M. J.
Bibcode: 2001ESASP.464..407B
Altcode: 2001soho...10..407B
  Seismology of solar-type stars other than the Sun becomes a realistic
  possibly with the upcoming MOST, COROT and MONS missions, and the
  ESA mission Eddington. We report on the results of experiments with
  artificial data from models of solar-type stars to assess further what
  we might learn about the internal structure of such stars.

Title: Inversion for the solar internal rotation with an adaptive
    regularization technique
Authors: Vorontsov, S. V.; Christensen-Dalsgaard, J.; Schou, J.;
   Strakhov, V. N.; Thompson, M. J.
Bibcode: 2001ESASP.464..559V
Altcode: 2001soho...10..559V
  We report the first preliminary results of applying the adaptive
  regularization technique (Strakhov and Vorontsov 2000) to the inversion
  for the solar internal rotation. The 360d SOHO MDI data set with 18-th
  degree fit to the rotational splittings is used in the 1.5-D and 2-D
  inversions, and we used the 72d data sets (Schou 1999) to trace the
  possible variations with solar activity.

Title: Comparing mode frequencies from MDI and GONG
Authors: Howe, R.; Hill, F.; Basu, S.; Christensen-Dalsgaard, J.;
   Komm, R. W.; Munk Larsen, R.; Roth, M.; Schou, J.; Thompson, M. J.;
   Toomre, J.
Bibcode: 2001ESASP.464..137H
Altcode: 2001soho...10..137H
  We present results of analyses of MDI and GONG time series covering
  the same time intervals, and using both the MDI and GONG peakbagging
  algorithms. We discuss some of the likely causes of differences between
  the inferred frequencies and frequency splittings. In addition, we
  consider the effect of these differences on the results of inversions
  for the solar internal rotation and sound speed.

Title: Solar cycle changes in convection zone dynamics from MDI and
    GONG 1995 - 2000
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R. W.;
   Munk Larsen, R.; Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2001ESASP.464...19H
Altcode: 2001soho...10...19H
  The combined GONG and MDI medium-degree helioseismic data sets now cover
  just over 5 years and allow us to probe the changing dynamics of the
  convection zone in unprecedented detail. Here we present the latest
  results from both projects, showing the evolution of the migrating
  zonal flows close to the surface and also changes close to and below
  the base of the convection zone.

Title: Temporal variations of the Sun's internal structure and
dynamics: a theoretical perspective
Authors: Thompson, Michael J.
Bibcode: 2001ESASP.464...39T
Altcode: 2001soho...10...39T
  As is well known from surface observations of magnetic fields, flow
  fields and radiation fluxes, the Sun is a highly dynamical object
  and varies on many timescales, one of the most prominent being the
  22-year period of the solar activity cycle. Recently there has been
  much direct evidence from helioseismology (e.g. the many contributions
  to this Session) for temporal variations also in the solar interior,
  on timescales of months and years. In this review talk I consider
  the theoretical expectations of how the solar interior (structure,
  magnetic field, velocity field) might change over the solar cycle and
  on other timescales, how these changes can be expected to influence
  the measurable properties of the oscillations, and possible theoretical
  interpretations of some of the recent helioseismic results on temporal
  variations of the solar interior.

Title: Interior Solar-Cycle Changes Detected by Helioseismology
Authors: Howe, R.; Hill, F.; Komm, R. W.; Christensen-Dalsgaard, J.;
   Munk Larsen, R.; Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2001IAUS..203...40H
Altcode:
  Helioseismic measurements with the MDI instrument aboard SOHO,
  and complementary measurements from the GONG network, are revealing
  changes deep within the Sun as the solar cycle progresses. We will
  present results based on recent data from both experiments, including
  variations in the rotation rate deep inside the convection zone.

Title: On the signature of the solar activity at the base of the
    convective envelope
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Schou,
   J.; Thompson, M. J.
Bibcode: 2001ESASP.464..535M
Altcode: 2001soho...10..535M
  A we approach the solar maximum for the current cycle it is timely to
  establish what helioseismology can tell us about the internal changes
  the Sun undergoes as the cycle progresses. In this work we use SOI-MDI
  data in order to identify changes occurring to the stratification of
  the Sun at the base of the convective envelope. Both changes with
  time (averaged over colatitude) and changes over time at different
  colatitudes are addressed. These are discussed in terms of the changes
  in the properties of the convection at the base of the envelope in
  the region where the tachocline is present. Those variations could
  be attributed to the interaction between convection, rotation and
  magnetic fields, which must be intrinsically time-dependent phenomena,
  possibly correlated with the observed changes occurring over the cycle
  in the envelope up to the surface.

Title: The Sun's acoustic asphericity and magnetic fields in the
    solar convection zone
Authors: Antia, H. M.; Chitre, S. M.; Thompson, M. J.
Bibcode: 2000A&A...360..335A
Altcode: 2000astro.ph..5587A
  The observed splittings of solar oscillation frequencies can be employed
  to separate the effects of internal solar rotation and to estimate
  the contribution from a large-scale magnetic field or any latitude-
  dependent thermal perturbation inside the Sun. The surface distortion
  estimated from the rotation rate in the solar interior is found to be
  in good agreement with the observed oblateness at solar surface. After
  subtracting out the estimated contribution from rotation, there is
  some residual signal in the even splitting coefficients, which may be
  explained by a magnetic field of approximately 20 kG strength located
  at a depth of 30000 km below the surface or an equivalent aspherical
  thermal perturbation. An upper limit of 300 kG is derived for a toroidal
  field near the base of the convection zone.

Title: Seismic study of stellar convective regions: the base of the
    convective envelope in low-mass stars
Authors: Monteiro, Mário J. P. F. G.; Christensen-Dalsgaard, Jørgen;
   Thompson, Michael J.
Bibcode: 2000MNRAS.316..165M
Altcode:
  The possibility of observing solar-type oscillations on other stars
  is of great relevance to investigating the uncertain aspects of the
  internal structure of stars. One of these aspects is the convective
  overshoot that takes place at the borders of the envelopes of
  stars of mass similar to, or lower than, the Sun. It affects the
  temperature stratification, mixing, rotation and magnetic-field
  generation. Asteroseismology can provide an observational test for the
  studies of the structure of such overshoot regions. The seismic study of
  the transition in the Sun, located at the base of the convection zone,
  has been successful in determining the characteristics of this layer
  in the Sun. In this work we consider the extension of the analysis to
  other solar-type stars (of mass between 0.85 and 1.2M<SUB>solar</SUB>)
  in order to establish a method for determining the characteristics
  of their convective envelopes. In particular, we hope to be able to
  establish seismologically that a star does indeed possess a convective
  envelope, to measure the size of the convective region and also to
  constrain the properties of an overshoot layer at the bottom of the
  envelope. The limitations in terms of observational uncertainties and
  stellar characteristics, and the detectability of an overshoot layer,
  are discussed.

Title: Helioseismic Search for Magnetic Field in the Solar Interior
Authors: Antia, H. M.; Chitre, S. M.; Thompson, M. J.
Bibcode: 2000JApA...21..343A
Altcode:
  No abstract at ADS

Title: Solar-Cycle Changes in Convection-Zone Dynamics from SOI and
    GONG Data
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R. W.;
   Larsen, R. M.; Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2000SPD....31.0113H
Altcode: 2000BAAS...32..803H
  The combined GONG and MDI medium-degree helioseismic data sets now cover
  more than 4.5 years and allow us to probe the changing dynamics of the
  convection zone in unprecedented detail. Here we present the latest
  results from both projects, showing the evolution of the migrating zonal
  flows close to the surface and also changes close to and below the base
  of the convection zone. This work utilizes data obtained by the Global
  Oscillation Network Group (GONG) project, managed by the National Solar
  Observatory, a Division of the National Optical Astronomy Observatories,
  which is operated by AURA, Inc. under a cooperative agreement with the
  National Science Foundation. SOHO is a joint project of ESA and NASA.

Title: Seismology of solar-type stars
Authors: Thompson, M. J.
Bibcode: 2000mons.proc...15T
Altcode:
  I review the asteroseismology of solar-type stars. The emphasis is on
  the theory of what may be learned and how. I draw on our experience
  of performing low-degree seismology on the Sun.

Title: Deeply Penetrating Banded Zonal Flows in the Solar Convection
    Zone
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R. W.;
   Larsen, R. M.; Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2000ApJ...533L.163H
Altcode: 2000astro.ph..3121H
  Helioseismic observations have detected small temporal variations
  of the rotation rate below the solar surface that correspond to the
  so-called ``torsional oscillations'' known from Doppler measurements of
  the surface. These appear as bands of slower- and faster-than-average
  rotation moving equatorward. Here we establish, using complementary
  helioseismic observations over 4 yr from the GONG network and from
  the MDI instrument on board SOHO, that the banded flows are not
  merely a near-surface phenomenon: rather, they extend downward at
  least 60 Mm (some 8% of the total solar radius) and thus are evident
  over a significant fraction of the nearly 200 Mm depth of the solar
  convection zone.

Title: Solar shear flows deduced from helioseismic dense-pack
    samplings of ring diagrams
Authors: Haber, D. A.; Hindman, B. W.; Toomre, J.; Bogart, R. S.;
   Thompson, M. J.; Hill, F.
Bibcode: 2000SoPh..192..335H
Altcode:
  We report on large-scale horizontal flows in the solar convection zone
  and their variability in time and space using a local-helioseismology
  technique known as ring-diagram analysis. By performing this analysis
  on a dense mosaic of individual regions on the solar disk, i.e.,
  a `Dense-Pack' sampling, and repeating the analysis periodically on
  several time scales, we are able to assess the variation of horizontal
  flows from day-to-day, week-to-week, and year-to-year. We find that
  although there are changes in the flows on all these time scales,
  there are also basic patterns that persist. On a daily time scale we
  observe that the flow is reduced in those areas which are occupied
  by large active regions. On somewhat longer time-scales we see bands
  of persistent fast and slow zonal flow that are identifiable as
  torsional oscillations. As we examine these bands during a series of
  years, we find that these bands migrate toward the equator as solar
  activity increases. Similarly, the latitudes at which the meridional
  flow reaches maximum follow these regions of fast zonal flow as they
  migrate equatorwards. These Dense-Pack samplings also reveal substantial
  differences in the zonal and meridional flow patterns in the northern
  and southern hemispheres.

Title: Time Variability of Rotation in Solar Convection Zone From
    soi-mdi
Authors: Toomre, J.; Christensen-Dalsgaard, J.; Howe, R.; Larsen,
   R. M.; Schou, J.; Thompson, M. J.
Bibcode: 2000SoPh..192..437T
Altcode:
  The variation of rotation in the convection zone over a period of two
  years from mid-1996 is studied using inversions of SOI-MDI data. We
  confirm the existence of near-surface banded zonal flows migrating
  towards the equator from higher latitudes, and reveal that these banded
  flows extend substantially beneath the surface, possibly to depths
  as great as 70 Mm (10% of the solar radius). Our results also reveal
  apparently significant temporal variations in the rotation rate at
  high latitudes and in the vicinity of the tachocline over the period
  of study.

Title: Dynamic Variations at the Base of the Solar Convection Zone
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R. W.;
   Larsen, R. M.; Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 2000Sci...287.2456H
Altcode:
  We have detected changes in the rotation of the sun near the base of
  its convective envelope, including a prominent variation with a period
  of 1.3 years at low latitudes. Such helioseismic probing of the deep
  solar interior has been enabled by nearly continuous observation of
  its oscillation modes with two complementary experiments. Inversion of
  the global-mode frequency splittings reveals that the largest temporal
  changes in the angular velocity Ω are of the order of 6 nanohertz
  and occur above and below the tachocline that separates the sun's
  differentially rotating convection zone (outer 30% by radius) from
  the nearly uniformly rotating deeper radiative interior beneath. Such
  changes are most pronounced near the equator and at high latitudes and
  are a substantial fraction of the average 30-nanohertz difference in Ω
  with radius across the tachocline at the equator. The results indicate
  variations of rotation close to the presumed site of the solar dynamo,
  which may generate the 22-year cycles of magnetic activity.

Title: Helioseismic detection of temporal variations of solar rotation
    rate near the base of the convection zone
Authors: Howe, R.; Christensen-Dalsgaard, J.; Hill, F.; Komm, R. W.;
   Larsen, R. M.; Schou, J.; Thompson, M. J.; Toomre, J.
Bibcode: 1999AAS...19510702H
Altcode: 1999BAAS...31R1530H
  The differential rotation of the Sun and its ability to generate
  large-scale magnetic fields through cyclic dynamo action appear to be
  intimately linked. It is now commonly thought that the global dynamo
  behavior responsible for the emergence of active regions is derived
  from strong organized toroidal magnetic fields generated by rotational
  shear in a thin region (the tachocline) at the base of the convection
  zone. The magnetic field could well have a feedback effect on the fluid
  motions in the region. We are thus motivated to use helioseismology
  to look for changes in rotation profiles near the tachocline as the
  Sun's magnetic cycle progresses. This approach has become possible
  using frequency-splitting data for p- and f-mode oscillations derived
  over four years (from May 1995 to Sept 1999) of full-disk Doppler
  observations from the ground-based Global Oscillation Network Group
  (GONG) project and from the Michelson Doppler Imager (MDI) experiment
  aboard the SOHO spacecraft. Inversions using two different methods of
  the splittings from these two independent data sets reveal systematic
  variations of the rotation rate close to the base of the convection
  zone, with different behavior at low and high latitudes. Notable
  are variations of order 6 nHz in rotation rates near the equator,
  to be compared with the radial angular velocity contrast across the
  tachocline of about 30 nHz. These exhibit several nearly repetitive
  changes with a period of about 1.2-1.4 years and appear to be real
  changes in the deep convection zone and tachocline rotation rates that
  need to be followed as the solar cycle progresses. The GONG project is
  managed by the National Solar Observatory, a Division of the National
  Optical Astronomy Observatories, which is operated by AURA, Inc. under
  a cooperative agreement with the National Science Foundation. SOHO is
  a joint project of ESA and NASA.

Title: Helioseismic Constraints on the Structure of the Solar
    Tachocline
Authors: Charbonneau, P.; Christensen-Dalsgaard, J.; Henning, R.;
   Larsen, R. M.; Schou, J.; Thompson, M. J.; Tomczyk, S.
Bibcode: 1999ApJ...527..445C
Altcode:
  This paper presents a series of helioseismic inversions aimed at
  determining with the highest possible confidence and accuracy the
  structure of the rotational shear layer (the tachocline) located
  beneath the base of the solar convective envelope. We are particularly
  interested in identifying features of the inversions that are robust
  properties of the data, in the sense of not being overly influenced
  by the choice of analysis methods. Toward this aim we carry out
  two types of two-dimensional linear inversions, namely Regularized
  Least-Squares (RLS) and Subtractive Optimally Localized Averages
  (SOLA), the latter formulated in terms of either the rotation rate or
  its radial gradient. We also perform nonlinear parametric least-squares
  fits using a genetic algorithm-based forward modeling technique. The
  sensitivity of each method is thoroughly tested on synthetic data. The
  three methods are then used on the LOWL 2 yr frequency-splitting
  data set. The tachocline is found to have an equatorial thickness
  of w/R<SUB>solar</SUB>=0.039+/-0.013 and equatorial central radius
  r<SUB>c</SUB>/R<SUB>solar</SUB>=0.693+/-0.002. All three techniques
  also indicate that the tachocline is prolate, with a difference in
  central radius Δr<SUB>c</SUB>/R<SUB>solar</SUB>~=0.024+/-0.004 between
  latitude 60° and the equator. Assuming uncorrelated and normally
  distributed errors, a strictly spherical tachocline can be rejected
  at the 99% confidence level. No statistically significant variation
  in tachocline thickness with latitude is found. Implications of these
  results for hydrodynamical and magnetohydrodynamical models of the
  solar tachocline are discussed.

Title: Rotation of the solar interior
Authors: Christensen-Dalsgaard, Jørgen; Thompson, Michael J.
Bibcode: 1999CSci...77.1460C
Altcode:
  No abstract at ADS

Title: Effects of line asymmetries on the determination of solar
    internal structure
Authors: Rabello-Soares, M. C.; Christensen-Dalsgaard, J.; Rosenthal,
   C. S.; Thompson, M. J.
Bibcode: 1999A&A...350..672R
Altcode: 1999astro.ph..8250R
  Despite the strong evidence that the peaks in the spectrum of solar
  oscillations are asymmetric, most determinations of mode frequencies
  have been based on fits of symmetric Lorentzian profiles to the Fourier
  or power spectra of oscillation time strings. The systematic errors
  resulting from neglecting the line asymmetry could have serious effects
  on inversions for the solar internal structure and rotation. Here we
  analyse artificial data based on simple models of the intrinsic line
  asymmetry, using GONG mode parameters with asymmetries found by one
  of us (Rosenthal \cite{rosenthal2}). By fitting Lorentzians to the
  resulting spectra, we estimate the likely properties of the errors
  introduced in the frequencies. We discuss whether these frequency
  shifts have a form similar to the near-surface layers uncertainties
  and are therefore suppressed in the solar structure inversion. We also
  estimate directly their contribution, if any, in the solar sound-speed
  and density determinations using the SOLA technique.

Title: A note on Saio's estimate of second-order effects of rotation
    on stellar oscillation frequencies
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1999A&A...350..852C
Altcode:
  In many cases, oscillating stars rotate so rapidly that second-order
  effects must be taken into account in analyses of the oscillation
  frequencies. Such investigations have commonly been based on results
  provided by Saio (1981) for a polytropic model. Here we compare those
  with frequency changes for more realistic models; we point out that
  a simple correction to Saio's data allows them to be used in the
  observationally relevant case of comparing models at fixed luminosity
  and effective temperature.

Title: Rotation of the solar core from BiSON and LOWL frequency
    observations
Authors: Chaplin, W. J.; Christensen-Dalsgaard, J.; Elsworth, Y.;
   Howe, R.; Isaak, G. R.; Larsen, R. M.; New, R.; Schou, J.; Thompson,
   M. J.; Tomczyk, S.
Bibcode: 1999MNRAS.308..405C
Altcode:
  Determination of the rotation of the solar core requires very accurate
  data on splittings for the low-degree modes which penetrate to the core,
  as well as for modes of higher degree to suppress the contributions
  from the rest of the Sun to the splittings of the low-degree modes. Here
  we combine low-degree data based on 32 months of observations with the
  BiSON network and data from the LOWL instrument. The data are analysed
  with a technique that specifically aims at obtaining an inference of
  rotation that is localized to the core. Our analysis provides what we
  believe is the most stringent constraint to date on the rotation of
  the deep solar interior.

Title: Strange baryon production in p-Pb collisions at 158 GeV
img1.gif: a comparison with VENUS model
Authors: Virgili, T.; WA97 Collaboration; Andersen, E.; Antinori,
   F.; Armenise, N.; Bakke, H.; Bán, J.; Barberis, D.; Beker, H.;
   Beusch, W.; Bloodworth, I. J.; Böhm, J.; Caliandro, R.; Campbell,
   M.; Cantatore, E.; Carrer, N.; Catanesi, M. G.; Chesi, E.; Dameri,
   M.; Darbo, G.; Diaczek, A.; Di Bari, D.; Di Liberto, S.; Earl, B. C.;
   Elia, D.; Evans, D.; Fanebust, K.; Fini, R. A.; Fontaine, J. C.;
   Ftácnik, J.; Ghidini, B.; Grella, G.; Guida, M.; Heijne, E. H. M.;
   Helstrup, H.; Holme, A. K.; Huss, D.; Jacholkowski, A.; Jones,
   G. T.; Jovanovic, P.; Jusko, A.; Kachelhoffer, T.; Kinson, J. B.;
   Kirk, A.; Klempt, W.; Knudsen, B. T. H.; Knudson, K.; Králik, I.;
   Lenti, V.; Lietava, R.; Loconsole, R. A.; Løvhøiden, G.; Lupták,
   M.; Mack, V.; Manzari, V.; Martinengo, P.; Mazzoni, M. A.; Meddi, F.;
   Michalon, A.; Michalon-Mentzer, M. E.; Middelkamp, P.; Morando, M.;
   Muciaccia, M. T.; Nappi, E.; Navach, F.; Norman, P. I.; Osculati,
   B.; Pastircák, B.; Pellegrini, F.; Piska, K.; Posa, F.; Quercigh,
   E.; Ricci, R. A.; Romano, G.; Rosa, G.; Rossi, L.; Rotscheidt, H.;
   Safarik, K.; Saladino, S.; Salvo, C.; Sándor, L.; Scognetti, T.;
   Segato, G.; Sené, M.; Sené, R.; Simone, S.; Snoeys, W.; Staroba,
   P.; Szafran, S.; Thompson, M.; Thorsteinsen, T. F.; Tomasicchio, G.;
   Torrieri, G. D.; Tveter, T. S.; Urbán, J.; Venables, M.; Villalobos
   Baillie, O.; Virgili, T.; Volte, A.; Votruba, M. F.; Závada, P.
Bibcode: 1999JPhG...25..345V
Altcode:
  img2.gif, img3.gif, and img4.gif yields measured by the WA97 experiment
  at central rapidity in p-Pb interactions at 158 GeV/c are compared to
  those predicted by VENUS 4.12. The VENUS model, although in reasonable
  agreement with the img2.gif and the negative particle data, fails to
  reproduce the data on multistrange baryons and anti-baryons.

Title: Time-Variability of the Inferred Rotation in the Upper
    Convection Zone
Authors: Toomre, J.; Christensen-Dalsgaard, J.; Howe, R.; Larsen,
   R. M.; Schou, J.; Thompson, M. J.
Bibcode: 1999soho....9E..87T
Altcode:
  We present results of inverting for the rotation of the upper convection
  zone, using frequency splittings derived from successive 72-day time
  series of SOI-MDI observations. Schou (1999; also Schou et al. 1998)
  has studied the evolution of the pattern of small-scale zonal flows
  in the near-surface layers using f-mode splittings and has found that
  this flow pattern migrates equatorward in a manner similar to that seen
  in the so-called torsional oscillation observed in surface Doppler
  measurements. In the present work we look at the time variability
  of the rotation at greater depth, in the upper convection zone, by
  inverting both f- and p-mode splittings. The evolution of the flow is
  less regular than is seen at the surface, but we do observe apparently
  significant variations in the inferred flow pattern, on latitudinal
  scales similar to those seen at the surface. In particular, in the
  subsurface shear layer we see intriguing variations, with the first
  year's data showing apparent emergence of zonal flows of some 10-15
  m/s amplitude at around 20 degrees latitude.

Title: Convective Envelopes in Solar-Type Stars: What Can We Learn
    from their Seismic Study?
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1999ASPC..173..273M
Altcode: 1999sstt.conf..273M
  No abstract at ADS

Title: Simulation of Wave Fields to Assess the Sensitivity of
    Ring-Diagram Analyses to Shearing Flows
Authors: Hindman, B. W.; Gough, D. O.; Haber, D. A.; Thompson, M. J.;
   Toomre, J.
Bibcode: 1999soho....9E..64H
Altcode:
  Ring-diagram analyses of acoustic-wave distortion by flows map
  horizontal motions within the solar convection beneath the localized
  regions where the observations are taken. To leading order, the
  flow field responsible for the advection of waves is taken to be
  horizontally uniform across the region. Current ring-diagram analyses
  are only carried out to this order, although in reality the flow
  is likely to vary across the local patch of the Sun. It is crucial
  for the interpretation of the results of ring-diagram analyses that
  the effects of shearing flows be assessed. Furthermore, the present
  analyses ignore any influence on the ring parameters of flows exterior
  to the region being studied. We present a progress report on the
  forward calculation of the modification of ring parameters produced
  by spatially varying flow fields. We examine effects of flow fields
  both inside and outside the region of observation. Additionally,
  we assess the influence of the non-uniform flow on the maps of the
  velocity field obtained by inverting the ring-parameter data. The
  effect of the inhomogeneous flow can be studied as a scattering
  problem. We have developed Green functions connecting an underlying
  inhomogeneous horizontal flow to the scattered wave field that results
  when an incident plane wave encounters the flow. By considering an
  ensemble of such incident waves, ring parameters can be inferred from
  the wave field. One application is to analyze artificial data sets,
  computed from models that contain horizontal shear flows. The scattered
  wave field produced by a prescribed 3-D shearing flow is computed,
  and the original and scattered wave fields are combined to generate an
  artificial helioseismic data set. The artificial data so produced should
  then be passed through a ring-diagram analysis and the deduced velocity
  field compared to the known imposed flow. Another application is to
  compute 3-D kernels relating the ring parameters to the underlying flow:
  these will in the future permit 3-D inversions for the flows within
  the solar convection zone, using mosaics of many ring-diagram samplings.

Title: Helioseismic Studies of Differential Rotation in the Solar
    Envelope by the Solar Oscillations Investigation Using the Michelson
    Doppler Imager
Authors: Schou, J.; Antia, H. M.; Basu, S.; Bogart, R. S.; Bush,
   R. I.; Chitre, S. M.; Christensen-Dalsgaard, J.; Di Mauro, M. P.;
   Dziembowski, W. A.; Eff-Darwich, A.; Gough, D. O.; Haber, D. A.;
   Hoeksema, J. T.; Howe, R.; Korzennik, S. G.; Kosovichev, A. G.;
   Larsen, R. M.; Pijpers, F. P.; Scherrer, P. H.; Sekii, T.; Tarbell,
   T. D.; Title, A. M.; Thompson, M. J.; Toomre, J.
Bibcode: 1998ApJ...505..390S
Altcode:
  The splitting of the frequencies of the global resonant acoustic modes
  of the Sun by large-scale flows and rotation permits study of the
  variation of angular velocity Ω with both radius and latitude within
  the turbulent convection zone and the deeper radiative interior. The
  nearly uninterrupted Doppler imaging observations, provided by the
  Solar Oscillations Investigation (SOI) using the Michelson Doppler
  Imager (MDI) on the Solar and Heliospheric Observatory (SOHO) spacecraft
  positioned at the L<SUB>1</SUB> Lagrangian point in continuous sunlight,
  yield oscillation power spectra with very high signal-to-noise ratios
  that allow frequency splittings to be determined with exceptional
  accuracy. This paper reports on joint helioseismic analyses of
  solar rotation in the convection zone and in the outer part of the
  radiative core. Inversions have been obtained for a medium-l mode set
  (involving modes of angular degree l extending to about 250) obtained
  from the first 144 day interval of SOI-MDI observations in 1996. Drawing
  inferences about the solar internal rotation from the splitting data
  is a subtle process. By applying more than one inversion technique
  to the data, we get some indication of what are the more robust
  and less robust features of our inversion solutions. Here we have
  used seven different inversion methods. To test the reliability and
  sensitivity of these methods, we have performed a set of controlled
  experiments utilizing artificial data. This gives us some confidence
  in the inferences we can draw from the real solar data. The inversions
  of SOI-MDI data have confirmed that the decrease of Ω with latitude
  seen at the surface extends with little radial variation through much
  of the convection zone, at the base of which is an adjustment layer,
  called the tachocline, leading to nearly uniform rotation deeper
  in the radiative interior. A prominent rotational shearing layer in
  which Ω increases just below the surface is discernible at low to
  mid latitudes. Using the new data, we have also been able to study the
  solar rotation closer to the poles than has been achieved in previous
  investigations. The data have revealed that the angular velocity
  is distinctly lower at high latitudes than the values previously
  extrapolated from measurements at lower latitudes based on surface
  Doppler observations and helioseismology. Furthermore, we have found
  some evidence near latitudes of 75° of a submerged polar jet which
  is rotating more rapidly than its immediate surroundings. Superposed
  on the relatively smooth latitudinal variation in Ω are alternating
  zonal bands of slightly faster and slower rotation, each extending
  some 10° to 15° in latitude. These relatively weak banded flows
  have been followed by inversion to a depth of about 5% of the solar
  radius and appear to coincide with the evolving pattern of ``torsional
  oscillations'' reported from earlier surface Doppler studies.

Title: A strategy for fitting partially blended ridges in GONG solar
    p-mode spectra
Authors: Howe, R.; Thompson, M. J.
Bibcode: 1998A&AS..131..539H
Altcode:
  Observations of solar oscillations by the Global Oscillation Network
  Group (GONG) using a network of telescopes deployed around the Earth
  eliminate temporal aliases from the oscillation power spectra to a
  very substantial extent, making the measurement of oscillation mode
  parameters much cleaner than with single-site observations. However,
  the problem of spatial aliasing, which arises from the fact that we see
  only one side of the Sun, still causes some problems. We discuss some
  of the issues affecting the estimation of medium-l solar acoustic mode
  parameters from the data obtained by the GONG network, and in particular
  the contamination by spatial leakage. We determine the areas in the
  l-nu plane in which such leakage is a problem, and finally we describe
  a method for improving the mode frequency estimation in such regions,
  thus extending the range of modes for which useful frequency estimates
  can be obtained.

Title: The Rotation of the Solar Core Inferred by Genetic Forward
    Modeling
Authors: Charbonneau, P.; Tomczyk, S.; Schou, J.; Thompson, M. J.
Bibcode: 1998ApJ...496.1015C
Altcode:
  Genetic forward modeling is a genetic algorithm-based modeling technique
  that can be used to perform helioseismic inversions of the Sun's
  internal angular velocity profile. The method can easily accommodate
  constraints such as positivity and monotonicity and readily lends itself
  to the use of robust statistical goodness-of-fit estimators. After
  briefly describing the technique, we ascertain its performance
  by carrying out a series of inversions for artificial splitting
  data generated from a set of synthetic internal rotation profiles
  characterized by various small inward increases in angular velocity in
  the deep solar core (r/R<SUB>⊙</SUB> &lt;= 0.5). These experiments
  indicate that the technique is accurate down to r/R<SUB>⊙</SUB>
  ~= 0.2, and retains useful sensitivity down to r/R<SUB>⊙</SUB> ~=
  0.1. <P />We then use genetic forward modeling in conjunction with the
  LOW degree L (LOWL) 2 year frequency-splitting data set to determine
  the rotation rate in the deep solar core. We perform a large set
  of one-dimensional and 1.5-dimensional inversions using regularized
  least-squares minimization, conventional least-squares minimization
  with a monotonicity constraint (∂Ω/∂r &lt;= 0), and inversions
  using robust statistical estimators. These calculations indicate that
  the solar core rotates very nearly rigidly down to r/R<SUB>⊙</SUB> ~
  0.1. More specifically, on spatial scales &gt;~0.04 R<SUB>⊙</SUB> we
  can rule out inward increases by more than 50% down to r/R<SUB>⊙</SUB>
  = 0.2, and by more than a factor of 2 down to r/R<SUB>⊙</SUB> =
  0.1. Thorough testing of various possible sources of bias associated
  with our technique indicates that these results are robust with respect
  to intrinsic modeling assumptions. Consequences of our results for
  models of the rotational evolution of the Sun and solar-type stars
  are discussed.

Title: Slow Poles and Shearing Flows from Heliospheric Observations
    with MDI and GONG Spanning a Year
Authors: Schou, J.; Christensen-Dalsgaard, J.; Howe, R.; Larsen,
   R. M.; Thompson, M. J.; Toomre, J.
Bibcode: 1998ESASP.418..845S
Altcode: 1998soho....6..845S
  We invert one year of coeval high-resolution rotational splitting data
  (up to degree l 250) from GONG and SOI-MDI. The first 4 months of
  MDI data uncovered several new features in the rotation of the solar
  convective envelope: surface and subsurface zonal bands corresponding
  to the so-called torsional oscillations, superimposed on the overall
  smooth latitudinal surface rotation; a drop in the near-polar surface
  rotation rate below the rate extrapolated from lower latitudes; and an
  indication of a prograde jet-like feature at high latitudes at a depth
  of about 5 percent of the solar radius. Using the 1 year of data from
  the MDI and GONG instruments, we test the robustness and stationarity of
  these features. As an aid to testing the robustness of our inferences,
  we use two independent inversion methods (2-D regularized least squares
  and SOLA) and apply them to the splitting data obtained from both GONG
  and MDI.

Title: Seismic Constraints on Sound Speed in the Solar Core
Authors: Rabello-Soares, M. C.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1998ESASP.418..511R
Altcode: 1998soho....6..511R
  Direct seismic information about the structure of the solar core from
  measured p-mode frequencies is based on only a modest number of modes
  of low degree. Hence it is difficult to obtain local measures of,
  for example, the variation of the sound speed in the core. However,
  even averages of the central sound-speed difference between the Sun
  and a model would be of considerable diagnostic value, provided that
  these averages could be effectively restricted to a sufficiently
  small region. Chaplin et al. (1998) developed a technique, based on
  the method of optimally localized averages introduced by Backus &amp;
  Gilbert, to construct an average of the rotation of the solar core,
  and this was applied with some success to combined BiSON and LOWL
  data. Here we investigate a similar procedure for constructing averages
  of the sound-speed difference between the Sun and a reference model,
  localized to the core. These provide seismic constraints on core
  structure that are only minimally sensitive to uncertainties in other
  regions of the Sun.

Title: The Base of the Convection Zone and the Solar Magnetic Cycle:
    Seismic Detection of Their Connection
Authors: Monteiro, Mario J. P. F. G.; Christensen-Dalsgaard, Jorgen;
   Thompson, Michael J.
Bibcode: 1998ESASP.418..495M
Altcode: 1998soho....6..495M
  It is now possible to detect small variations with time of the
  characteristics of the transition at the bottom of the solar convection
  zone, as determined from the periodic signal in the frequencies
  (Christensen-Dalsgaard et.al. 1995, Basu 1997). Such measurements may
  allow us to establish whether and in what manner the deeper convection
  zone changes with the solar magnetic cycle. This would be important
  for understanding the dynamics at the base of the convection zone and
  the origin of the solar cycle. It will also help in understanding
  the physics of convective overshoot, its interaction with rotation
  and magnetic fields, and the effects on the stratification. In this
  work we investigate the limits on the detectability of small changes
  in the stratification at the base of the convection zone, and attempt
  to constrain the amplitude of the changes from currently available
  seismic data.

Title: On the seismic signature of the HeII ionization zone in
    stellar envelopes
Authors: Monteiro, M. J. P. F. G.; Thompson, M. J.
Bibcode: 1998IAUS..185..317M
Altcode:
  The method developed for the seismic measurement of convective overshoot
  (Christensen-Dalsgaard et al 1995, MNRAS 276, 283) can be extended in
  order to study the layer where the second ionization of helium takes
  place in a star's envelope. Because this zone is confined to a very thin
  region the effects on the structure can be treated as the result of a
  localized perturbation to an otherwise smooth behaviour. Therefore,
  we may hope to be able to use the characteristic periodic signal
  in the frequencies of oscillation, arising from such a localized
  perturbation, to determine important aspects of this region. In this
  poster we present the theoretical analysis of such a signal showing
  how its different characteristics are associated with the different
  physical aspects contributing for the zone of the second ionization
  of helium. Some of these aspects we consider are the envelope helium
  abundance and the properties of the equation of state (EOS). In this
  way we attempt to establish how such a characteristic signal can be
  used to study seismologically the Sun and other stars.

Title: Asteroseismology and Stellar Rotation
Authors: Kjeldsen, H.; Arentoft, T.; Bedding, T.;
   Christensen-Dalsgaard, J.; Frandsen, S.; Thompson, M. J.
Bibcode: 1998ESASP.418..385K
Altcode: 1998soho....6..385K
  Δ Scuti stars are observed to rotate with surface velocities of the
  order 100-200 km/s corresponding to a rotation period of about one
  day. Rotation removes the frequency degeneracy in the azimuthal order m
  of the modes and thus allows the possibility of determining the angular
  velocity inside the star. Rotation also perturbs the internal structure
  of the star, making the star oblate, as well as changing the internal
  stratification. Such perturbations will result in a systematic change of
  all frequencies, if compared with a non-rotating star of similar mass
  and age. In this way even the radial (l = 0) mode frequencies will be
  affected by the rotation of the star. We discuss how basic properties
  as well as frequencies of δ Scuti stars are affected by fast rotation
  and we investigate the impact of these changes on our interpretation
  of observed frequencies used in an asteroseismic analysis. We discuss
  the results in the light of the currently available frequency data
  for δ Scuti stars in the Praesepe cluster.

Title: Looking for Variations with Latitude of the Base of the Solar
    Convection Zone
Authors: Monteiro, M. J. P. F. G.; Thompson, M. J.
Bibcode: 1998ESASP.418..819M
Altcode: 1998soho....6..819M
  The Sun's m-averaged frequencies of global oscillations have been used
  successfully in determining the basic characteristics of the base of the
  solar convective region (e.g. Christensen-Dalsgaard et.al. 1995, Basu
  1997). In particular, it has been possible to constrain its location
  and more particularly the extent of convective overshoot. With higher
  quality data now available it is becoming possible to isolate the
  properties of this region at different latitudes. This is important
  for the modelling aspects such as mixing and convective overshoot
  occurring at the base of the convection zone. It can also have
  interesting interplay with the rotation profile around the region of
  the tachocline and the generation of magnetic fields. Such properties
  as deeper penetration of the convection at certain latitudes may be
  intimately connected with the angular velocity profile there, and the
  identification of such characteristics in the thermal stratification
  is therefore important to complement the information from the rotation
  inversions (Schou et al. 1998). Here we present an analysis of SOI--MDI
  data to try to detect such latitudinal variations.

Title: Space Asteroseismology on Later-type Stars
Authors: Roxburgh, Ian W.; Thompson, Michael J.
Bibcode: 1998Ap&SS.261...13R
Altcode: 1999Ap&SS.261...13R
  No abstract at ADS

Title: Inversion Methods
Authors: Thompson, M. J.
Bibcode: 1998IAUS..185..125T
Altcode:
  No abstract at ADS

Title: What We Have Learned from Helioseismology
Authors: Thompson, Michael J.
Bibcode: 1998Ap&SS.261...23T
Altcode: 1999Ap&SS.261...23T
  The Sun's global oscillations, which are studied both in spatially
  unresolved ("Sun-as-a-star") and resolved observations of the
  solar disk, have enabled helioseismology to probe in detail the
  solar interior. I review first what is learned from the unresolved
  measurements, since this gives an idea of what we may in the not too
  distant future be able to learn about the interiors of other stars
  undergoing solar-type oscillations. I then look at the main results
  from resolved observations, which have begun to reveal the structure
  and dynamics of the interior of a star in exquisite detail.

Title: Effects of Line Asymmetries on the Determination of Solar
    Oscillation Frequencies
Authors: Christensen-Dalsgaard, J.; Rabello-Soares, M. C.; Rosenthal,
   C. S.; Thompson, M. J.
Bibcode: 1998ESASP.418..147C
Altcode: 1998soho....6..147C
  Despite the strong evidence that the peaks in the spectrum of solar
  oscillations are asymmetric, most determinations of mode frequencies
  have been based on fits of symmetric Lorentzian profiles to the Fourier
  or power spectra of oscillation time strings. The systematic errors
  resulting from neglecting the line asymmetry could have serious effects
  on inversions for the solar internal structure and rotation. Here we
  analyze artificial data based on simple models of the intrinsic line
  asymmetry. By fitting Lorentzians to the resulting spectra, we estimate
  the likely properties of the errors introduced in the frequencies and
  consider the possible effects on the inversions.

Title: Seismic detection of boundaries of stellar convective regions
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1998IAUS..185..315M
Altcode:
  The seismic study of the base of the convection zone in the Sun (eg
  Christensen-Dalsgaard et al 1995, MNRAS 276, 283) has been successful
  in determining not only the position of the base of the convective
  envelope, but also the characteristics of this transition layer. In
  this poster we consider other types of star possessing convective
  envelopes or cores and seek to establish the conditions under which we
  may determine important characteristics of their convective regions. In
  particular we may hope to establish seismologically that a star does
  indeed posess a convective envelope or core and to measure the size
  of that convective region. The method used consists in identifying a
  signal in the observed frequencies whose characteristics depend on
  the location of the border of a convective region in the star. The
  limitations in terms of observational uncertainties and stellar
  characteristics are presented.

Title: Detection of the Lower Boundary of Stellar Convective Envelopes
    from Seismic Data
Authors: Monteiro, Mário J. P. F. G.; Christensen-Dalsgaard, Jørgen;
   Thompson, Michael J.
Bibcode: 1998Ap&SS.261...41M
Altcode: 1999Ap&SS.261...41M
  No abstract at ADS

Title: Diagnostic Potential of the Solar f Modes
Authors: Chitre, S. M.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1998ESASP.418..141C
Altcode: 1998soho....6..141C
  The frequencies of f modes of intermediate and high degree l of a
  stellar model in hydrostatic equilibrium are essentially given by ω
  = square root {g k<SUB>h</SUB>}, where to a good first approximation
  g is the surface gravitational acceleration G M / R<SUP>2</SUP> and
  k<SUB>h</SUB> = square root {l(l+1)}/R, M and R being the mass and
  radius respectively of the model. More precisely, the frequency is
  determined not simply by the surface values of these quantities but
  by a weighted average over the region where the mode has appreciable
  amplitude. Thus the frequencies of the f modes depend on the density
  stratification in the near-surface region (Gough 1985, 1993). Given
  the very high accuracy to which the f-mode frequencies can now
  be determined, in particular from the SOI/MDI experiment on SOHO,
  this sensitivity may provide an important diagnostic of the Sun's
  near-surface structure. We investigate this sensitivity, in terms of
  numerical kernels and the simple analytical approximation derived by
  Gough. In addition, we consider the possibilities for investigating
  time variations and asphericity in solar structure on the basis of
  f-mode observations.

Title: The SOI-MDI High-Latitude Jet: the Evidence For and Against
Authors: Howe, R.; Antia, H.; Basu, S.; Christensen-Dalsgaard, J.;
   Korzennik, S. G.; Schou, J.; Thompson, M. J.
Bibcode: 1998ESASP.418..803H
Altcode: 1998soho....6..803H
  The apparent detection of a prograde jet at latitude 75-circ and at a
  radius of about 0.95R<SUB>odot</SUB> in some inversions of rotation data
  from SOI--MDI (Schou et al., 1998) has excited considerable interest,
  but whether the jet really exists in the solar interior is certainly not
  yet firmly established. The detection of the feature is sensitive both
  to the inversion techniques used and to the methods of mode parameter
  estimation used to generate the input data. In particular, the feature
  is much more apparent in Regularized Least-Squares inversions than
  in inversions using an Optimally Localized Average approach, and is
  not detected at all in the present GONG data when analysed with the
  GONG peakfinding algorithm, or indeed in SOI data when analysed with
  the GONG algorithm. Therefore in this poster we examine critically
  the current evidence for the source and existence of this jet in the
  light of forward and inverse analyses.

Title: Solar internal sound speed as inferred from combined BiSON
    and LOWL oscillation frequencies
Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Chaplin, W. J.;
   Elsworth, Y.; Isaak, G. R.; New, R.; Schou, J.; Thompson, M. J.;
   Tomczyk, S.
Bibcode: 1997MNRAS.292..243B
Altcode: 1997astro.ph..2105B
  Observations of the Sun with the LOWL instrument provide a homogeneous
  set of solar p-mode frequencies from low to intermediate degree that
  allow one to determine the structure of much of the solar interior
  avoiding systematic errors that are introduced when different data sets
  are combined, i.e., principally the effects of solar cycle changes on
  the frequencies. Unfortunately, the LOWL data set contains very few of
  the lowest-degree modes, which are essential for determining reliably
  the structure of the solar core - in addition, these lowest-degree data
  have fairly large associated uncertainties. However, observations made
  by the Birmingham Solar-Oscillations Network (BiSON) in integrated
  sunlight provide high-accuracy measurements of a large number of
  low-degree modes. In this paper we demonstrate that the low-degree mode
  set of the LOWL data can be successfully combined with the more accurate
  BiSON data, provided the observations are contemporaneous for those
  frequencies where the solar cycle induced effects are important. We
  show that this leads to a factor of 2 decrease in the error on the
  inferred sound speed in the solar core. We find that the solar sound
  speed is higher than in solar models for r&lt;0.2Rsolar. The density
  of the solar core is, however, lower than that in solar models.

Title: Rotation and Zonal Flows in the Solar Envelope from the
    SOHO/MDI Observations
Authors: Scherrer, P. H.; Schou, J.; Bogart, R. S.; Bush, R. I.;
   Hoeksema, J. T.; Kosovichev, A. G.; Antia, H. M.; Chitre, S. M.;
   Christensen-Dalsgaard, J.; Larsen, R. M.; Pijpers, F. P.; Eff-Darwich,
   A.; Korzennik, S. G.; Gough, D. O.; Sekii, T.; Howe, R.; Tarbell,
   T.; Title, A. M.; Thompson, M. J.; Toomre, J.
Bibcode: 1997AAS...191.7310S
Altcode: 1997BAAS...29.1322S
  We report on the latest inferences concerning solar differential
  rotation that have been drawn from the helioseismic data that are now
  available from the Solar Oscillations Investigation (SOI) using the
  Michelson Doppler Imager (MDI) on the Solar and Heliospheric Observatory
  (SOHO). That spacecraft is positioned in a halo orbit near the Sun-Earth
  Lagrangian point L_1, in order to obtain continuous Doppler-imaged
  observations of the sun with high spatial fidelity. Doppler velocity,
  intensity and magnetic field images are recorded, based on modulations
  of the 676.8 nm Ni I solar absorption line. The high spatial resolution
  of MDI thereby permits the study of many millions of global resonant
  modes of solar oscillation. Determination and subsequent inversion
  of the frequencies of these modes, including the degeneracy-splitting
  by the rotation of the sun, enables us to infer how the sun's angular
  velocity varies throughout much of the interior. The current MDI data
  are providing substantial refinements to the helioseismic deductions
  that can be made about differential rotation both within the convection
  zone and in its transition to the radiative interior. The shearing
  layer evident in the angular velocity Omega just below the solar
  surface is becoming better defined, as is the adjustment layer or
  tachocline near the base of the convection zone. The MDI data are also
  revealing a prominent decrease in Omega at high latitudes from the
  rotation rate expressed by a simple three-term expansion in latitude
  that was originally deduced from surface Doppler measurements. Further,
  there are indications that a submerged polar vortex involving somewhat
  faster Omega than its surroundings exists at about 75(deg) in latitudes.

Title: SVD preprocessing of helioseismic data for solar structure
    inversion.
Authors: Basu, S.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1997A&A...321..634B
Altcode:
  Helioseismic inversion to determine solar structure is based on the
  analysis of very substantial numbers of modes and hence may involve
  considerable computational expense. This is particularly true for
  inversions using methods of optimally localised averages, which
  require inversion of matrices whose order is the number of modes in
  the set; yet such methods are desirable to make the full use of the
  data. On the other hand, there is considerable redundancy in the
  data, different modes carrying almost the same information about
  solar structure. Thus, in the unavoidable presence of data errors,
  the number of independent pieces of information is generally much
  less than the number of modes. This suggests that the mode-set can
  be reduced by forming suitable combinations of the data before the
  more computationally intensive inversion is performed. We show that
  such combinations may be based on singular value decomposition (SVD)
  of the problem, leading to a drastically reduced inverse problem whose
  solution is essentially indistinguishable from the solution of the
  original problem. In addition, the results of the SVD provide insight
  into the information content of the helioseismic data.

Title: Structure and Rotation of the Solar Interior: Initial Results
    from the MDI Medium-L Program
Authors: Kosovichev, A. G.; Schou, J.; Scherrer, P. H.; Bogart, R. S.;
   Bush, R. I.; Hoeksema, J. T.; Aloise, J.; Bacon, L.; Burnette, A.; de
   Forest, C.; Giles, P. M.; Leibrand, K.; Nigam, R.; Rubin, M.; Scott,
   K.; Williams, S. D.; Basu, Sarbani; Christensen-Dalsgaard, J.; Dappen,
   W.; Rhodes, E. J., Jr.; Duvall, T. L., Jr.; Howe, R.; Thompson, M. J.;
   Gough, D. O.; Sekii, T.; Toomre, J.; Tarbell, T. D.; Title, A. M.;
   Mathur, D.; Morrison, M.; Saba, J. L. R.; Wolfson, C. J.; Zayer, I.;
   Milford, P. N.
Bibcode: 1997SoPh..170...43K
Altcode:
  The medium-l program of the Michelson Doppler Imager instrument on board
  SOHO provides continuous observations of oscillation modes of angular
  degree, l, from 0 to ∽ 300. The data for the program are partly
  processed on board because only about 3% of MDI observations can be
  transmitted continuously to the ground. The on-board data processing,
  the main component of which is Gaussian-weighted binning, has been
  optimized to reduce the negative influence of spatial aliasing of the
  high-degree oscillation modes. The data processing is completed in a
  data analysis pipeline at the SOI Stanford Support Center to determine
  the mean multiplet frequencies and splitting coefficients. The initial
  results show that the noise in the medium-l oscillation power spectrum
  is substantially lower than in ground-based measurements. This enables
  us to detect lower amplitude modes and, thus, to extend the range of
  measured mode frequencies. This is important for inferring the Sun's
  internal structure and rotation. The MDI observations also reveal the
  asymmetry of oscillation spectral lines. The line asymmetries agree
  with the theory of mode excitation by acoustic sources localized in the
  upper convective boundary layer. The sound-speed profile inferred from
  the mean frequencies gives evidence for a sharp variation at the edge
  of the energy-generating core. The results also confirm the previous
  finding by the GONG (Gough et al., 1996) that, in a thin layer just
  beneath the convection zone, helium appears to be less abundant than
  predicted by theory. Inverting the multiplet frequency splittings from
  MDI, we detect significant rotational shear in this thin layer. This
  layer is likely to be the place where the solar dynamo operates. In
  order to understand how the Sun works, it is extremely important to
  observe the evolution of this transition layer throughout the 11-year
  activity cycle.

Title: Internal structure and rotation of the Sun: First results
    from MDI data
Authors: Kosovichev, A. G.; Schou, J.; Scherrer, P. H.; Bogart, R. S.;
   Bush, R. I.; Hoeksema, J. T.; Aloise, J.; Bacon, L.; Burnette, A.;
   De Forest, C.; Giles, P. M.; Leibrand, K.; Nigam, R.; Rubin, M.;
   Scott, K.; Williams, S. D.; Basu, Sarbani; Christensen-Dalsgaard,
   J.; Däppen, W.; Rhodes, E. J., Jr.; Duvall, T. L., Jr.; Howe, R.;
   Thompson, M. J.; Gough, D. O.; Sekii, T.; Toomre, J.; Tarbell, T. D.;
   Title, A. M.; Mathur, D.; Morrison, M.; Saba, J. L. R.; Wolfson,
   C. J.; Zayer, I.; Milford, P. N.
Bibcode: 1997IAUS..181..203K
Altcode:
  No abstract at ADS

Title: Internal rotation and dynamics of the Sun from GONG data
Authors: Korzennik, S.; Thompson, M. J.; Toomre, J.; GONG Internal
   Rotation Team
Bibcode: 1997IAUS..181..211K
Altcode:
  No abstract at ADS

Title: On solar p-mode frequency shifts caused by near-surface
    model changes
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1997MNRAS.284..527C
Altcode:
  The effect on p-mode frequencies of changing the near-surface structure
  of solar models is investigated. As is well known, changes confined
  to the near-surface region have little effect on the low-frequency p
  modes: this is as one would expect from a simple asymptotic description
  which shows that these modes have upper turning points located well
  beneath the photosphere. However, some examples of structural changes
  show that, if the changes are viewed at fixed fractional radius (an
  Eulerian description), the small frequency shifts at low frequency
  come about through near-cancellation of different contributions which
  are individually much larger than the resultant shifts themselves;
  the reason is that even so-called near-surface changes extend
  substantially below the upper turning points of these modes. We
  demonstrate that the corresponding changes at fixed fractional mass
  (a Lagrangian description) are confined much closer to the surface,
  so that the small frequency shifts come about in a natural way.

Title: The seismic structure of the Sun from GONG
Authors: Anderson, E.; Antia, H. M.; Basu, S.; Chaboyer, B.; Chitre,
   S. M.; Christensen-Dalsgaard, J.; Eff-Darwich, A.; Elliott, J. R.;
   Giles, P. M.; Gough, D. O.; Guzik, J. A.; Harvey, J. W.; Hill,
   F.; Leibacher, J. W.; Kosovichev, A. G.; Monteiro, M. J. P. F. G.;
   Richard, O.; Sekii, T.; Shibahashi, H.; Takata, M.; Thompson, M. J.;
   Toomre, J.; Vauclair, S.; Vorontsov, S. V.
Bibcode: 1997IAUS..181..151A
Altcode:
  No abstract at ADS

Title: On the use of the error correlation function in helioseismic
    inversions
Authors: Howe, R.; Thompson, M. J.
Bibcode: 1996MNRAS.281.1385H
Altcode:
  A diagnostic of helioseismic inversions that has not so far been
  greatly used is the correlation function describing how the errors
  in the solutions at different points in the solar interior are
  correlated. Even if the errors in the input data are uncorrelated,
  the solution errors will in general be correlated. We investigate the
  correlation functions for a variety of inversion methods commonly
  used in helioseismology, using the estimation of a one-dimensional
  rotation profile as a prototypical example. As we demonstrate, there
  are characteristic length scales over which the errors are correlated,
  which are similar among different inversion methods. However, there
  can also be dramatic differences in the error correlations among
  otherwise similar looking inversions if the parameters are chosen
  inappropriately. It is therefore advisable to consider the correlation
  function, as well as other diagnostics, when assessing the reliability
  of an inversion solution.

Title: Solar structure as revealed by 1 year LOWL data
Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Schou, J.; Thompson,
   M. J.; Tomczyk, S.
Bibcode: 1996BASI...24..147B
Altcode:
  No abstract at ADS

Title: Results from the LOWL instrument
Authors: Schou, J.; Tomczyk, S.; Thompson, M. J.
Bibcode: 1996BASI...24..375S
Altcode:
  No abstract at ADS

Title: Low-degree frequency splitting measurements and the rotation
    rate of the solar core
Authors: Tomczyk, S.; Schou, J.; Thompson, M. J.
Bibcode: 1996BASI...24..245T
Altcode:
  No abstract at ADS

Title: The Current State of Solar Modeling
Authors: Christensen-Dalsgaard, J.; Dappen, W.; Ajukov, S. V.;
   Anderson, E. R.; Antia, H. M.; Basu, S.; Baturin, V. A.; Berthomieu,
   G.; Chaboyer, B.; Chitre, S. M.; Cox, A. N.; Demarque, P.; Donatowicz,
   J.; Dziembowski, W. A.; Gabriel, M.; Gough, D. O.; Guenther, D. B.;
   Guzik, J. A.; Harvey, J. W.; Hill, F.; Houdek, G.; Iglesias, C. A.;
   Kosovichev, A. G.; Leibacher, J. W.; Morel, P.; Proffitt, C. R.;
   Provost, J.; Reiter, J.; Rhodes, E. J., Jr.; Rogers, F. J.; Roxburgh,
   I. W.; Thompson, M. J.; Ulrich, R. K.
Bibcode: 1996Sci...272.1286C
Altcode:
  Data from the Global Oscillation Network Group (GONG) project and
  other helioseismic experiments provide a test for models of stellar
  interiors and for the thermodynamic and radiative properties, on which
  the models depend, of matter under the extreme conditions found in the
  sun. Current models are in agreement with the helioseismic inferences,
  which suggests, for example, that the disagreement between the predicted
  and observed fluxes of neutrinos from the sun is not caused by errors in
  the models. However, the GONG data reveal subtle errors in the models,
  such as an excess in sound speed just beneath the convection zone. These
  discrepancies indicate effects that have so far not been correctly
  accounted for; for example, it is plausible that the sound-speed
  differences reflect weak mixing in stellar interiors, of potential
  importance to the overall evolution of stars and ultimately to estimates
  of the age of the galaxy based on stellar evolution calculations.

Title: Filtering out near-surface uncertainties from helioseismic
    inversions
Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Perez Hernandez,
   F.; Thompson, M. J.
Bibcode: 1996MNRAS.280..651B
Altcode:
  The differences between observed solar p-mode frequencies and the
  frequencies of a reference model can be inverted to infer the structure
  of the Sun using a variety of linear inversion techniques. However, it
  is well known that the adiabatic description, which is often employed
  in frequency calculations, breaks down in the outermost layers of the
  Sun. This and other uncertainties in the treatment of the superficial
  layers introduce a slowly varying frequency-dependent function
  into the frequency differences. <P />We present here a technique to
  pre-process the frequency differences prior to applying any of the
  standard inversion techniques in order to eliminate the frequency
  dependent component which arises from the near-surface uncertainties,
  suppressing also the corresponding contributions from the kernels
  relating frequency differences to differences in structure. This
  is achieved by applying suitable linear filters to the frequency
  differences and to the mode kernels. We obtain the filtered kernels
  and demonstrate that the surface contribution can be successfully
  suppressed. We also present the results of the inversions performed
  after the data and mode kernels have been filtered.

Title: The Seismic Structure of the Sun
Authors: Gough, D. O.; Kosovichev, A. G.; Toomre, J.; Anderson,
   E.; Antia, H. M.; Basu, S.; Chaboyer, B.; Chitre, S. M.;
   Christensen-Dalsgaard, J.; Dziembowski, W. A.; Eff-Darwich, A.;
   Elliott, J. R.; Giles, P. M.; Goode, P. R.; Guzik, J. A.; Harvey,
   J. W.; Hill, F.; Leibacher, J. W.; Monteiro, M. J. P. F. G.; Richard,
   O.; Sekii, T.; Shibahashi, H.; Takata, M.; Thompson, M. J.; Vauclair,
   S.; Vorontsov, S. V.
Bibcode: 1996Sci...272.1296G
Altcode:
  Global Oscillation Network Group data reveal that the internal
  structure of the sun can be well represented by a calibrated standard
  model. However, immediately beneath the convection zone and at the
  edge of the energy-generating core, the sound-speed variation is
  somewhat smoother in the sun than it is in the model. This could be a
  consequence of chemical inhomogeneity that is too severe in the model,
  perhaps owing to inaccurate modeling of gravitational settling or to
  neglected macroscopic motion that may be present in the sun. Accurate
  knowledge of the sun's structure enables inferences to be made about
  the physics that controls the sun; for example, through the opacity,
  the equation of state, or wave motion. Those inferences can then be
  used elsewhere in astrophysics.

Title: Measurement of the Rotation Rate in the Deep Solar Interior
Authors: Tomczyk, S.; Schou, J.; Thompson, M. J.
Bibcode: 1996AAS...188.6903T
Altcode: 1996BAAS...28..935T
  We present a measurement of the rotation rate in the interior of the
  Sun based on two years of observations with the LOWL instrument. LOWL
  allows the observation of solar oscillations with degrees from 0
  to 100, thus providing a homogeneous low- and intermediate-degree
  dataset. Significantly, it is able to make spatially resolved
  observations of low degree modes, thereby making it possible to separate
  the different modes within a given multiplet. This reduces the potential
  for systematic errors compared to observations using integrated
  sunlight. We have used observations of the frequency splittings
  of modes with degrees from 1 to 100 to infer the rotation rate in
  the solar interior with some radial resolution and without excessive
  errors. Over most of the interior we have also been able to estimate
  the latitudinal variation of the rotation rate. We confirm earlier
  findings that near the base of the convection zone the solar rotation
  profile undergoes a transition from surface-like differential rotation
  to a rotation rate that is independent of latitude. Additionally,
  we find that below the base of the convection zone our measurement is
  consistent with rigid body rotation at a rate somewhat lower than the
  surface equatorial rate. This measurement provides strong constraints
  on the theories of angular momentum transport in solar-type stars.

Title: Differential Rotation and Dynamics of the Solar Interior
Authors: Thompson, M. J.; Toomre, J.; Anderson, E. R.; Antia, H. M.;
   Berthomieu, G.; Burtonclay, D.; Chitre, S. M.; Christensen-Dalsgaard,
   J.; Corbard, T.; De Rosa, M.; Genovese, C. R.; Gough, D. O.; Haber,
   D. A.; Harvey, J. W.; Hill, F.; Howe, R.; Korzennik, S. G.; Kosovichev,
   A. G.; Leibacher, J. W.; Pijpers, F. P.; Provost, J.; Rhodes, E. J.,
   Jr.; Schou, J.; Sekii, T.; Stark, P. B.; Wilson, P. R.
Bibcode: 1996Sci...272.1300T
Altcode:
  Splitting of the sun's global oscillation frequencies by large-scale
  flows can be used to investigate how rotation varies with radius
  and latitude within the solar interior. The nearly uninterrupted
  observations by the Global Oscillation Network Group (GONG) yield
  oscillation power spectra with high duty cycles and high signal-to-noise
  ratios. Frequency splittings derived from GONG observations confirm
  that the variation of rotation rate with latitude seen at the surface
  carries through much of the convection zone, at the base of which is
  an adjustment layer leading to latitudinally independent rotation at
  greater depths. A distinctive shear layer just below the surface is
  discernible at low to mid-latitudes.

Title: Solar Internal Rotation and Dynamics from GONG Frequency
    Splittings
Authors: Thompson, M. J.; Toomre, J.; GONG Dynamics Inversion Team
Bibcode: 1996AAS...188.5305T
Altcode: 1996BAAS...28..903T
  The splitting of the Sun's global mode frequencies by large-scale flows
  can be used to investigate the rotation profile in both radius and
  latitude within the convection zone and deeper radiative interior. The
  inversion of GONG data confirms that the surface latitudinal variation
  of the rotation rate carries through much of the convection zone. At the
  base of the convection zone there is a currently unresolved adjustment
  layer with latitudinally independent rotation at greater depths. A
  shearing layer just below the surface is discernable at low to mid
  latitudes. Such global investigations are supplemented by local area
  analyses via ring diagrams, which enable us to probe the subsurface
  variation of rotation with depth beneath selected regions of the Sun.

Title: The Solar Acoustic Spectrum and Eigenmode Parameters
Authors: Hill, F.; Stark, P. B.; Stebbins, R. T.; Anderson, E. R.;
   Antia, H. M.; Brown, T. M.; Duvall, T. L., Jr.; Haber, D. A.;
   Harvey, J. W.; Hathaway, D. H.; Howe, R.; Hubbard, R. P.; Jones,
   H. P.; Kennedy, J. R.; Korzennik, S. G.; Kosovichev, A. G.; Leibacher,
   J. W.; Libbrecht, K. G.; Pintar, J. A.; Rhodes, E. J., Jr.; Schou, J.;
   Thompson, M. J.; Tomczyk, S.; Toner, C. G.; Toussaint, R.; Williams,
   W. E.
Bibcode: 1996Sci...272.1292H
Altcode:
  The Global Oscillation Network Group (GONG) project estimates
  the frequencies, amplitudes, and linewidths of more than 250,000
  acoustic resonances of the sun from data sets lasting 36 days. The
  frequency resolution of a single data set is 0.321 microhertz. For
  frequencies averaged over the azimuthal order m, the median formal
  error is 0.044 microhertz, and the associated median fractional error
  is 1.6 x 10<SUP>-5</SUP>. For a 3-year data set, the fractional error
  is expected to be 3 x 10<SUP>-6</SUP>. The GONG m-averaged frequency
  measurements differ from other helioseismic data sets by 0.03 to 0.08
  microhertz. The differences arise from a combination of systematic
  errors, random errors, and possible changes in solar structure.

Title: The Sun's Hydrostatic Structure from LOWL Data
Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Schou, J.; Thompson,
   M. J.; Tomczyk, S.
Bibcode: 1996ApJ...460.1064B
Altcode:
  Recent observations with the LOWL (Low-Degree [l] Oscillations
  Experiment) instrument have for the first time provided a uniform set of
  frequencies that allow detailed inversion for the structure of much of
  the Sun's deep interior. We present the results of inverting the LOWL
  data and compare them with the corresponding results obtained using
  inhomogeneous data sets from more than one instrument. Furthermore,
  improvements in the description of the required physics motivates the
  calculation of new solar models. Thus, we present results of inversions
  of the LOWL data against several reference models using up-to-date
  physics. In models including the gravitational settling of helium, the
  sound speed and density agree with the Sun to within substantially
  better than 1%. We test various modifications to the physics of
  the models in order to see if the remaining small (but significant)
  discrepancy between the Sun and the models can be removed. We find
  that none of the modifications tested can adequately account for the
  remaining discrepancy, though a small increase in helium diffusion
  in the core gives a modest improvement over the standard diffusion
  model. Finally, we find that the seismic data support theoretical
  calculations that indicate that settling of heavier elements has
  reduced the present surface value of Z by about 8% relative to its
  mean interior value.

Title: The Sun's rotation rate in its equatorial plane.
Authors: Antia, H. M.; Chitre, S. M.; Thompson, M. J.
Bibcode: 1996A&A...308..656A
Altcode:
  We investigate the Sun's rotation rate in its equatorial plane, as
  a function of depth, using Big Bear data for the years 1986, 1988,
  1989 and 1990. One novel feature of this investigation is that we
  have used an iterative inversion technique, based upon the regularized
  least-squares method. Such methods generally have one or more adjustable
  parameters, and the details of the inferred rotation profile depend
  upon the values chosen for those parameters. We find that the iterative
  technique produces results that are much less sensitive to the values of
  the parameters, which may be seen as one advantage of our procedure. Our
  results exhibit various features, including a secular decrease in the
  rotation rate beneath the convection zone, a locally enhanced rotation
  rate near 0.9R<SUB>sun</SUB>_ (R<SUB>sun</SUB>_ being the photospheric
  radius), and a local minimum near 0.6R<SUB>sun</SUB>_. Not only are
  these features apparently fairly robust from year to year, they have
  all variously been seen in inversions of other datasets. However,
  we demonstrate that some caution should be exercised in interpreting
  such features in the Sun's equatorial rotation rate.

Title: Seismic properties of the Sun's superadiabatic
    layer. I. Theoretical modelling and parametrization of the
    uncertainties.
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1996A&A...307..624M
Altcode:
  Some alternatives to the traditional mixing-length theory (MLT)
  have recently been proposed for modelling convective heat transport
  inside stars. The ideal formulation is one that does not involve
  any free parameters. However, in our present state of ignorance we
  still need at least one free parameter in order to build solar models
  with the correct radius. Having adjusted this parameter (e.g. the
  mixing-length parameter α_c_) to obtain the observed radius, we cannot
  discriminate non-seismically between different convective theories,
  regardless of how low-efficiency convection is treated. In this paper
  we consider how the additional information provided by global p-mode
  frequencies can be used to investigate low-efficiency convection at
  the top of the solar convective envelope and discriminate between
  different theories. We consider a parametrization which in addition
  to the mixing length has two further parameters: one (β_c_) which
  regulates the relative degree of overadiabaticity (or inefficiency) of
  convection, and a second (m) that affects the transition between the
  regimes of efficient and inefficient convection. Our parametrization
  includes traditional MLT__ and the theory of Canuto &amp; Mazzitelli
  as particular cases. We study the effect of varying these parameters
  by constructing a series of envelope models with the same depth of
  the convection zone and computing their oscillation frequencies. We
  discuss our results in terms of kernels relating frequency changes to
  changes in the structure of the superadiabatic region.

Title: A modified R^1∘xR^1 method for helioseismic rotation
    inversions
Authors: Pijpers, F. P.; Thompson, M. J.
Bibcode: 1996MNRAS.279..498P
Altcode: 1995astro.ph.10143P
  We present an efficient method for two-dimensional (2D) inversions
  for the solar rotation rate using the Subtractive Optimally Localized
  Averages (SOLA) method and a modification of the R^1∘xR^1 technique
  proposed by Sekii. The SOLA method is based on explicit construction of
  averaging kernels similar to the Backus-Gilbert method. The versatility
  and reliability of the SOLA method in reproducing a target form for
  the averaging kernel, in combination with the idea of the R^1∘xR^1
  decomposition, results in a computationally very efficient inversion
  algorithm. This is particularly important for full 2D inversions of
  helioseismic data in which the number of modes runs into at least tens
  of thousands.

Title: On constructing seismic models of the Sun.
Authors: Basu, S.; Thompson, M. J.
Bibcode: 1996A&A...305..631B
Altcode:
  Observed p-mode frequencies have been extensively used to determine
  the the Sun's radial structure. The results of such inversions are
  often called "seismic models" of the Sun. In this work we investigate
  whether one can in fact construct models that match the measured solar
  frequencies to within observational errors. We invert linearized
  equations, relating frequency differences between the Sun and a
  reference model to differences in their structure, using a Regularized
  Least Squares (RLS) technique with second derivative smoothing. As a
  test, we first invert frequencies from test models. Random noise is
  added to these to simulate the observers' quoted errors for solar
  data. We investigate how the goodness of fit to the data, and the
  acceptability of the solution, depend upon the number of spline
  knots in the solution functions and upon the amount of smoothing
  used. With this artificial data, we can obtain a chi-squared per
  degree of freedom (χ<SUB>nu</SUB>_^2^) of order unity even when the
  differences between the reference and test models are quite large. In
  contrast, using the most widely used compilation of observed solar
  frequencies, we are unable to get the value of χ<SUB>nu</SUB>_^2^
  close to one. Replacing the low degree data with recent data from the
  BISON network, and omitting frequencies determined by the ridge-fitting
  method (which could be more susceptible to systematic error), the value
  χ<SUB>nu</SUB>_^2^ can be reduced substantially. We discuss possible
  causes for the small remaining excess in χ<SUB>nu</SUB>_^2^.

Title: Filtering in Inversion for Solar Internal Structure
Authors: Basu, Sarbani; Christensen-Dalsgaard, J.; Pérez Hernández,
   F.; Thompson, M. J.
Bibcode: 1996imie.conf...32B
Altcode:
  No abstract at ADS

Title: Averaging Kernels, Error Correlation Functions and Linear
    Methods in Helioseismology
Authors: Howe, Rachel; Thompson, Michael J.
Bibcode: 1996imie.conf...40H
Altcode:
  No abstract at ADS

Title: Results From the LOWL Instrument
Authors: Schou, J.; Tomczyk, S.; Thompson, M. J.
Bibcode: 1995AAS...18710101S
Altcode: 1995BAAS...27.1426S
  In this poster we will present various results from one year of
  observations with the LOWL instrument. The LOWL instrument is designed
  to observe oscillations with degrees l from 0 to about 100 providing a
  homogeneous dataset for inversions. Given the spatial resolution of the
  instrument it is possible to separate different azimuthal orders m even
  for the lowest degree modes, hopefully giving more accurate splittings
  than those determined using integrated sunlight for a similar time
  period. We will show the results of an inversion for the solar rotation
  rate between 0.1R_sun and 0.95R_sun. Given the long duration and the
  large number of terms used to describe the m-dependence of the mode
  frequencies we have been able to obtain very good resolution in both
  the radial direction and in latitude while keeping the statistical
  errors low, thereby obtaining more accurate results than previously
  possible. We will also present results of analyzing different parts of
  the time-series and compare the temporal variations in mode frequencies
  and splittings with variations in the solar activity.

Title: Helioseismic estimation of convective overshoot in the Sun
Authors: Christensen-Dalsgaard, Jorgen; Monteiro, Mario J. P. F. G.;
   Thompson, Michael J.
Bibcode: 1995MNRAS.276..283C
Altcode:
  By using the periodic signal present in the frequencies of
  oscillation due to the base of the solar convection zone, Monteiro,
  Christensen-Dalsgaard &amp; Thompson gave an upper limit to the
  extent of a layer of convective overshooting in the Sun. Alternative
  studies have suggested that it may not be possible to do so since the
  amplitude of the signal does not vary monotonically with the extent
  of the layer. <P />In this work a new more complete set of models is
  used to compare the values of the amplitude obtained from the fitting
  of the signal with the expected amplitudes. These are determined using
  the assumption that the rapid variation occurring at the base of the
  convection zone and creating the periodic signal can be described as
  discontinuities of the sound-speed derivatives. The amplitude of the
  signal due to the discontinuity of the third derivative of the sound
  speed is then proportional to the derivative of the radiative gradient,
  while the amplitude resulting from the discontinuity of the second
  derivative is proportional to the difference between radiative and
  adiabatic gradients at the position where the transition occurs. The
  latter is non-zero only if overshoot is present. <P />Asymptotic
  predictions of the amplitudes of the signal in the p-mode frequencies
  are in good agreement with the values found from fitting models with
  substantial overshoot regions; as was also found by Monteiro et al.,
  the observed solar frequencies place severe limits on the extent of
  overshoot of this nature.

Title: Linear inversions for the Sun's internal rotation
Authors: Thompson, M. J.
Bibcode: 1995InvPr..11..709T
Altcode:
  No abstract at ADS

Title: Measurement of the Rotation Rate in the Deep Solar Interior
Authors: Tomczyk, S.; Schou, J.; Thompson, M. J.
Bibcode: 1995ApJ...448L..57T
Altcode:
  We present a measurement of solar internal rotation based
  on observations obtained over 3 months in early 1994 with a new
  instrument called LOWL. This instrument allows for the simultaneous
  observation of low- and intermediate-degree solar oscillations with
  spatial resolution. We have measured the frequency splitting of 673
  multiplets with degrees ranging from 1 to 80 and inverted these to
  derive an estimate of the solar internal rotation profile between 0.2
  and 0.85 R⊙. The accuracy of this measurement ranges from ~1% in the
  outer regions to ~5% at 0.2 R⊙ and thus places better constraints than
  hitherto on the rotation in the deep solar interior. We confirm earlier
  findings that near the base of the convection zone the solar rotation
  profile undergoes a transition from surface-like differential rotation
  to a rotation rate that is independent of latitude. In addition, we
  find that from the base of the convection zone down to 0.2 R⊙ our
  measurement is consistent with rigid body rotation at a rate somewhat
  lower than the surface equatorial rate. The accuracy of our measurement
  in the deep solar interior provides a strong constraint to theories
  of solar and stellar angular momentum transport.

Title: A Measurement of the Rotation Rate in the Deep Solar Interior
Authors: Schou, J.; Tomczyk, S.; Thompson, M. J.
Bibcode: 1995ESASP.376b.275S
Altcode: 1995soho....2..275S; 1995help.confP.275S
  No abstract at ADS

Title: The Sensitivity of Various Mode Sets for Probing Differential
    Rotation Shear Zones
Authors: Christensen-Dalsgaard, J.; Schou, J.; Thompson, M. J.;
   Toomre, J.
Bibcode: 1995ESASP.376b..41C
Altcode: 1995soho....2...41C; 1995help.confP..41C
  The potential of forthcoming datasets from GONG and SOI for resolving
  long-lived azimuthal jets and shearing flows is investigated. The
  authors construct various artificial datasets, containing noise
  resembling that for a one-year observing run. These are then inverted,
  using a 2-D regularized least squares (RLS) inversion. In particular,
  the authors investigate the ability of the RLS method to form
  well-localized averages of the rotation rate, as measured by the
  averaging kernels, using an extensive mode set as well as subsets
  thereof. The authors show that it is possible to keep the noise in
  the solution down to a few nanohertz in much of the solar interior,
  while obtaining very reasonable resolution, for a GONG-like dataset.

Title: Solar Structure Inversion with LOWL Data
Authors: Basu, S.; Christensen-Dalsgaard, J.; Schou, J.; Thompson,
   M. J.; Tomczyk, S.
Bibcode: 1995ESASP.376b..25B
Altcode: 1995help.confP..25B; 1995soho....2...25B
  Presents inversion results for the radial hydrostatic structure of
  the Sun, using six months of oscillation data obtained with the LOWL
  instrument. Using modes with degrees from 0 to 90 and frequencies
  between 1.5 and 3.5 mHz, the authors have inferred the variation with
  depth of the sound speed, density ρ and u = p/ρ (p being pressure)
  from r = 0.05 R<SUB>sun</SUB> to 0.85 R<SUB>sun</SUB>. They find that
  in this region the sound speed in the Sun is within 0.15% of that of a
  model constructed using the MHD equation of state and OPAL opacities
  and incorporating helium diffusion. The density difference between
  Sun and model is less than 0.8%. Given the small error bars on the
  inversion results these small differences are significant, however. The
  solar sound speed appears to be higher than in the model for r &lt;
  0.2 R<SUB>sun</SUB> . The authors speculate that this might indicate
  interesting physics in the inner core.

Title: Constraining Solar Core Rotation with Genetic Forward Modelling
Authors: Tomczyk, S.; Charbonneau, P.; Schou, J.; Thompson, M. J.
Bibcode: 1995ESASP.376b.271T
Altcode: 1995soho....2..271T; 1995help.confP.271T
  No abstract at ADS

Title: Uncertainties for Two-dimensional Models of Solar Rotation
    from Helioseismic Eigenfrequency Splitting
Authors: Genovese, Christopher R.; Stark, Philip B.; Thompson,
   Michael J.
Bibcode: 1995ApJ...443..843G
Altcode:
  Observed solar p-mode frequency splittings can be used to estimate
  angular velocity as a function of position in the solar interior. Formal
  uncertainties of such estimates depend on the method of estimation
  (e.g., least-squares), the distribution of errors in the observations,
  and the parameterization imposed on the angular velocity. We obtain
  lower bounds on the uncertainties that do not depend on the method
  of estimation; the bounds depend on an assumed parameterization, but
  the fact that they are lower bounds for the 'true' uncertainty does
  not. Ninety-five percent confidence intervals for estimates of the
  angular velocity from 1986 Big Bear Solar Observatory (BBSO) data, based
  on a 3659 element tensor-product cubic-spline parameterization, are
  everywhere wider than 120 nHz, and exceed 60,000 nHz near the core. When
  compared with estimates of the solar rotation, these bounds reveal that
  useful inferences based on pointwise estimates of the angular velocity
  using 1986 BBSO splitting data are not feasible over most of the Sun's
  volume. The discouraging size of the uncertainties is due principally
  to the fact that helioseismic measurements are insensitive to changes in
  the angular velocity at individual points, so estimates of point values
  based on splittings are extremely uncertain. Functionals that measure
  distributed 'smooth' properties are, in general, better constrained than
  estimates of the rotation at a point. For example, the uncertainties
  in estimated differences of average rotation between adjacent blocks
  of about 0.001 solar volumes across the base of the convective zone
  are much smaller, and one of several estimated differences we compute
  appears significant at the 95% level.

Title: Results from the LOWL Instrument
Authors: Schou, J.; Tomczyk, S.; Thompson, M. J.
Bibcode: 1995SPD....26..402S
Altcode: 1995BAAS...27..954S
  No abstract at ADS

Title: Optimally Localized Kernels for 2D Helioseismic Inversion
Authors: Christensen-Dalsgaard, J.; Larsen, R. M.; Schou, J.; Thompson,
   M. J.
Bibcode: 1995ASPC...76...70C
Altcode: 1995gong.conf...70C
  No abstract at ADS

Title: SOLA Inversions for the Radial Structure of the Sun
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1995ASPC...76..144C
Altcode: 1995gong.conf..144C
  No abstract at ADS

Title: Some Aspects of Helioseismic Time-Series Analysis
Authors: Schou, J.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1995ASPC...76..528S
Altcode: 1995gong.conf..528S
  No abstract at ADS

Title: A Self-Consistent Approach to Filtering Out Near-Surface
    Uncertainties from Helioseismic Inversions
Authors: Basu, S.; Thompson, M. J.; Christensen-Dalsgaard, J.; Perez
   Hernandez, F.
Bibcode: 1995ASPC...76..152B
Altcode: 1995gong.conf..152B
  No abstract at ADS

Title: Helioseismic Constraints on Theories of Convection
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1995ASPC...76..128M
Altcode: 1995gong.conf..128M
  No abstract at ADS

Title: On Constructing Seismic Models of the Sun's Radial Structure
Authors: Basu, S.; Thompson, M. J.
Bibcode: 1995ASPC...76..148B
Altcode: 1995gong.conf..148B
  No abstract at ADS

Title: Hunting for Azimuthal Jets and Shearing Flows in the Solar
    Convection Zone
Authors: Christensen-Dalsgaard, J.; Schou, J.; Thompson, M. J.;
   Toomre, J.
Bibcode: 1995ASPC...76..212C
Altcode: 1995gong.conf..212C
  No abstract at ADS

Title: A Measurement of the Rotation Rate in the Deep Solar Interior
Authors: Schou, J.; Tomczyk, S.; Thompson, M. J.
Bibcode: 1994AAS...185.4401S
Altcode: 1994BAAS...26Q1377S
  Measurements of the rotation rate in the deep solar interior using
  helioseismology have given inconsistent results, presumably due to
  problems with the algorithms used for the analysis of spatially
  unresolved observations of the oscillations. Here we present a
  measurement of the rotation rate in the interior of the Sun based
  on observations with a new instrument called LOWL. Unlike earlier
  instruments this instrument allows the observation of oscillations
  with degrees from 0 to ~ 80. In particular it is able to make spatially
  resolved observations of low degree modes, thereby making it possible to
  spatially separate the different modes within a given multiplet. This
  reduces the potential for systematic errors compared to observations
  using integrated sunlight. We have used observations of the frequency
  splittings of modes with degrees from 1 to 80 to infer the rotation rate
  in the solar interior down to ~ 0.2 R_⊙ with some radial resolution
  and without excessive errors. Over part of the range we have also been
  able to estimate the latitudinal variation of the rotation rate. This
  measurement provides strong constraints on the theories of solar and
  stellar angular momentum transport.

Title: On Comparing Helioseismic Two-dimensional Inversion Methods
Authors: Schou, J.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1994ApJ...433..389S
Altcode:
  We consider inversion techniques for investigating the structure and
  dynamics of the solar interior as functions of radius and latitude. In
  particular, we look at the problem of inferring the radial and
  latitudinal dependence of the Sun's internal rotation, using a fully
  two-dimensional least-squares inversion algorithm. Concepts such as
  averaging kernels, measures of resolution, and trade-off curves, which
  have previously been used in the one-dimensional case, are generalized
  to facilitate a comparison of two-dimensional methods. We investigate
  the weighting given to different modes and discuss the implications of
  this for observational strategies. As an illustration we use a mode
  set whose properties are similar to those expected for data from the
  GONG network.

Title: Conceptual Astronomy
Authors: Thompson, M. J.
Bibcode: 1994ConPh..35..289T
Altcode:
  No abstract at ADS

Title: Seismic study of overshoot at the base of the solar convective
    envelope
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1994A&A...283..247M
Altcode:
  Sharp transitions in the internal stratification of a star give rise to
  a characteristic signature in normal-mode frequencies. In particular,
  if in the Sun such a feature were located well inside the acoustic
  cavity of many solar p modes, it would give rise to a signal that was a
  periodic function of the frequency of the modes. We use this signature
  to detect the base of the solar convection zone and to investigate the
  existence of convective overshoot into the radiative interior. Two
  methods are considered. The 'absolute' method obtains the residuals
  in the frequencies after making a smooth fit in mode order n, and
  then uses an asymptotic description of the eigenfunctions to make a
  fit to the residuals. The 'differential' method makes an asymptotic
  fit to the differences between solar frequencies and the frequencies
  of a theoretical model. Various theoretical models of overshoot at
  the base of the convection zone predict the existence of a rather
  abrupt transition to subadiabatic stratification at the base of the
  overshoot region. We find no strong evidence for the existence of an
  overshoot region of this kind. Indeed if the overshoot consists of an
  essentially adiabatic extension of the convection zone followed by an
  abrupt transition to radiative stratification then we may (at the 95%
  confidence level) put an upper limit of 0.07 local pressure scale
  heights on the extent of the overshoot layer.

Title: Recent results from helioseismology.
Authors: Thompson, M. J.
Bibcode: 1994LNP...432...19T
Altcode: 1994LNPM...11...19T
  The very accurately measured frequencies of the Sun's global oscillation
  are providing us with a detailed picture of the solar interior. The
  adiabatic sound speed is of foremost importance in determining
  the observed p-mode frequencies and hence is readily accessible to
  seismic analysis of the frequency data. It has thus been known for
  some time that the sound speed in the bulk of the radiative interior
  is greater than in theoretical models. Much of this discrepancy is
  removed by the latest Livermore opacities, but a significant discrepancy
  remains. The cause of this discrepancy may be settling and diffusion of
  helium in the solar interior. This would also explain the discrepancy
  between seismic measurements of the envelope helium abundance and the
  abundance required to produce correctly calibrated evolution models. The
  frequencies also enable to pinpoint the base of the convection zone and
  to investigate the extent of overshoot into the underlying convectively
  stable region. The variation of the p-mode frequencies with time is
  discussed, as are the current helioseismic determinations of the Sun's
  internal rotation. Finally future prospects are considered.

Title: The SOLA method for helioseismic inversion
Authors: Pijpers, F. P.; Thompson, M. J.
Bibcode: 1994A&A...281..231P
Altcode:
  The Subtractive Optimally Localized Averages (SOLA) method is a
  versatile and efficient technique for inverting helioseismic data. The
  SOLA method is based on explicit construction of Backus-Gilbert
  averaging kernels, but whereas the more usual formulations of the
  optimally localized averages (OLA) method use a multiplicative penalty
  function to localize the kernels, the distinctive idea of SOLA is that
  one specifies a desired target form for the kernels and then minimizes
  the integrated squared difference between the kernels and the target
  form. This allows great versatility in the choice of target form, and
  furthermore SOLA has the significant advantage of being computationally
  more efficient than the usual OLA formulations. A Gaussian target
  function is a useful choice, and we use the example of determining
  the Sun's internal rotation to explore how the parameter values (such
  as the Gaussian's width) should best be chosen. Some alternatives to
  using a Gaussian function as target function are discussed and applied
  to artificial data in a blind experiment. In particular we show that it
  is possible to invert directly for the gradient of the rotation. This
  may be of interest if there are localized large gradients in the
  rotation rate.

Title: The Depth of the Solar Convection Zone
Authors: Christensen-Dalsgaard, J.; Gough, D. O.; Thompson, M. J.
Bibcode: 1994snft.book..427C
Altcode:
  No abstract at ADS

Title: Generalized Singular Value Decomposition Analysis of
    Helioseismic Inversions
Authors: Christensen-Dalsgaard, J.; Hansen, P. C.; Thompson, M. J.
Bibcode: 1993MNRAS.264..541C
Altcode:
  We present the generalized singular value decomposition (GSVD) as a
  powerful tool for the analysis of 111-conditioned inversion problems,
  such as arise in helioseismology and other areas of astronomy. The
  GSVD provides rather natural bases with which to express the
  various properties of the inversion, in particular the solution,
  the inversion coefficients (which relate the solution to the data)
  and the averaging kernels (which relate the solution to the underlying
  unknown function). These facilitate an analysis of resolution and error
  properties. We apply the theory to a helioseismic example and find inter
  alia that, for our prototypical problem, there is an effective limit to
  the information content of the mode set in the presence of reasonable
  data errors which is much less than might have been expected from the
  number of modes. We show that various popular inversion methods can be
  analysed using the tools developed here. We find in our helioseismic
  application that the methods make very similar use of the data.

Title: Resonant Alfvén wave excitation in two-dimensional systems:
    Singularities in partial differential equations
Authors: Thompson, Michael J.; Wright, Andrew N.
Bibcode: 1993JGR....9815541T
Altcode:
  The resonant excitation of Alfvén waves is considered in a cold plasma
  embedded in a uniform magnetic field Bẑ. All wave fields are assumed
  to vary as exp[i(λy-ωt)], and the background medium is invariant in
  y. The background density distribution ρ<SUB>0</SUB>(x,z) is otherwise
  completely arbitrary. Regular and singular solutions for the waves are
  derived systematically in the vicinity of a resonance by considering a
  generalized Frobenius series, and we are able to recover many results
  found in earlier studies. Some new features of our work include a
  generalization of the overlap integral determining the efficiency
  with which any resonance may be excited, and the possibility that
  ξ<SUB>y</SUB>~1/x<SUP>N</SUP> (N=1,2,3...) at the resonance. Hitherto
  only the solution with N=1 has been considered.

Title: A preprocessing strategy for helioseismic inversions
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1993A&A...272L...1C
Altcode:
  Helioseismic inversion in general involves considerable
  computational expense, due to the large number of modes that is
  typically considered. This is true in particular of the widely used
  optimally localized averages (OLA) inversion methods, which require
  the inversion of one or more matrices whose order is the number of
  modes in the set. However, the number of practically independent
  pieces of information that a large helioseismic mode set contains
  is very much less than the number of modes, suggesting that the set
  might first be reduced before the expensive inversion is performed. We
  demonstrate with a model problem that by first performing a singular
  value decomposition the original problem may be transformed into a
  much smaller one, reducing considerably the cost of the OLA inversion
  and with no significant loss of information.

Title: Effects of Diffusion on Solar Models and Their Oscillation
    Frequencies
Authors: Christensen-Dalsgaard, J.; Proffitt, C. R.; Thompson, M. J.
Bibcode: 1993ApJ...403L..75C
Altcode:
  Settling and diffusion of helium have significant effects on the
  structure of solar models and their oscillation frequencies. We examine
  these effects in considerably more detail than has been done before,
  and we compare the computed frequencies with an extensive set of
  observed frequencies. We find that inclusion of diffusion results
  in a significant improvement in the agreement between theory and
  observations.

Title: On Detecting Overshoot Below the Sun's Convective Envelope
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1993ASPC...42..253M
Altcode: 1993gong.conf..253M
  No abstract at ADS

Title: Two-dimensional helioseismic inversions
Authors: Schou, J.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1993ASPC...40...72S
Altcode: 1993IAUCo.137...72S; 1993ist..proc...72S
  No abstract at ADS

Title: Detecting convective overshoot in solar-type stars
Authors: Monteiro, M. J. P. F. G.; Christensen-Dalsgaard, J.; Thompson,
   M. J.
Bibcode: 1993ASPC...40..557M
Altcode: 1993IAUCo.137..557M; 1993ist..proc..557M
  No abstract at ADS

Title: Faster Formulations of the Ola Method
Authors: Pijpers, F. P.; Thompson, M. J.
Bibcode: 1993ASPC...42..245P
Altcode: 1993gong.conf..245P
  No abstract at ADS

Title: Tests and Applications of the SOLA Inversion Method - a New
    Determination of the Solar Rotation Rate
Authors: Pijpers, F. P.; Thompson, M. J.
Bibcode: 1993ASPC...42..241P
Altcode: 1993gong.conf..241P
  No abstract at ADS

Title: Two-Dimensional Helioseismic Inversions
Authors: Schou, J.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1993ASPC...42..205S
Altcode: 1993gong.conf..205S
  No abstract at ADS

Title: A Hands-On IDL Program for Helioseismic Inversion
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1993ASPC...42..249C
Altcode: 1993gong.conf..249C
  No abstract at ADS

Title: Seismic Investigation of the Sun's Internal Structure and
    Rotation
Authors: Thompson, M. J.
Bibcode: 1993ASPC...42..141T
Altcode: 1993gong.conf..141T
  No abstract at ADS

Title: Sources of uncertainty in direct seismological measurements
    of the solar helium abundance
Authors: Kosovichev, A. G.; Christensen-Dalsgaard, J.; Daeppen, W.;
   Dziembowski, W. A.; Gough, D. O.; Thompson, M. J.
Bibcode: 1992MNRAS.259..536K
Altcode:
  The methods by which Dappen et al. (1988, 1990, 1991) and Dziembowski
  et al. (1990, 1991, 1992) recently obtained discrepant estimates of
  the helium abundance in the solar convection zone are compared. The
  aim of the investigation reported in this paper is to identify the
  main source of the discrepancy. Using as proxy data eigenfrequencies
  of a set of modes of a theoretical solar model, computed with the
  same physics as were the frequencies of a reference model with which
  these data are compared, the two methods yield similar results. Thus
  we ascertain that the principal source of the discrepancy is not in
  the inversions themselves, which yield essentially a measure of the
  variation of the adiabatic exponent gamma of the material in the He II
  ionization zone. Instead it is in the approximations adopted in the
  treatment of heavy elements in the equation of state used to relate
  the variation of gamma to chemical composition. We obtain acceptably
  consistent results when inverting solar data by two methods using the
  same equation of state. We attempt to identify the likely residual
  sources of uncertainty.

Title: On the rate of destruction of lithium in late-type
    main-sequence stars
Authors: Christensen-Dalsgaard, J.; Gough, D. O.; Thompson, M. J.
Bibcode: 1992A&A...264..518C
Altcode:
  It it shown that the rate of destruction of lithium by nuclear reactions
  in the outer mixed layers of late-type main-sequence stars depends on
  both the depth of the region where mixing occurs and the stratification
  within it. The mixed region includes and probably extends beneath the
  base of the convection zone. As the star evolves on the main sequence,
  the properties of the convection zone vary in a simple manner. If
  the mixed layer behaves similarly, then the mean destruction rate
  can easily be related to the present local value evaluated at the
  base of the mixed layer. In the case of the sun, it is found that if
  mixing is rapid compared with the nuclear destruction rate, then the
  mean destruction rate is approximately equal to one-half the present
  local value.

Title: On the effects of chromospheric magnetic perturbations on
    solar oscillation frequencies
Authors: Wright, A. N.; Thompson, M. J.
Bibcode: 1992A&A...264..701W
Altcode:
  A perturbation method is developed for calculating the effect
  on the frequencies of solar global oscillations of changes in the
  chromosphere. We show that the frequency perturbation depends on the
  subphotospheric structure of the solar model only through the mode
  inertia (or mode mass). The effects of changing the chromosphere can
  first be calculated independently of any particular model of the solar
  interior; and the frequency perturbations for any given model then
  obtained by scaling with mode inertia. In particular we apply the
  method to changes in chromospheric magnetic field.

Title: Faster formulations of the optimally localized averages method
    for helioseismic inversions
Authors: Pijpers, F. P.; Thompson, M. J.
Bibcode: 1992A&A...262L..33P
Altcode:
  Much use is made in helioseismology of the optimally localized averages
  method of inversion, introduced by Backus and Gilbert. However,
  the method is computationally expensive for large data sets. Here we
  present a class of alternative formulations of that method which are
  more efficient computationally and yet they retain the advantages of
  the method in its usual form.

Title: The Effect of an Inclined Magnetic Field on Solar Oscillation
    Frequencies
Authors: Goode, Philip R.; Thompson, Michael J.
Bibcode: 1992ApJ...395..307G
Altcode:
  The radiative interior of the sun could be hiding a large-scale magnetic
  field, which might not be axisymmetric about the observed rotation
  axis. Using helioseismic data, we estimate that the strength of any such
  relic field must be less than about 30 MG, if the field is axisymmetric
  about the rotation axis. The shape oblateness caused by a field at
  this limiting strength is about 5-10 x 10 exp -6. Stronger fields can
  be accommodated by the helioseismic data if they are inclined to the
  rotation axis. We further conclude that the convention zone and at
  least the outer part of the radiative interior rotate on the same axis.

Title: The Resolving Power of Current Helioseismic Inversions for
    the Sun's Internal Rotation
Authors: Schou, J.; Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1992ApJ...385L..59S
Altcode:
  An inversion of the currently available rotational splitting data
  which is representative of other recent inversions for the sun's
  internal rotation is analyzed. The so-called polar rate is found to be
  an extrapolation from lower latitudes. The basic conclusion that the
  average radial gradient of the rotation rate in the solar convection
  zone is small is corroborated.

Title: Does the Sun Rotate on a Single Axis?
Authors: Goode, Philip R.; Thompson, Michael J.
Bibcode: 1992ASPC...27..182G
Altcode: 1992socy.work..182G
  No abstract at ADS

Title: The Depth of the Solar Convection Zone
Authors: Christensen-Dalsgaard, J.; Gough, D. O.; Thompson, M. J.
Bibcode: 1991ApJ...378..413C
Altcode:
  The transition of the temperature gradient between being subadiabatic
  and adiabatic at the base of the solar convection zone gives rise to
  a clear signature in the sound speed. Helioseismic measurements of the
  sound speed therefore permit a determination of the location of the base
  of the convection zone. Two techniques were tested by applying them
  to artifical data, obtained by adding simulated noise to frequencies
  computed from two different solar models. The determinations appear to
  be relatively insensitive to uncertainties of the physics of the solar
  interior. From an analysis of observed frequencies of solar oscillation
  it is concluded that the depth of the solar convection zone is (0.287 +
  or - 0.003) solar radii.

Title: The Response of the Adiabatic Exponent Gamma 1 to Modifications
    of Solar Models
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.
Bibcode: 1991ApJ...367..666C
Altcode:
  Guenther et al. (1989) investigated the effet of varying the abundance
  of elemental Ne on solar models and found that the changes in some
  aspects of these models in the ionization zones of helium and hydrogen
  were nonmonotonic functions of the assumed Ne abundance. In this paper,
  the results of Guenther et al. are examined, and it is found that
  the apparent nonmonotonic behavior of the models was caused by slight
  errors in the radii of their models, combined with the fact that the
  adiabatic exponent Gamma(1) was compared at fixed distance r from the
  center of the model. When the models are compared at fixed fractional
  radius r/R, the differences in the values of Gamma(1) were found to
  behave in a much more regular way.

Title: Helioseismic Inversion
Authors: Thompson, M. J.
Bibcode: 1991LNP...388...61T
Altcode: 1991ctsm.conf...61T
  The application of inverse theory enables us to use the measured
  frequencies of normal modes of oscillation of the Sun to make inferences
  about the structure and dynamics of the solar interior. Some basic
  concepts and a few inversion techniques are discussed. Results on
  solar rotation and radial stratification are reviewed, and finally the
  potential for investigating other moderate-mass stars seismologically
  is considered.

Title: The inversion problem.
Authors: Gough, D. O.; Thompson, M. J.
Bibcode: 1991sia..book..519G
Altcode:
  The authors discuss some fundamental problems associated with inverting
  helioseismic data to infer properties of the solar interior, and
  review various methods used to invert frequencies of normal modes of
  oscillation. After discussing linear methods, the authors present and
  compare different asymptotic methods that have been used to infer the
  internal solar sound speed. They also discuss numerical inversions
  for solar structure, and address the issue of inverting for more than
  one function. Methods of inverting for the nonspherically symmetric
  structure of the Sun are presented.

Title: A New Inversion for the Hydrostatic Stratification of the Sun
Authors: Däppen, W.; Gough, D. O.; Kosovichev, A. G.; Thompson, M. J.
Bibcode: 1991LNP...388..111D
Altcode: 1991ctsm.conf..111D
  Inversions for the spherically symmetric component of the hydrostatic
  stratification of the Sun are presented. These employ the Backus-Gilbert
  optimally localized averaging procedure applied to oscillation multiplet
  frequencies in the range 1.5 - 3 mHz of modes with 4 l 140 determined
  by Libbrecht et al. (1990) from observations carried out in 1986. We
  also obtain an estimate of the helium abundance in the solar convective
  envelope.

Title: A comparison of methods for inverting helioseismic data
Authors: Christensen-Dalsgaard, J.; Schou, J.; Thompson, M. J.
Bibcode: 1990MNRAS.242..353C
Altcode:
  Consideration is given to the inversion techniques used to study the
  properties of the solar interior with observed frequencies of solar
  oscillation. Linear inversion schemes for helioseismic problems are
  compared in terms of resolutions and error properties. Measures of the
  error amplification resulting from the inversion and the resolution
  achieved are defined. Although the study includes only inversions for
  a spherically symmetric angular velocity distribution, it is suggested
  that the methods may be used to study kernels for other properties of
  the solar interior.

Title: The effect of rotation and a buried magnetic field on stellar
    oscillations
Authors: Gough, D. O.; Thompson, M. J.
Bibcode: 1990MNRAS.242...25G
Altcode:
  A perturbation method is presented for calculating the frequency
  modification of stellar oscillations caused by rotation and internal
  magnetic field. A short-wavelength asymptotic analysis derived from
  ray theory is also presented. The effects on high-order solar acoustic
  modes of various hypothetical angular velocity and magnetic field
  configurations are investigated using both methods of calculation. The
  asymptotic formulas provide a good estimate for the frequency splitting
  of five-minute modes when the field and the rotation vary sufficiently
  smoothly. On the other hand, a localized magnetic field, for example at
  the base of the convection zone, produces a characteristic oscillatory
  perturbation to the eigenfrequencies.

Title: A New Inversion of Solar Rotational Splitting Data
Authors: Thompson, M. J.
Bibcode: 1990SoPh..125....1T
Altcode:
  The fine structure of the solar p-mode spectrum is used to obtain
  an estimate of the Sun's internal rotation rate, as a function of
  both latitude and depth, for fractional radii in the range 0.55 &lt;
  r/R &lt; 0.85. Because each piece of data is a weighted average of
  the rotation rate over an extended region of the solar interior and
  because the number of such measurements is finite, such an inversion
  unavoidably has limited resolution and suffers from other systematic
  errors. Accordingly, the results of the inversion presented here
  and other published inversions should be interpreted with this in
  mind. These problems are discussed in detail for the present inversion.

Title: What are the Observed High-Frequency Solar Acoustic Modes?
Authors: Kumar, P.; Duvall, T. L., Jr.; Harvey, J. W.; Jefferies,
   S. M.; Pomerantz, M. A.; Thompson, M. J.
Bibcode: 1990LNP...367...87K
Altcode: 1990psss.conf...87K
  Jefferies et al. (1988) observe discrete peaks up to 7mHz in the power
  spectra of their intermediate degree solar intensity oscillation data
  obtained at South Pole. This is perhaps surprising since waves with
  frequency greater than the acoustic cut-off frequency at the temperature
  minimum ( 5.5mHz), unlike their lower frequency counterparts, are not
  trapped in the solar interior. We propose that the observed peaks are
  associated with what are principally progressive waves emanating from
  a broad-band acoustic source. The geometrical effect of projecting
  observations of these progressive waves onto spherical harmonics
  then gives rise to peaks in the power spectra. The frequencies and
  amplitudes of the peaks will depend on the spatial characteristics of
  the source. Partial reflections in the solar atmosphere modify the power
  spectra, but in this picture they are not the primary reason for the
  appearance of the peaks. We estimate the frequency and power which would
  be expected from this model and compare it with the observations. We
  argue that these high frequency mock-modes are not overstable, and
  that they are excited by acoustic emission from turbulent convection.

Title: Differential asymptotic sound-speed inversions
Authors: Christensen-Dalsgaard, J.; Thompson, M. J.; Gough, D. O.
Bibcode: 1989MNRAS.238..481C
Altcode:
  An asymptotic method for determining the internal solar sound speed
  from the differences between observed p-mode frequencies and those
  of a standard reference solar model is presented. In order to test
  the method, it has been applied to the frequency differences between
  pairs of solar models, where in each case one takes the part of the
  reference model and the other the role of the sun. The results of
  these numerical experiments indicate that by using this simple method
  one may in principle be able to determine the sound speed from the
  energy-generating core to the helium ionization zone.

Title: Determination of the solar internal sound speed by means of
    a differential asymptotic inversion.
Authors: Christensen-Dalsgaard, J.; Gough, Douglas O.; Thompson, M. J.
Bibcode: 1988ESASP.286..493C
Altcode: 1988ssls.rept..493C
  The authors present a simple asymptotic inversion method for
  obtaining an estimate of the difference in internal sound speed from
  differences between five-minute p-mode oscillation frequencies. Thus,
  given a known model and a set of frequencies of a model of unknown
  structure, or of the Sun, the internal sound speed of the latter can be
  estimated. Numerical experiments with error-free frequencies indicate
  that this method can provide an estimate of the sound speed, from the
  energy-generating core to the helium ionization zone, with smaller
  fractional error than any previously published results. The authors
  have applied the method to real solar data, and find that the solar
  sound speed is indeed broadly as determined by an earlier investigation
  at those depths for which the earlier inversion should be reliable.

Title: Evidence for a thin perturbative layer near the base of the
    solar convection zone.
Authors: Thompson, M. J.
Bibcode: 1988ESASP.286..321T
Altcode: 1988ssls.rept..321T
  Low-degree solar p-mode frequencies hint at the presence of a thin
  perturbative layer at the base of the Sun's convection zone. Magnetic
  flux stored in an overshoot region could constitute such a perturbative
  layer.

Title: Further progress on the helium abundance determination.
Authors: Daeppen, W.; Gough, Douglas O.; Thompson, M. J.
Bibcode: 1988ESASP.286..505D
Altcode: 1988ssls.rept..505D
  The authors report on further progress in attempting to determine the
  helium abundance in the solar convection zone by analysing the position
  and shape of the "helium hump" in a thermodynamic quantity Θ which
  can be inferred from the sound speed in the vicinity of the He II
  ionization zone. At present they are estimating the sound speed from
  frequencies of high-degree oscillations by a differential asymptotic
  technique. The helium abundance Y is then determined by fitting the hump
  inferred to one obtained by interpolation in a grid of theoretical model
  envelopes. They have tested the procedure by carrying out a double-blind
  experiment on artificial data, and have found that accurate knowledge
  of the equation of state is essential for a useful determination. The
  authors have also carried out the procedure on real solar data, but
  they judge that the frequencies are at present too poorly determined
  to enable us to obtain a reliable estimate of Y in the sun.

Title: On the Implications of the Symmetric Component of the
    Frequency Splitting
Authors: Gough, D. O.; Thompson, M. J.
Bibcode: 1988IAUS..123..175G
Altcode:
  The component of the frequency splitting of solar five-minute
  oscillations observed by Duvall, Harvey and Pomerantz that is even
  in azimuthal degree measures latitudinal and depth variations in the
  structure of the sun. The authors indicate how the data hint that there
  is a shallow perturbation, possibly associated with a magnetic field,
  that is concentrated at low latitudes.

Title: Magnetic Perturbations to Stellar Oscillation Eigenfrequencies
Authors: Gough, D. O.; Thompson, M. J.
Bibcode: 1988IAUS..123..155G
Altcode:
  Magnetic fields contribute to the splitting of the degeneracy of modes
  of like order and degree. The splitting is estimated for some simple
  hypothetical toroidal magnetic field configurations in the sun, and
  the results are compared with previous asymptotic estimates. Splitting
  by a field confined to a thin layer at the base of the convection zone
  is found not to agree with recent measurements.

Title: Problems in helioseismology
Authors: Thompson, Michael John
Bibcode: 1987PhDT........98T
Altcode:
  No abstract at ADS

Title: Communication. Enhanced sensitivity in the determination of
    mercury by inductively coupled plasma atomic-emission spectrometry
Authors: Thompson, Michael; Coles, Barry J.
Bibcode: 1984Ana...109..529T
Altcode:
  No abstract at ADS

Title: Post-Newtonian collapse calculations
Authors: Thompson, M.
Bibcode: 1983PASA....5..179T
Altcode: 1983PASAu...5..179T
  The dynamical collapse of a rotating body (with a mass less than the
  critical mass) from white dwarf densities down toward neutron star
  densities is examined with a view to resolving some of the effects of
  rotation on the evolution. In the approach used here, the post-Newtonian
  equations for continuity and momentum (Chandrasekhar, 1964) for a
  perfect fluid are modeled with the smoothed particle hydrodynamics of
  Gingold and Monagham (1982). The version of the code used conserves
  both linear and angular momentum exactly. Collapse calculations are
  carried out using a 1000-particle code. The results obtained are
  briefly discussed, and improvements to the code are suggested.

