Author name code: deubner
ADS astronomy entries on 2022-09-14
author:"Deubner, Franz-Ludwig" 
------------------------------------------------------------------------  

Title: Commission 12: Solar Radiation and Structure (Radiation et
    Structure Solaires)
Authors: Foukal, Peter; Solanki, Sami; Mariska, J.; Baliunas, S.;
   Dravins, D.; Duvall, T.; Fang, C.; Gaizauskas, V.; Heinzel, P.;
   Kononovich, E.; Koutchmy, S.; Melrose, D.; Stix, M.; Suematsu, Y.;
   Deubner, F.
Bibcode: 2000IAUTA..24...73F
Altcode:
  No abstract at ADS

Title: Observers' Views of the Bustling Atmosphere of the Sun
Authors: Deubner, F. -L.; Steffens, S.
Bibcode: 1999ESASP.448..149D
Altcode: 1999ESPM....9..149D; 1999mfsp.conf..149D
  No abstract at ADS

Title: Observational Constraints on Models of the Solar Background
    Spectrum
Authors: Straus, Th.; Severino, G.; Deubner, F. -L.; Fleck, B.;
   Jefferies, S. M.; Tarbell, T.
Bibcode: 1999ApJ...516..939S
Altcode:
  We discuss the properties of the solar background signal as observed in
  high-quality, l-ν power and phase difference spectra of the continuum
  (C), velocity (V), and line intensity (I) fluctuations of the Ni
  I 6768 Å line. These spectra were generated from high-resolution
  images acquired by the Michelson Doppler Imager on board SOHO. <P />We
  confirm that the background signal in the velocity power spectra can be
  reproduced by a composite model with two quasi-stationary components,
  describing large-scale and small-scale convective motions, and a
  periodic component. The line and continuum intensity power spectra
  require additional quasi-stationary and periodic components. The
  extra quasi-stationary component dominates the intensity and
  continuum background signals over the spectral region where the I-V
  phase difference spectra show essentially constant negative phase
  difference: i.e., below and in between the p-mode ridges (called the
  plateau-interridge regime by Deubner et al.). Since the I-V phase
  between the p-mode ridges is not random, the solar background beneath
  the p-modes must be considered as coherent. We thus speculate that
  the negative phase regime may be the manifestation of a correlated
  background. Such a background has been proposed to explain the opposite
  sense of the asymmetries of the p-mode line profiles in velocity and
  brightness oscillations.

Title: υ - υ Phase Relations in the Vicinity of the Transition
    Region Derived from SUMER Observations
Authors: Steffens, S.; Deubner, F.
Bibcode: 1999ASPC..183..426S
Altcode: 1999hrsp.conf..426S
  No abstract at ADS

Title: Astronomisches Institut der Universität
    Würzburg. Jahresbericht für 1998.
Authors: Deubner, F. -L.
Bibcode: 1999MitAG..82..751D
Altcode:
  No abstract at ADS

Title: A wavelet analysis of solar atmospheric oscillations - on
    the excitation of solar oscillations.
Authors: Yan, Yihua; Deubner, F. L.; Kleineisel, R.
Bibcode: 1998ArBei..32...41Y
Altcode:
  The mechanism that keeps the surface of the Sun in 5-min oscillations
  remains to be soundly confirmed by direct observations. The present
  study aims at working out, with an alternative approach, the 2-D
  response of the solar atmosphere to a local perturbation induced by
  impulsive convective motions. Using the wavelet transform, the authors
  provide an observed phase relationship between convective eddies and the
  atmospheric wave that helps to understand the energy exchange process.

Title: A spacial analysis of local sources of oscillations
Authors: Yan, Y.; Deubner, F. -L.; Kleineisel, R.
Bibcode: 1998IAUS..185..461Y
Altcode:
  A continuous wavelet transform has been used to study the interaction
  of impulsive and periodic perturbations in the solar atmosphere. The
  transform allows the characterization of waveforms together with the
  determination of the temporal delays that occur between the observed
  fluctuations. Without selecting sample events but using the whole
  observed data cubes, the research has confirmed the previous results of
  the observational study (Deubner &amp; Kleineisel 1996, etc.). Further,
  the phase relationship between convective eddies and the atmospheric
  waves is also studied with the help of the wavelet transform.

Title: Physics of the Sun and Heliosphere in the ERA of Space Probes:
    Scientific Highlights of SOHO, ULYSSES and Yohko
Authors: Engvold, O.; Deubner, F. L.; Ripken, H.
Bibcode: 1998HiA....11..827E
Altcode:
  No abstract at ADS

Title: Phase relations and other diagnostics of solar atmospheric
    strucutre and dynamics
Authors: Deubner, F. -L.
Bibcode: 1998IAUS..185..427D
Altcode:
  Our perception of dynamical processes of the solar atmosphere
  is presently characterized by the availability of highly advanced
  radiation-hydrodynamic models and simulations, tackling also the effects
  of small-scale magnetic fields, sunspots, canopies etc. on the one
  hand. On the other hand, we are confronted with puzzling difficulties,
  even under quiet solar surface conditions, in matching the observational
  results with detailed predictions from 1-D simulations. Obviously,
  momentum and energy transport in the real solar atmosphere cannot be
  satisfactorily described in 1-D radiation-hydrodynamic studies. However,
  the observations provide 3-D information on the amplitude, phase,
  wave form etc. of brightness fluctuation and Doppler shift due to
  wave motions, as function of frequency and wavenumber (viz. horizontal
  component of wave vector). They help to clearly distinguish e.g. running
  from standing waves, to detect reflected and scattered waves, and to
  separate local events from global oscillations. We discuss examples,
  how this large reservoir of experimental results may be utilized
  to supplement the diagnostic inventory presently being applied
  by theoretical studies, and to examine the productivity of current
  concepts of chromospheric dynamics.

Title: Astronomisches Institut der Universität
    Würzburg. Jahresbericht für 1997.
Authors: Deubner, F. -L.
Bibcode: 1998MitAG..81..737D
Altcode:
  No abstract at ADS

Title: Phase spectra seen from space
Authors: Straus, Th.; Deubner, F. -L.; Fleck, B.; Marmolino, C.;
   Severino, G.; Tarbell, T.
Bibcode: 1998IAUS..185..455S
Altcode:
  We discuss preliminary results of a study of the dynamics of the solar
  atmosphere including a first space based investigation of k-omega phase
  difference spectra between velocity and intensity perturbations. The
  data, including simultaneous line shift, line depth, and continuum
  intensity measurements at disk center, have been obtained from a MDI
  time series in its high resolution mode. Line depth and continuum
  intensity are used to calculate the line intensity which is the more
  frequently used parameter in phase difference studies. We compare the
  results to ground based observations.

Title: New eyes to see inside the sun and stars : pushing the limits
    of helio- and asteroseismology with new observations from the ground
    and from space
Authors: Deubner, Franz-Ludwig; Christensen-Dalsgaard, Joergen;
   Kurtz, Don
Bibcode: 1998IAUS..185.....D
Altcode:
  No abstract at ADS

Title: K-ϖ Phase Spectra Obtained from Space
Authors: Straus, Th.; Fleck, B.; Severino, G.; Deubner, F. -L.;
   Marmolino, C.; Tarbell, T.
Bibcode: 1998ESASP.417..293S
Altcode: 1998cesh.conf..293S
  No abstract at ADS

Title: The influence of the solar atmospheric stratification on the
    structure of the acoustic wave field
Authors: Steffens, S.; Schmitz, F.; Deubner, F. -L.
Bibcode: 1997SoPh..172...85S
Altcode: 1997ESPM....8...85S
  We investigate the influence of the solar atmospheric temperature
  stratification on the amplitude of waves at different heights and its
  dependence on frequency and wave number. Special interest is taken in
  the influence of atmospheric layers on the appearence of the recently
  observed p-mode crossing features and their location in the Fourier
  domain. We consider four stratification models. One of them is the
  standard model with convection-zone, VAL-atmosphere and corona. The
  others are modifications of this model in order to discuss the influence
  of specific layers of the atmosphere. The changes in the temperature
  structure significantly influence the velocity amplitude at certain
  frequency-wave number combinations at certain heights.

Title: Wave Propagation in the Chromosphere and Transition Region:
    Where Have All the Shock Waves Gone?
Authors: Fleck, B.; Steffens, S.; Deubner, F. -L.; Wilhelm, K.;
   Harrison, R.; Gurman, J.
Bibcode: 1997SPD....28.0120F
Altcode: 1997BAAS...29..882F
  We present first results from a joint observing program (SOHO JOP 26)
  involving SUMER, CDS and EIT on SOHO, coordinated with ground-based
  observations at the Vacuum Tower Telescope at Iza{\ n}a, Tenerife. The
  objective of this study is to characterize the wave propagation
  properties in the solar atmosphere, from the photosphere through the
  chromosphere up into the transition region. Particular emphasis is laid
  on the 3-min shock waves observed in the Ca II K line. How do they
  impact the transition region and what signature do they leave there
  and in the lower corona? The ground-based measurements comprise high
  resolution time series (both filtergrams and spectrograms) in Ca II K,
  Hα and Mgb_2. With SUMER we ran four sequences covering different
  temperature regimes: a) O I 1302, O I 1306, Si II 1309, C I 1311,
  C II 1334, C II 1335, b) Si I 1256, N V 1242, O V 629 c) He I 584,
  C III 1175, O I 1152, d) H I 1025, O VI 1031, O VI 1037. With CDS we
  took spectral time series in O VI 554, He I 584, He II 607, Mg IX 368,
  and O V 629 as well as wide-slit (90x240'') ``movies'' in He I 584,
  Mg IX 368 and O V 629, while EIT ran sub-field high cadence sequences
  in He II 304.

Title: First Results from SOHO on Waves Near the Solar Transition
    Region
Authors: Steffens, S.; Deubner, F. -L.; Fleck, B.; Wilhelm, K.;
   Schuhle, U.; Curdt, W.; Harrison, R.; Gurman, J.; Thompson, B. J.;
   Brekke, P.; Delaboudiniere, J. -P.; Lemaire, P.; Hessel, B.; Rutten,
   R. J.
Bibcode: 1997ASPC..118..284S
Altcode: 1997fasp.conf..284S
  We present first results from simultaneous observations with the
  CDS, EIT and SUMER instruments {please see Solar Physics 162 (1995)
  for a description of the instruments} onboard SOHO and the VTT at
  Tenerife. Our aim is to study the wave propagation, shock formation,
  and transmission properties of the upper chromosphere and transition
  region. The preliminary results presented here include the variation
  of velocity power spectra with height, difference in power between
  internetwork and network regions, and variations in mean flows displayed
  by different spectral lines.

Title: Astronomisches Institut der Universität
    Würzburg. Jahresbericht für 1996.
Authors: Deubner, F. -L.
Bibcode: 1997MitAG..80..703D
Altcode:
  No abstract at ADS

Title: An observational study of the interaction of impulsive and
    periodic perturbations in the solar atmosphere
Authors: Deubner, F. L.; Kleineisel, R.
Bibcode: 1997IAUS..181..307D
Altcode:
  No abstract at ADS

Title: Tracing CA K Grains Through the Chromosphere into the
    Transition Region
Authors: Steffens, S.; Deubner, F. -L.; Fleck, B.; Wilhelm, K.
Bibcode: 1997ESASP.404..685S
Altcode: 1997cswn.conf..685S
  No abstract at ADS

Title: Wave Propagation in the Chromosphere and Transition Region
Authors: Steffens, S.; Deubner, F. -L.; Fleck, B.; Wilhelm, K.;
   Harrison, R.; Gurman, J.
Bibcode: 1997ESASP.404..679S
Altcode: 1997cswn.conf..679S
  No abstract at ADS

Title: Division II: Sun &amp; heliosphere. Reports 1996 from IAU
    Commissions 10, 12 and 49.
Authors: Engvold, O.; Deubner, F. -L.; Ripken, H.
Bibcode: 1997IAUTA..23..119E
Altcode:
  Commissions 10: Solar activity, 12: Solar radiation &amp; structure,
  49: The interplanetary plasma &amp; the heliosphere.

Title: Reports from IAU Commission 12: Solar radiation &amp;
    structure.
Authors: Deubner, F. -L.
Bibcode: 1997IAUTA..23..149D
Altcode:
  No abstract at ADS

Title: Evidence of K_2v_ grains being a non-magnetic phenomenon.
Authors: Remling, B.; Deubner, F. -L.; Steffens, S.
Bibcode: 1996A&A...316..196R
Altcode:
  We present new data concerning the relation between locations of K_2v_
  grain appearance and magnetic flux tubes. The data consist of a two hour
  time series of simultaneous spectral scans in CaK and in the rotational
  bands of cyanogen (CN) around 3883A. The intensity near the CN bandhead
  at 3883.4A is used as a proxy for vertical magnetic flux (cf. Sheeley
  (1971SPh....20...19S), Liu &amp; Sheeley (1971SPh....20..282), Chapman
  (1974SPh....37..151C)). We find no statistically significant increase
  in CN intensity at locations of K_2v_ grain appearance. This indicates
  that there is no relation between small scale magnetic flux tubes and
  locations of bright K_2v_ grains in the internetwork region.

Title: Observations of resonant nonradial modes of the solar
    atmosphere
Authors: Deubner, F. -L.
Bibcode: 1996BASI...24..117D
Altcode:
  No abstract at ADS

Title: K-grains as a three-dimensional phenomenon. II. Phase analysis
    of the spatio-temporal pattern.
Authors: Hofmann, J.; Steffens, S.; Deubner, F. -L.
Bibcode: 1996A&A...308..192H
Altcode:
  We have observed spatially one- and two-dimensional time series of CaiiK
  spectra to study the spatio-temporal excitation pattern of the Ca K_2V_
  grains. We compare the phases of chromospheric velocity fluctuations
  (V) measured in K_3_ with those of spectral brightness measured at fixed
  wavelength intervals in K_2V_ and K_2R_ (I). Temporal crosscorrelation
  functions of prominent chromospheric (3min) wavetrains reproduce the
  commonly observed coincidence of brightness maxima in K_2V_ and extreme
  redshift of K_3_, whereas the corresponding V-I phases in the k-ν
  diagrams reveal a distinct dichotomy: Only in the gaps between the
  p-mode ridges do the spectra exhibit homogeneous areas with a stable
  phase of approximately 180deg in agreement with the crosscorrelation
  result. On the ridges the V-I phase switches to distinctly lower values
  near -90deg, with K_3_ redshift preceding K_2V_ brightening. The latter
  value is similar to the characteristic V-I phase measured in the core
  of other chromospheric lines. Our findings support the contention that
  a) K-grains are excited by superposition of resonant p-modes, and b)
  that p-modes exhibit a uniform signature of their dynamic behaviour
  throughout the full height range of the chromosphere.

Title: Dynamics of the solar atmosphere. VI. Resonant oscillations
of an atmospheric cavity: observations.
Authors: Deubner, F. -L.; Waldschik, T.; Steffens, S.
Bibcode: 1996A&A...307..936D
Altcode:
  We have evaluated new, spatially one- and two-dimensional time series
  of photospheric and chromospheric Fraunhofer lines at a large number
  of positions in the line profile, with the 'lambdameter' method. As
  a result we have obtained the velocity and brightness fluctuations
  corresponding to many closely staggered height levels in the atmosphere,
  and their respective phase spectra as a diagnostic of the wave fields
  involved. This material has not only served to define more accurately
  and specifically the character of the 180deg phase jump observed before
  in V-I spectra of the NaD_2_ line in internetwork regions, and to reveal
  the narrow height interval that gives rise to this discontinuity in
  the phase spectra. We have also discovered another discontinuity in
  V-V spectra of the same Fraunhofer line at nearly the same frequency
  (7.0mHz). Since neither running nor standing waves alone can explain
  the observed solitary phase discontinuities, our results provide
  strong evidence in favour of an atmosphere that supports (at least,
  and probably more than) one eigenmode as a component of the wave field.

Title: K-grains as a three-dimensional phenomenon. I. Statistics
    and spatial evolution.
Authors: Steffens, S.; Hofmann, J.; Deubner, F. L.
Bibcode: 1996A&A...307..288S
Altcode:
  We present new data concerning the statistics and motion of
  chromospheric K-grains, in order to verify possible excitation
  mechanisms. We have analysed a time-series of Ca K_2v_ filtergrams
  obtained with the VTT at Observatorio del Teide, Tenerife. K-grains are
  not only characterised by their brightness but also by their pointlike
  appearance and in some cases by a horizontal motion. Our statistical
  analysis of the spatial distribution of bright point emission reveals no
  significant clustering at particular areas in the internetwork. Some of
  the observed grains travel through the chromospheric internetwork cells
  with a speed comparable to the phase speed of the solar p-modes. Both
  results seem to be inconsistent with a causal relation between Ca K
  bright points and magnetic flux tubes, and rather favour a mechanism
  related to p-mode interference. Finally we present statistical evidence
  showing that bright points do not dominate the emission of the quiet
  chromosphere but rather contribute only about 9 percent of the K_2v_
  intensity emitted from the internetwork areas in our data.

Title: Astronomisches Institut der Universität
    Würzburg. Jahresbericht für 1995.
Authors: Deubner, F. -L.
Bibcode: 1996MitAG..79..669D
Altcode:
  No abstract at ADS

Title: The effect of limited spatial resolution on the observed
    power of solar oscillations.
Authors: Hofmann, J.; Deubner, F. -L.
Bibcode: 1995A&AS..113..583H
Altcode:
  We present an analysis of the rms amplitude of p-mode oscillations for
  different heights in the solar atmosphere, as a function of spatial
  resolution. Two different reduction methods are used to simulate
  limited spatial resolution. The dependence on spatial resolution can
  be approximated by power laws. We do not find significant differences
  between the exponents of the power laws obtained for the various
  spectral lines we have analysed. Also, the results of the two reduction
  methods differ only by a small amount.

Title: Is there a chromospheric mode at 6 mHz?
Authors: Steffens, S.; Deubner, F. -L.; Hofmann, J.; Fleck, B.
Bibcode: 1995A&A...302..277S
Altcode:
  We present time series of Na D_1_ and Ca K_2v_ filtergrams of the
  quiet sun obtained simultaneously with the Vacuum Tower Telescope at
  Observatorio del Teide, Tenerife. Special interest is taken in the
  distribution of power in the Fourier domain. We distinguish power
  "on" and "between" the ridges of the p-modes and pseudo p-modes. The
  latter are found to extend beyond the acoustic cutoff frequency up to
  12mHz in Na D_1_ and 8.5mHz in Ca K_2v_. Most of the power of the broad
  chromospheric feature detected in Ca II K by Harvey et al. (???) in the
  background of a one-dimensional power spectrum is found preferentially
  between the p-mode ridges at about 6mHz, as our two-dimensional analysis
  reveals. This behaviour would be consistent with the nature of "avoided
  crossing" (Ulrich &amp; Rhodes ???) of a chromospheric mode and the
  p-modes. We note that the center frequency of the interridge feature
  appears independent of height, whereas the power distribution of the
  p-mode ridges extends to higher frequencies as height increases. We
  suppose that different mechanisms are responsible for the generation of
  these two wave fields. In our investigation the broad band of enhanced
  power at 6mHz is even more conspicuous in Na D_1_ than in Ca K_2v_.

Title: Phase Analysis of the K-Grain Excitation Pattern
Authors: Hofmann, J.; Deubner, F. –L.; Steffens, S.; Fleck, B.
Bibcode: 1995ESASP.376b.493H
Altcode: 1995help.confP.493H; 1995soho....2..493H
  No abstract at ADS

Title: On the Phenomenology of K-Grains
Authors: Steffens, S.; Deubner, F. –L.; Hofmann, J.; Fleck, B.
Bibcode: 1995ESASP.376b.487S
Altcode: 1995soho....2..487S; 1995help.confP.487S
  No abstract at ADS

Title: Is There an Atmospheric Mode Near 6 mHz?
Authors: Steffens, S.; Deubner, F. –L.; Hofmann, J.; Fleck, B.
Bibcode: 1995ESASP.376b.481S
Altcode: 1995soho....2..481S; 1995help.confP.481S
  No abstract at ADS

Title: Is there an atmospheric mode near 6 mHz?
Authors: Steffens, S.; Deubner, F. -L.; Hofmann, J.; Fleck, B.
Bibcode: 1995AGAb...11..138S
Altcode:
  No abstract at ADS

Title: He 10830 Angstrom Confirms Non-Propagation Component of
    Chromospheric Oscillations
Authors: Hofmann, J.; Deubner, F. -L.; Fleck, B.
Bibcode: 1995ASPC...76..342H
Altcode: 1995gong.conf..342H
  No abstract at ADS

Title: What Have We Learned About Chromospheric Oscillations from
    HeI 10830Å?
Authors: Fleck, B.; Deubner, F. -L.; Hofmann, J.
Bibcode: 1995itsa.conf..437F
Altcode:
  Time series of He I 10830 spectra taken simultaneously with spectra
  of other chromospheric lines (Ca II 8542 Å and Ca II K) are analyzed
  to study wave propagation in the solar chromosphere. Rather than
  providing conclusive answers to some of the long standing questions
  concerning chromospheric oscillations, the new results derived from
  the He 10830 line raise new puzzling questions. The spatio-temporal
  wave pattern deduced from the Doppler displacements of the He line
  differs significantly from those of the two Ca II lines, while the
  phase difference between the Doppler displacements of He 10830 and Ca
  K_3 stays close to zero in the whole frequency range observed. This
  is difficult to reconcile with the low oscillation amplitude observed
  in the He 10830 line (RMS≈1100 m/s), which is less than half the
  velocity amplitude derived from the core displacement of Ca K_3. Another
  surprising result is that the Ca K ``bright point'' events are only
  barely visible in the Doppler displacement of the He 10830 line.

Title: Waves and Oscillations in the Solar Chromosphere
Authors: Deubner, F. -L.
Bibcode: 1995ASPC...76..303D
Altcode: 1995gong.conf..303D
  No abstract at ADS

Title: Resonant oscillations of the solar atmospheric cavity.
Authors: Deubner, F. -L.; Waldschik, T.; Steffens, S.
Bibcode: 1995AGAb...11..139D
Altcode:
  No abstract at ADS

Title: On the phenomenology of K-grains.
Authors: Steffens, S.; Deubner, F. -L.; Hofmann, J.; Fleck, B.
Bibcode: 1995AGAb...11..140S
Altcode:
  No abstract at ADS

Title: Astronomisches Institut der Universität
    Würzburg. Jahresbericht für 1994.
Authors: Deubner, F. -L.
Bibcode: 1995MitAG..78..587D
Altcode:
  No abstract at ADS

Title: On the strength of solar intra-network fields.
Authors: Keller, C. U.; Deubner, F. -L.; Egger, U.; Fleck, B.; Povel,
   H. P.
Bibcode: 1994A&A...286..626K
Altcode:
  The combination of the German Vacuum Tower Telescope and the prototype
  of ZIMPOL I (Zuerich Imaging Stokes Polarimeter I), a novel, very
  sensitive imaging polarimeter, has resulted in the first spectra
  of solar intra-network (IN) fields in circular polarization. The
  sensitivity in terms of flux density is 0.7 Mx/cm^2^. While magnetic
  fields in solar spots, pores, plages, and in the network have
  predominantly kG field strengths, the magnetic field strength of
  the IN flux is a controversial subject due to the absence of direct
  measurements. We first summarize the current ideas on IN fields and
  examine previous arguments for their field strength. Our measurements
  of the magnetic line ratio formed between the amplitudes of the Stokes
  V profiles of Fe I 5247.1 A and Fe I 5250.2 A are consistent with a
  field strength well below 1 kG. Since the sensitivity of the magnetic
  line ratio becomes low for small field strengths, we can only set an
  upper limit on the field strength of IN fields of 500 G at the level
  of line formation with a probability of 68% and an upper limit of 1
  kG with a probability of 95%. We emphasize that these are the first
  observations of a magnetic line ratio of unity near disk center.

Title: On the correlation of magnetic field strength and inclination
    with continuum brightness of a sunspot penumbra.
Authors: Hofmann, J.; Deubner, F. -L.; Fleck, B.; Schmidt, W.
Bibcode: 1994A&A...284..269H
Altcode:
  A fairly regular sunspot penumbra has been observed near disk center
  using a Stokes V polarimeter at the German Vacuum-Tower-Telescope in
  Izana, Tenerife. We obtained two-dimensional spectral data by scanning
  the limbside sector of the penumbra in steps of 1 arcsecond with the
  slit oriented parallel to the solar limb. From Stokes V and Stokes I
  spectra of four magnetically sensitive lines (FeI5247.1A, CrI5247.6A,
  FeI5250.2A, and FeI5250.7A) recorded with 1024 x 1024 pixel CCD
  cameras we have determined several magnetic parameters. The results
  of a correlation analysis show a clear relation between continuum
  brightness and magnetic field inclination, field lines beeing flatter
  in the dark penumbral filaments. We also find a correlation between
  field strength and brightness; this correlation is not uniform across
  the penumbra, however.

Title: Non-linearities of chromospheric oscillations
Authors: Deubner, F. -L.; Hofmann, J.; Kossack, E.; Fleck, B.
Bibcode: 1994ASIC..433..155D
Altcode:
  No abstract at ADS

Title: Observations of Low Wavenumber Nonradial Eigenmodes of the Sun
Authors: Deubner, F. -L.
Bibcode: 1994snft.book..402D
Altcode:
  No abstract at ADS

Title: Observations of Solar Oscillations in He 110830 Angstrom
Authors: Fleck, B.; Deubner, F. -L.; Maier, D.; Schmidt, W.
Bibcode: 1994IAUS..154...65F
Altcode:
  No abstract at ADS

Title: Wave propagation in the solar chromosphere: some new results
    from CaII K, CaII 8542 and HeI 10830 observations
Authors: Fleck, B.; Deubner, F. -L.; Hofmann, J.; Steffens, S.
Bibcode: 1994chdy.conf..103F
Altcode:
  Time series of spectra taken simultaneously in the three chromospheric
  lines Ca II 8542 A, Ca II K, and He I 10830 AA are analyzed to study
  the wave propagation behaviour in the solar chromosphere. The V-V
  phase difference between the three chromospheric lines stays close to
  0 deg in the whole frequency range observed and thus confirms previous
  observations of a non-propagating component dominating the acoustic
  wave spectrum in the solar chromosphere. In particular, the dominant
  3-min oscillations observed in the core displacement of the Ca II
  8542 and Ca K line are highly correlated, contrary to the numerical
  NLTE radiating shock dynamic simulations of Carlsson and Stein (1993)
  which revealed a significant phase delay between the two lines. The
  oscillation amplitude observed in the He 10830 line (RMS ~ 1100 m/s)
  is only about half the velocity amplitude derived from the core
  displacement of Ca K3. We also present a first He 10830 k-omega diagram.

Title: Ground — based instrumentation
Authors: Deubner, Franz Ludwig
Bibcode: 1994LNP...432..285D
Altcode: 1994LNPM...11..287D; 1994LNP...432..285L
  In parallel with the development and deployment of solar space
  instrumentation a substantial effort is being made at many ground
  based observatories world-wide, not only to make better use of the
  available hours of sunshine, but also to reach out to new frontiers of
  solar research. Examples of novel instrumentation will be described,
  and some of the observational results will be discussed in the light
  of current problems in solar physics.

Title: Line profile asymmetries in a sunspot penumbra
Authors: Hofmann, J.; Deubner, F. -L.; Fleck, B.
Bibcode: 1994smf..conf..182H
Altcode:
  No abstract at ADS

Title: Ground - based instrumentation.
Authors: Deubner, F. -L.
Bibcode: 1994LNP...432..287D
Altcode:
  In parallel with the development and deployment of solar space
  instrumentation a substantial effort is being made at many ground
  based observatories world-wide, not only to make better use of the
  available hours of sunshine, but also to reach out to new frontiers
  of solar research. Examples of novel instrumentation are described,
  and some of the observational results are discussed in the light of
  current problems in solar physics.

Title: Institut für Astronomie und Astrophysik der Universität
    Würzburg. Jahresbericht für 1993.
Authors: Deubner, F. -L.
Bibcode: 1994MitAG..77..505D
Altcode:
  No abstract at ADS

Title: Phases and amplitudes of acoustic-gravity waves. 2: The
    effects of reflection
Authors: Marmolino, C.; Severino, G.; Deubner, F. -L.; Fleck, B.
Bibcode: 1993A&A...278..617M
Altcode:
  We study wave reflection caused by the temperature stratification
  of the solar atmosphere, assumed to be a succession of two layers
  of different temperatures and radiative decay times. Considering
  waves which propagate energy upward in the atmosphere, we compute
  the complex amplitude reflection and transmission coefficients and
  investigate the effects that reflection introduces on the phases of
  acoustic-gravity waves. In the evanescent region of the k<SUB>x</SUB>
  - omega diagram, between the Lamb waves and the acoustic cut-off
  frequency, the reflection coefficient is small, in particular zero on
  the fundamental mode. Therefore, in this region, the reflected wave
  has a small amplitude and its superposition to the incident wave does
  not affect the latter in a significant way. In particular, the T - V
  phase differences of the total wave are very similar to those of the
  incident wave. Furthermore, a heruisitic formula is presented which
  describes the observed coexistence of two different phase regimes
  between velocity and intensity oscillations in the evanescent area
  above the fundamental mode.

Title: Polanmetric Measurements of the Fine Structure of a Sunspot
    Penumbra
Authors: Hofmann, J.; Deubner, F. L.; Fleck, B.
Bibcode: 1993ASPC...46...44H
Altcode: 1993mvfs.conf...44H; 1993IAUCo.141...44H
  No abstract at ADS

Title: Observations of Waves and Oscillations in the Solar Magnetic
    Fine Structure
Authors: Fleck, B.; Deubner, F. -L.; Schmidt, W.
Bibcode: 1993ASPC...46..522F
Altcode: 1993IAUCo.141..522F; 1993mvfs.conf..522F
  No abstract at ADS

Title: Institut für Astronomie und Astrophysik der Universität
    Würzburg.
Authors: Deubner, F. -L.
Bibcode: 1993MitAG..76..449D
Altcode:
  No abstract at ADS

Title: Dynamics of the solar atmosphere. V - Partial reflection and
    forced oscillation, and their signature in phase diagrams
Authors: Deubner, F. -L.; Fleck, B.; Schmitz, F.; Straus, Th.
Bibcode: 1992A&A...266..560D
Altcode:
  An overview of several new dynamic phenomena detected by means of
  velocity-brightness (V-I) and V-V phase diagrams is presented. The great
  diagnostic value of this kind of data analysis is demonstrated and used
  in order to develop a consistent description and interpretation of the
  surprisingly broad spectrum of linear hydrodynamic wave motions that
  occur in a stellar atmosphere. The significance of partial reflection
  and the role of forced oscillations in practically all layers of the
  solar atmosphere are demonstrated. With reference to the concept of
  continuous partial reflection, a model of the 'background' of coherent
  wave motions found at frequencies and wavenumbers in between the
  well-known p-mode ridges is presented.

Title: Is mesogranulation a distinct regime of convection?
Authors: Straus, Th.; Deubner, F. -L.; Fleck, B.
Bibcode: 1992A&A...256..652S
Altcode:
  We investigate the dynamics of the mesogranulation phenomenon by
  analyzing spatially 2D spectral time series taken at disk center
  and cos Theta = 0.8. After a 3D Fourier transformation, we integrate
  the power and crosspower spectra in azimuth, and calculate k - omega
  power, phase difference, and cross-power spectra. The spatial power
  spectra are compared with those obtained from numerical simulations of
  stationary cell patterns. In the deepest atmospheric layers the V - I
  phase difference spectra reveal a uniform regime of convective motions
  at frequencies below the Lamb mode. The power spectra exhibit at all
  levels a significant distinction between supergranulation and convective
  patterns of smaller scales. On the other hand, the 'mesogranulation'
  phenomenon cannot be identified as an independent convective regime
  in the deep photosphere, distinct from granulation. Rather, the
  mesostructures that appear to emerge in the middle photosphere and
  temperature minimum seem to be a product of the overshoot driving only
  the largest elements of an extended distribution of granular sizes
  while the smaller elements have already died out at a lower level.

Title: Polarimetric measurements of the fine structure of a sunspot
    penumbra.
Authors: Hofmann, J.; Deubner, F. -L.; Fleck, B.; Schmidt, W.
Bibcode: 1992AGAb....7..149H
Altcode:
  No abstract at ADS

Title: An analysis of non-linear oscillations in the solar
    chromosphere.
Authors: Kossack, E.; Deubner, F. -L.; Fleck, B.
Bibcode: 1992AGAb....7..148K
Altcode:
  No abstract at ADS

Title: Institut für Astronomie and Astrophysik, Lehrstuhl
    Astronomie. Jahresbericht für 1991.
Authors: Deubner, F. -L.
Bibcode: 1992MitAG..75..405D
Altcode:
  No abstract at ADS

Title: Observations of Waves and Oscillations in Solar Magnetic
    Fluxtube Concentrations (With 1 Figure)
Authors: Fleck, B.; Deubner, F. -L.
Bibcode: 1991mcch.conf...19F
Altcode:
  No abstract at ADS

Title: Oscillation observations.
Authors: Hill, Frank; Deubner, Franz-Ludwig; Isaak, George
Bibcode: 1991sia..book..329H
Altcode:
  This chapter reviews recent observations of solar oscillations. The
  oscillations discussed are global and local 5-min p-modes, the 160-min
  oscillation and oscillations in the solar atmosphere. Experimental
  and data reduction methods are described. Summaries of recent results
  are provided, including measurements of frequencies, amplitudes, line
  widths and splittings. Other topics include active-region tomography,
  solar cycle changes, the chromospheric cavity and diameter measurements.

Title: Observations of Waves and Oscillations (With 2 Figures)
Authors: Deubner, F. -L.
Bibcode: 1991mcch.conf....6D
Altcode:
  No abstract at ADS

Title: Institut für Astronomie und Astrophysik, Lehrstuhl
    Astronomie. Jahresbericht für 1990.
Authors: Deubner, F. -L.
Bibcode: 1991MitAG..74..379D
Altcode:
  No abstract at ADS

Title: Observations of solar oscillations
Authors: Deubner, Franz-Ludwig
Bibcode: 1991GApFD..62..153D
Altcode:
  The most recent observational activities and results in the field
  of solar oscillations are reviewed. We address the dynamics and
  structure of the solar interior and of the atmosphere up to the
  transition layer, while global, local and atmospheric oscillations
  are being discussed. The topics of this review include: line width and
  amplitude limits of the p-modes; cycle variations of frequencies and
  amplitudes; internal solar rotation rate; p-mode absorption in spots
  and antipodal focussing of p-modes; diagnostics in the UV and in the
  IR; phase diagnostics in the atmosphere; chromospheric bright points.

Title: Dynamics of the solar atmosphere. IV - Evanescent waves of
    small amplitude
Authors: Deubner, F. -L.; Fleck, B.; Marmolino, C.; Severino, G.
Bibcode: 1990A&A...236..509D
Altcode:
  The phase spectra of velocity and brightness perturbations in the quiet
  photosphere have been studied in the evanescent domain of the k-omega
  diagram. A regime of low-amplitude evanescent motions, occupying a
  large sector of the diagnostic diagram bordered by the Lamb and the
  fundamental mode, has been discovered. This regime forms a continuum
  in the k-omega plane, in contrast to the 5-min oscillations. Beyond the
  fundamental mode, it extends to much higher frequencies in between the
  power ridges of the resonant p-modes. It is suggested that the observed
  V-I phase is characteristic of evanescent waves, whose progressive
  part carries energy downward, and that a continuum of such waves is
  produced through scattering of ordinary resonant p-modes at higher
  levels in the atmosphere.

Title: Dynamics of the solar atmosphere. III - Cell-network
    distinctions of chromospheric oscillations
Authors: Deubner, F. -L.; Fleck, B.
Bibcode: 1990A&A...228..506D
Altcode:
  The propagation of waves in the chromosphere is analyzed, with
  focus placed on the differences between the bright boundaries of the
  chromospheric network and the dark cell interior. The logarithmic
  velocity and intensity power spectra of Ca 8542 and Ca 8498 are
  presented, along with the velocity fluctuations of Ca 8542 at a
  spatially resolved point in a cell center. Attention is focused
  on the phase difference and coherence spectra between the velocity
  fluctuations of Ca 8542 and Ca 8498 and Ca 8542 and the photospheric
  Fe 8496 line, as well as on the V - I phase and coherence spectra of
  the Ca lines. Significant differences in both power and phase spectra
  are found in the main power range from 3 to 6 mHz and also at low
  frequencies below 3 mHz and in the high-frequency range up to at least
  10 mHz. It is shown that the evanescent waves are influenced by the
  magnetic field in the cell boundaries.

Title: k-ω diagrams of the solar atmosphere revisited.
Authors: Deubner, F. -L.; Fleck, B.; Schmitz, F.; Straus, T.
Bibcode: 1990AGAb....5...35D
Altcode:
  No abstract at ADS

Title: Waves and Oscillations in the Non-Magnetic Photosphere
Authors: Deubner, F. -L.
Bibcode: 1990IAUS..138..217D
Altcode:
  No abstract at ADS

Title: Dynamics of mesogranulation.
Authors: Straus, T.; Deubner, F. -L.
Bibcode: 1990AGAb....5...34S
Altcode:
  No abstract at ADS

Title: Institut für Astronomie und Astrophysik, Lehrstuhl Astronomie.
Authors: Deubner, F. -L.
Bibcode: 1990MitAG..73..325D
Altcode:
  No abstract at ADS

Title: Comments on Solar Convection
Authors: Deubner, Franz-L.
Bibcode: 1990ASSL..159..117D
Altcode: 1990insu.conf..117D; 1990IAUCo.121..117D
  No abstract at ADS

Title: Observations of waves and oscillations in solar fluxtube
    concentrations.
Authors: Fleck, B.; Deubner, F. -L.
Bibcode: 1990PDHO....7..306F
Altcode:
  The authors investigate the dynamical behaviour of magnetic fluxtubes
  concentrations by analyzing a high spatial resolution time series of
  spectra taken simultaneously in left-hand and right-hand circularly
  polarized light. All parameters extracted from the Stokes V and Stokes
  I profiles reveal significant spatio-temporal variations.

Title: Dynamics of the solar atmosphere. II - Standing waves in the
    solar chromosphere
Authors: Fleck, B.; Deubner, F. -L.
Bibcode: 1989A&A...224..245F
Altcode:
  A time series of brightness and velocity fluctuations measured
  simultaneously in three Fraunhofer lines (Ca II 8542, Ca II 8498, Fe I
  8496) is analyzed to investigate the oscillatory behavior of the solar
  chromosphere. The propagation characteristics of waves in the average
  chromosphere are examined. Apart from nonpropagating oscillations near
  6 mHz, the results strongly suggest the existence of a standing wave
  pattern for the whole continuum of acoustic waves with frequencies
  beyond the acoustic cut-off frequency.

Title: Mesogranulation - a convective phenomenon
Authors: Deubner, F. L.
Bibcode: 1989hsrs.conf..489D
Altcode:
  No abstract at ADS

Title: Gravity waves
Authors: Deubner, F. L.; Fleck, B.
Bibcode: 1989hsrs.conf..339D
Altcode:
  No abstract at ADS

Title: Mesogranulation - A convective phenomenon
Authors: Deubner, Franz-Ludwig
Bibcode: 1989A&A...216..259D
Altcode:
  The dynamic behavior of mesogranulation at photospheric layers is
  investigated. A distinct regime of coherent velocity and brightness
  fluctuations is noted in the 4.5-10-arcsec range of spatial scales. The
  observed phases are consistent with those that are expected for
  hydrodynamic flows near the bottom of a stably stratified atmosphere. A
  smooth transition of phases is noted between the granular and the
  meso regime. The ratio of horizontal/radial flow velocity is shown
  to gradually increase with the element size over the whole range,
  suggesting that the mesogranules are convective in nature.

Title: Dynamics of the solar atmosphere. I - Spatio-temporal analysis
    of waves in the quiet solar atmosphere
Authors: Deubner, F. -L.; Fleck, B.
Bibcode: 1989A&A...213..423D
Altcode:
  A time series of simultaneously measured velocity (V) and intensity
  (I) fluctuations of different spectral lines formed in the photosphere
  and low chromosphere is analyzed. In order to separate the different
  patterns of motions, V-V and V-I phase difference spectra have been
  computed not only with respect to frequency but also to the horizontal
  wavenumber. The V-V phase difference spectra of the Na D1 line and two
  photospheric Fe I lines clearly show the existence of gravity waves in
  the solar atmosphere. The V-I phase spectra also exhibit the behavior
  of gravity waves at high wavenumbers. At low wavenumbers one finds
  positive V-I phase differences. This is taken as an indication for
  convective motions with a typical spatial scale of more than 5 arcsec
  (mesogranulation).

Title: Spatio-Temporal Analysis of Waves in the Solar Atmosphere
Authors: Deubner, F. -L.; Fleck, B.
Bibcode: 1989ASIC..263..325D
Altcode: 1989ssg..conf..325D
  No abstract at ADS

Title: Institut für Astronomie und Astrophysik, Lehrstuhl
    Astronomie. Jahresbericht für 1988.
Authors: Deubner, F. -L.
Bibcode: 1989MitAG..72..309D
Altcode:
  No abstract at ADS

Title: Granulation and Waves?
Authors: Deubner, F. -L.
Bibcode: 1989ASIC..263..195D
Altcode: 1989ssg..conf..195D
  No abstract at ADS

Title: GOLF: Global Oscillations at Low Frequencies for the SOHO
    mission
Authors: Gabriel, A. H.; Bocchia, R.; Bonnet, R. M.; Cesarsky, C.;
   Christensen-Dalsgaard, J.; Dame, L.; Delache, Ph.; Deubner, F. L.;
   Foing, B.; Fossat, E.
Bibcode: 1988sohi.rept...13G
Altcode:
  The GOLF (global oscillations at low frequencies) SOHO (solar
  heliospheric observatory) mission is described. It aims to study
  the internal structure of the Sun by measuring the spectrum of free
  global oscillations. GOLF will measure both p and g mode oscillations,
  with emphasis on low order long period waves which penetrate the
  solar core. The instrument aims to measure frequencies between 10-7
  and 6 10-3 Hz, with a sensitivity of 1 mm/s. The method involves an
  extension to space of the ground based technique for measuring the mean
  line-of-sight velocity of the solar surface. A sodium vapor resonance
  scattering filter is used in a longitudinal magnetic field to sample the
  two wings of the solar absorption line. The use of a modulating magnetic
  field provides a continuous internal calibration of the sensitivity. By
  adding an additional rotating polarizer, measurements are also made
  of the average solar magnetic field. Efforts are made to correct the
  data for the spurious effects caused by solar magnetic active regions.

Title: Has turbulent granular decay been observed?
Authors: Deubner, F. -L.
Bibcode: 1988A&A...204..301D
Altcode:
  Spatial wavenumber spectra of velocity and brightness fluctuations in
  solar photospheric spectral lines have been studied with particular
  attention to the range of spatial scales from 1arcsec.5 to 0arcsec.8,
  where the coherence of the spectra drops significantly. The author
  has found good coherence of brightness and outward velocity in the
  low photosphere to k-values of at least 8 Mm<SUP>-1</SUP>. At higher
  wavenumbers, the fluctuations are still correlated and an evidence of
  turbulent motions is not seen. Loss of coherence at high wavenumbers
  is likely to be caused by internal gravity waves.

Title: Observations of Solar Oscillations
Authors: Deubner, Franz-Ludwig
Bibcode: 1988ASSL..148..163D
Altcode: 1988pmls.conf..163D
  Recent progress in the field of helioseismology is reviewed. New
  results from observations of the global p-mode spectrum and some of
  their theoretical implications are considered as well as atmospheric
  eigenmodes and running waves in the visible part of the solar
  atmosphere.

Title: On the Energy of Shortperiod Acoustic Waves in the Solar
    Atmosphere
Authors: Deubner, F. L.; Reichling, M.; Langhanki, R.
Bibcode: 1988IAUS..123..439D
Altcode:
  The apparent Doppler shift amplitudes measured in the cross power
  spectra are compared with those of synthetic solar line profiles to
  yield estimates of the energy carried by short period waves at various
  photospheric/chromospheric levels.

Title: Erfordernisse und Möglichkeiten zeitlicher Auflösung
Authors: Deubner, F. -L.
Bibcode: 1987MitAG..68..166D
Altcode:
  No abstract at ADS

Title: Raum-zeitliche Analyse hydrodynamischer Wellenfelder in der
    Sonnenatmosphäre
Authors: Deubner, F. -L.; Fleck, B.
Bibcode: 1987MitAG..70..326D
Altcode:
  No abstract at ADS

Title: Observations of gravity waves in the solar atmosphere
Authors: Deubner, F. -L.
Bibcode: 1986ASIC..169...81D
Altcode: 1986ssds.proc...81D
  No abstract at ADS

Title: Is there an anisotropy of p-modes?
Authors: Deubner, F. -L.
Bibcode: 1986ASIC..169...83D
Altcode: 1986ssds.proc...83D
  No abstract at ADS

Title: Detection of Magneto-Gravity Waves in the Chromosphere
Authors: Deubner, F. L.
Bibcode: 1985tphr.conf..160D
Altcode:
  No abstract at ADS

Title: Oscillations as a diagnostic of chromospheric structure.
Authors: Deubner, F. -L.
Bibcode: 1985cdm..proc..279D
Altcode:
  No abstract at ADS

Title: Detection of magneto-gravity waves in the chromosphere.
Authors: Deubner, F. -L.
Bibcode: 1985MPARp.212..160D
Altcode:
  It has been shown that the brightness of the chromospheric network is
  correlated to the local power of velocity and brightness oscillations
  with periods longer than about 400 s, as measured in chromospheric
  lines (Ca II, H, K or IR triplet). This correlation does not hold if
  the oscillations are measured at a lower photospheric level.

Title: Phase-spectra of solar oscillations
Authors: Staiger, J.; Mattig, W.; Schmieder, B.; Deubner, F. -L.
Bibcode: 1984MmSAI..55..147S
Altcode:
  Diode array measurements of intensity- and velocity-oscillations
  were made at the coude-telescope of Capri. From these observations
  phase-spectra were calculated to identify different types of waves
  within the solar atmosphere. The results indicate the existence of
  atmospheric gravity modes in the frequency-range below 2.5 mHz. No
  running acoustic waves were found in the photosphere for frequencies
  beyond 7.5 mHz. Vertical propagation seems only to take place for
  frequencies between 5 mHz and 7.5 mHz. No vertical propagation at
  all was found in the upper chromosphere. This seems to be due to the
  occurrence of wave reflection at the chromosphere-corona interface.

Title: Phase relations of high degree modes revisited
Authors: Deubner, F. -L.; Endler, F.; Staiger, J.
Bibcode: 1984MmSAI..55..135D
Altcode:
  Preliminary results of spectral analyses revealing short-period
  oscillations of the solar atmosphere are reported. The numerical
  techniques developed by Endler and Deubner (1983) to compensate for
  the strongly nonrandom noise signal due to seeing effects in the phase
  spectra of various Fraunhofer lines are summarized, and synthetic phase
  spectra are presented and compared with observations. The signatures of
  running and standing waves at frequencies above 8 mHz are detected, with
  standing waves most evident in the highest atmospheric layers. Rough
  estimates based on a simplified model give height difference of about
  800 km between the sites of the Mg I 5173-A line and the Fe I 5383-A
  line and about 3150 km between the site of the Na D(1) line and the
  reflecting layer. It is inferred that the horizontal magnetic field
  in this region is too disperse or too weak to affect the short-period
  acoustic waves.

Title: Helioseismology: Oscillations as a Diagnostic of the Solar
    Interior
Authors: Deubner, Franz-Ludwig; Gough, Douglas
Bibcode: 1984ARA&A..22..593D
Altcode:
  Contents: (1) Introduction. (2) Resonant cavities in the
  Sun. (3) Observational methods. (4) High-degree modes: Solar
  structure. Subphotospheric velocities. (5) Low-degree modes: High-order
  p modes. Gravity modes. Solar structure. (6) Five-minute modes of
  intermediate degree. (7) Limb observations. (8) Problems for the
  immediate future. Appendix: Classification of stellar oscillations.

Title: Powerspectra of Short-Period Oscillations
Authors: Deubner, F. -L.
Bibcode: 1984ssdp.conf...14D
Altcode:
  As a result of the discussion of various hypotheses brought forward
  to explain the existence of persistent subsidiary peaks in the high
  frequency slope of the p-mode oscillations power spectra of the sun,
  the author finds that all of them appear inadequate to account for
  the properties of the spectra established so far.

Title: On the Phase Relations of High Degree p-Modes (Keynote Talk)
Authors: Deubner, F. -L.
Bibcode: 1984ssdp.conf....2D
Altcode:
  One of the long-standing problems in solar physics has been the
  interpretation of phase spectra of velocity and intensity fluctuations
  in the range of frequencies higher than about 5 mHz. Neither running
  nor standing waves have clearly and consistently been identified. In
  the last couple of years, however, considerable progress has been made
  in this field on which the author focuses his presentation.

Title: The detection limits in ground based measurements of stellar
    microvariability.
Authors: Deubner, F. -L.; Isserstedt, J.
Bibcode: 1983A&A...126..216D
Altcode:
  With photoelectric photometry in the VBLUW system the authors have
  tried to detect short period brightness fluctuations in solar-like
  stars. Although the result of this experiment is negative, the
  r.m.s. noise level per frequency band of ca. 2.5×10<SUP>-5</SUP> mag
  in the data appears low enough to encourage the ground-based search
  for low-1 p-mode oscillations in F-type main sequence stars.

Title: The influence of seeing on the observation of short period
    fluctuations in the solar atmosphere
Authors: Endler, F.; Deubner, F. -L.
Bibcode: 1983A&A...121..291E
Altcode:
  It is noted that the possibility exists for removing the effects of
  seeing on the phase spectra from simultaneous observations of velocity
  and intensity fluctuations in different photospheric and chromospheric
  spectral lines, since seeing events in simultaneous data sets appear at
  the same time with a preferred correlation. Image motion produces the
  preferential contamination of the data at those solar disk locations
  where solar signal spatial gradients are large. At periods larger than
  40 sec, the corrected power spectra and phase spectra generally show
  signals with significant coherence.

Title: Short-Period Oscillations
Authors: Deubner, F. -L.; Laufer, J.
Bibcode: 1983SoPh...82..151D
Altcode: 1983IAUCo..66..151D
  Short period oscillations (with periods less than 150 s) are shown to
  be non-uniformly distributed on the solar surface, and in time. Rather,
  they appear concentrated in short bursts which preferentially occur
  in regions with strong instantaneous downflow motion throughout the
  observed extent of the solar atmosphere.

Title: Phasenspektren von kurzperiodischen solaren Oszillationen
Authors: Deubner, F. -L.; Endler, F.
Bibcode: 1983MitAG..60..221D
Altcode:
  No abstract at ADS

Title: Helioseismology with High Degree P-Modes
Authors: Deubner, F. -L.
Bibcode: 1983SoPh...82..103D
Altcode: 1983IAUCo..66..103D
  The value of p-modes of high degree l as a diagnostic for the structure
  and dynamics of the solar envelope is reviewed.

Title: Spectral line transfer effects in Lambdameter measurements
    of solar short-period oscillations
Authors: Deubner, F. -L.; Durrant, C. J.; Kaltenbacher, J.
Bibcode: 1982A&A...114...85D
Altcode:
  Lambdameter records with different exit-slit settings yield power
  spectra of short period oscillations in the solar atmosphere, observed
  in the Na D(1) line and medium strong Fe I line, whose structure
  is notably stable with regard to slit geometry changes. By means of
  short period wavetrain numerical modeling, it is demonstrated that
  while such a structure in the power spectra of photospheric lines
  is absent for rms wave amplitudes lower than about 0.1 km/sec, it
  emerges with higher amplitudes as a consequence of nonlinearities in
  the line transfer process. It is emphasized that the nonlinear effect
  presently investigated must also be considered in stronger chromospheric
  lines. Linear correction factors cannot be applied to the observed power
  in order to deduce the energy flux carried by the acoustic waves if
  nonlinear effects are the only source of the observed spectral pattern.

Title: On the magnitude and the height dependence of the granular
    vertical flow velocity
Authors: Baessgen, M.; Deubner, F. -L.
Bibcode: 1982A&A...111L...1B
Altcode:
  Granular velocities determined from excellent quality solar spectra
  in two spectral lines are corrected for instrumental and atmospheric
  image degrading effects by the application of a modulation transfer
  function derived from the same material by comparing the observed
  brightness fluctuation spectra with various true spectra from
  the literature. k-omega spectra are used to separate granular and
  oscillatory fluctuations. The results favor a rather flat gradient
  with photospheric (C I 5380 line) rms granular velocities of at least
  1.0 km/sec

Title: Institut für Astronomie und Astrophysik, Lehrstuhl
    Astronomie. Jahresbericht für 1981.
Authors: Deubner, F. -L.
Bibcode: 1982MitAG..56..323D
Altcode:
  No abstract at ADS

Title: Pulsations and oscillations.
Authors: Deubner, F. L.
Bibcode: 1981NASSP.450...65D
Altcode: 1981suas.nasa...65D
  The observations of the oscillations of the solar atmosphere
  are a powerful diagnostic tool for research into the structure
  of the atmosphere from inside the convection zone to the upper
  chromosphere. Interpretations of the global pulsations or oscillations
  are presented with emphasis on using these observations to study the
  structure of the interior of the Sun.

Title: Solar granulation study in partial eclipse conditions using
    speckle interferometric techniques
Authors: Ricort, G.; Aime, C.; Deubner, F.; Mattig, W.
Bibcode: 1981A&A....97..114R
Altcode:
  During the partial eclipse of April 29, 1976, photoelectric
  speckle-interferometric measurements of solar granulation were obtained
  using the 35 cm domeless coudé refractor of the Kiepenheuer Institute,
  operated at the Anacapri Island observatory. <P />A radial cut of
  the two-dimensional power spectrum of the intensity distribution was
  calculated and the empirical modulation transfer function (M.T.F.),
  determined from the lunar limb profile, was used for correcting the
  data. This experimental M.T.F. which contains the combined effects
  of instrumental diffraction and atmospheric seeing is found to be
  in very good agreement with Korff's theoretical model computed for
  a Fried parameter r0 equal to 2.3 cm. <P />The corrected intensity
  fluctuation (ΔI)r.m.s.= 16.5% for λ=5300 A. The maximum power is
  found to be split into two components located respectively at 0.2 and
  0.4 cycles per arc second. The shape of the power spectrum confirms
  the fall in energy towards very low spatial frequencies, whereas the
  poor precision obtained in the high frequency range cannot permit an
  exponential decrease of the solar granulation power spectrum to be
  confirmed or refuted.

Title: Detection of low order p-modes in brightness fluctuations of
    the Sun
Authors: Deubner, F. -L.
Bibcode: 1981Natur.290..682D
Altcode:
  The discovery of radial and non-radial global oscillations of the Sun
  through various types of detector systems has opened the field of solar
  seismology. Of particular importance for studies of the deep interior of
  stars are the detection and analysis of low harmonic order pulsations
  such as the low order p-modes recently found on the Sun<SUP>1,2</SUP>
  by line shift measurements. These pulsations have now also been detected
  in the solar brightness fluctuations. Through the reflected light of
  Uranus and Neptune the Sun was observed as though it were a distant
  star. The positive results suggest that broad-band photometry has the
  greatest potential for developing seismometry of main sequence stars.

Title: Institut für Astronomie und Astrophysik, Lehrstuhl
    Astronomie. Jahresbericht für 1980.
Authors: Deubner, F. -L.
Bibcode: 1981MitAG..53..295D
Altcode:
  No abstract at ADS

Title: Das Innere der Sterne bloßlegen.
Authors: Deubner, F. -L.
Bibcode: 1981S&W....20....7D
Altcode:
  No abstract at ADS

Title: Global oscillations of the sun.
Authors: Deubner, F. -L.
Bibcode: 1980HiA.....5...75D
Altcode:
  A review is made of the progress achieved and the problems encountered
  over the past three years in studies of solar global oscillations
  and their interpretation with respect to the structure of the solar
  interior. Topics covered include disk observations, measurements at
  the limb, sources of signals other than global modes of oscillation,
  and the coherence of p-modes on the disk.

Title: Institut für Astronomie und Astrophysik, Lehrstuhl
    Astronomie. Jahresbericht für 1979.
Authors: Deubner, F. -L.
Bibcode: 1980MitAG..49..289D
Altcode:
  No abstract at ADS

Title: Observations of the hydrodynamic wave mode spectrum of the sun.
Authors: Deubner, F. -L.
Bibcode: 1980vasg.meet...A2D
Altcode: 1980vasg.meetQ....D
  The spectrum of periods of hydrodynamic oscillations and waves in
  the sun ranges from seconds to several hours. Although the p-mode
  character of the 5-min oscillation has been established, there is still
  considerable debate as to the significance and solar origin of signals
  observed in the outer ranges of the spectrum. Recent developments in
  studies of longer period oscillations observed at the solar limb or in
  the integrated light of the disk are discussed. Improved resolution
  and identification of low order solar p-modes has made it possible
  to perform radial differential rotation measurements. Fluctuations
  observed spectroscopically in the outer layers of the solar atmosphere
  are less regular, and their energy flux appears insufficient for upper
  chromospheric and coronal heating.

Title: On the center to limb variation of the granular brightness
    fluctuations.
Authors: Schmidt, W.; Deubner, F. -L.; Mattig, W.; Mehltretter, J. P.
Bibcode: 1979A&A....75..223S
Altcode:
  The center to limb variation of the granular brightness contrast
  was studied on the basis of slit-jaw photographs obtained with the
  balloon-borne Spektro-Stratoskop telescope, flown at an altitude of
  about 28 km on May 17, 1975 and during the partial solar eclipse of
  April 26, 1976 on Tenerife. Positions concentrate at cosine theta
  values of about 1, 0.6 and 0.2. The granular contrast was found to
  decrease monotonically towards the solar limb, with the magnitude of
  contrast about three times smaller at cosine theta 2 than at the disk
  center. The relative center to limb variation was found to be 10.4%
  (eclipse observations by a 40 cm evacuated Newtonian reflector at 422
  nm) and 8.6% (Spektro-Stratoskop observations at 556 nm). Discrepancies
  between these results and those reported by Deubner and Mattig (1975)
  are thought to be due to corrections for photographic noise and other
  factors.

Title: Solar p-mode oscillations as a tracer of radial differential
    rotation.
Authors: Deubner, F. -L.; Ulrich, R. K.; Rhodes, E. J., Jr.
Bibcode: 1979A&A....72..177D
Altcode:
  Photoelectric observations of solar p-modes obtained with improved
  wavenumber and frequency resolution are presented. The observations
  are compared with model calculations of the p-modes, and the degree
  of spatial and temporal coherence of the observed wave pattern is
  investigated. It is found that the p-mode oscillations pervade the
  visible surface of the sun with a high degree of coherence in space
  and time, so that the whole complex pattern of standing waves with
  its nodes and antinodes can be regarded as a fixed pattern corotating
  with the solar surface layers. The p-modes are introduced as a tracer
  of solar rotational flow velocities. The equatorial differential
  rotation is estimated as a function of effective depth on the basis
  of the theoretical contribution functions for the p-modes recently
  derived by Ulrich et al. (1978). The results strongly indicate that
  the angular speed of rotation is not uniform even in the relatively
  shallow layer extending about 20,000 km below the photosphere.

Title: A new technique for measuring solar rotation.
Authors: Rhodes, E. J., Jr.; Deubner, F. -L.; Ulrich, R. K.
Bibcode: 1979ApJ...227..629R
Altcode:
  A new technique for measuring solar photospheric and subphotospheric
  rotation rates is described. The technique utilizes the
  standing-wave nature of the nonradial p-mode oscillations of the
  whole sun. Specifically, the technique is based upon the observed
  concentration of p-mode oscillatory power into well defined ridges in
  two-dimensional wavenumber-frequency power spectra. The frequencies
  of the ridges in the eastward- and westward-traveling portions of an
  individual spectrum are systematically shifted in opposite directions
  by a drift of the standing-wave pattern across the observing field
  of view. The magnitudes of these frequency shifts are related to the
  drift velocity and to the horizontal wavenumber in such a way that
  measurement of the observed frequency shifts in a spectrum yields the
  drift velocity for that observing run. By guiding on the solar limbs
  and observing the velocity field at disk center, the observed drift
  velocity obtained in this way is exactly the rotational velocity of
  the solar p-mode pattern, and of the solar gas itself.

Title: The effect of a radial rotational velocity gradient on p-mode
    eigenfrequencies.
Authors: Ulrich, R. K.; Rhodes, E. J., Jr.; Deubner, F. -L.
Bibcode: 1979ApJ...227..638U
Altcode:
  The splitting of p-mode eigenfrequencies due to a depth-dependent solar
  rotation rate is considered. It is shown that to a first approximation
  this splitting can be treated as resulting from the translation of
  the wave pattern across the field of view with a velocity equal the
  actual velocity at a depth called the effective depth. The effective
  depths for a model solar envelope with l/H = 3 are presented as a
  function of position on the (kh, omega)-plane. The combination of
  omega near 0.025/s and kh near 0 yields the deepest probe of the solar
  envelope. For this same combination of kh and omega it is possible
  to resolve individual groups of eigenmodes in frequency but not in
  spatial wavenumber. Achievement of this resolution observationally
  may permit a determination of the lifetime of these particular modes.

Title: Die Mitte-Rand-Variation des granularen Intensitätskontrastes
Authors: Schmidt, W.; Deubner, F. L.; Mattig, W.; Mehltretter, J. P.
Bibcode: 1979MitAG..45..148S
Altcode:
  No abstract at ADS

Title: Velocity fields in the solar atmosphere /Observations/
Authors: Deubner, F. L.
Bibcode: 1977MmSAI..48..499D
Altcode:
  In the present paper, oscillatory and quasi-oscillatory motions observed
  in the photosphere and lower chromosphere are discussed along with
  convective motions on different horizontal scales. The discussion
  covers global oscillatory modes with predominantly radial harmonic
  motions and a coherent wave pattern across the entire solar surface,
  implying global excitation; oscillatory modes with large coherent wave
  systems, not necessarily globally excited (five minute oscillations);
  locally excited short period waves (excited by the Lighthill mechanism,
  no trapping, rapid dissipation); and nonoscillatory velocity (and
  brightness) fluctuations, related to convective motions.

Title: Is the Sun a Short Period Variable?
Authors: Deubner, F. -L.
Bibcode: 1977A&A....57..317D
Altcode:
  SUMMARY Variations of the solar diameter and fluctuations of
  the average surface velocity of the solar disc as observed by
  various authors suggest the existence of low amplitude global solar
  pulsations. Independent assessment of the order of magnitude and,
  maybe, of the reality of these effects was attempted, monitoring
  the solar luminosity by dual channel photometric observations of the
  planets Uranus and Neptune. on the basis of a power spectrum analysis we
  conclude that for periods shorter than 3 hours there is no luminosity
  fluctuation detectable with amplitudes larger than 6 lO- rms per
  independent frequency interval. Key wor : Solar global pulsations,
  Luminosity fluctuations

Title: INVITED PAPER - The Global Structure of the 5-min Oscillations
    and its Implication for Differential Rotation.
Authors: Deubner, F. -L.
Bibcode: 1977BAAS....9..374D
Altcode:
  No abstract at ADS

Title: The global structure of the 5-min oscillations and its
    implication for differential rotation.
Authors: Deubner, F. -L.
Bibcode: 1977BAAS....9..375D
Altcode:
  No abstract at ADS

Title: The small scale structure of solar magnetic fields. Joint
    discussion at the XVIth General Assembly of the I.A.U., Grenoble,
    1976.
Authors: Deubner, F. L.; Schmidt, H. U.
Bibcode: 1977HiA.....4B.219D
Altcode: 1977HiA.....4..219D
  No abstract at ADS

Title: Dynamics of the Solar Atmosphere. Review of Current
    Observational Investigations in the Visible
Authors: Deubner, F.
Bibcode: 1977ebhs.coll...45D
Altcode: 1977IAUCo..36...45D
  No abstract at ADS

Title: The small scale structure of solar magnetic fields. Joint
    discussion at the XVIth General Assembly of the I.A.U., Grenoble,
    1976.
Authors: Deubner, F. L.; Schmidt, H. U.
Bibcode: 1977ssss.conf.....D
Altcode:
  No abstract at ADS

Title: Solar p-Mode Oscillations as a Tracer of Large-Scale Horizontal
    Motions
Authors: Deubner, F. -L.
Bibcode: 1977lsms.proc...77D
Altcode:
  No abstract at ADS

Title: Observations of short period acoustic waves bearing on the
    interpretation of "microturbulence".
Authors: Deubner, F. -L.
Bibcode: 1976A&A....51..189D
Altcode:
  Observational material and methods of analysis used to investigate
  the detectability of short period waves in the solar atmosphere are
  reviewed. The chief evidence for the presence of an acoustical wave
  field is supplied by the power spectra of velocity fluctuations derived
  from high spatial resolution solar spectra. The striking feature of
  these spectra is that the kinetic power at higher frequencies does not
  decrease monotonically, but rather cascades over a series of nearly
  equidistant intermediate maxima and minima, which can be explained
  in terms of a homogeneous layer of finite thickness where the line
  contribution function is constant, but zero elsewhere. Calculations
  based on this model show that the resulting short-period waves can
  quantitatively account for the effects of nonthermal broadening.

Title: Photospheric magnetic flux concentrations and the granular
    velocity field.
Authors: Deubner, F. -L.
Bibcode: 1976A&A....47..475D
Altcode:
  The discovery that magnetic flux in the solar photosphere outside of
  sunspots occurs only in the form of highly concentrated flux elements
  of subgranular size with high maximum fields of the order of 1.5 kG has
  prompted a continuing discussion of how these fragile structures are
  being produced and protected against rapid diffusion and dissipation. In
  this context, an adequate quantitative picture of the photospheric
  (granular) velocity field is of crucial importance. In particular, high
  vertical velocities are required for models in which the magnetic-flux
  elements are kept in a nonstationary dynamical equilibrium configuration
  with reduced internal gas pressure by a pumping mechanism. It is of
  interest to review some recent observations which indicate that the
  granular velocities are locally much higher (as high as 6 km/s),
  than the values commonly assumed.

Title: Neue Beobachtungen zur Deutung der Mikroturbulenz
Authors: Deubner, F. L.
Bibcode: 1976MitAG..38..203D
Altcode:
  No abstract at ADS

Title: Observations of low wavenumber non radial eigenmodes of the sun
Authors: Deubner, F. L.; Mc Intyre
Bibcode: 1976pmas.conf..259D
Altcode:
  No abstract at ADS

Title: Spatially Resolved Observations of Solar Global Relations
Authors: Deubner, F. L.
Bibcode: 1976IAUTB..16..244D
Altcode: 1976IAUT...16B.244D
  No abstract at ADS

Title: Observations of short period acoustic waves bearing on the
    interpretation of "microturbulence"
Authors: Deubner, F. L.
Bibcode: 1976pmas.conf..263D
Altcode:
  No abstract at ADS

Title: New observations of the granular intensity fluctuations.
Authors: Deubner, F. L.; Mattig, W.
Bibcode: 1975A&A....45..167D
Altcode:
  White-light photographs of solar granulation obtained with a
  40-cm evacuated reflector during the partial eclipse of June 30,
  1973, are used for a statistical analysis of granular intensity
  fluctuations. Two-dimensional power spectra of the intensity
  distribution are calculated directly, and an instrument spread function
  derived from photometric scans across the lunar limb is employed for
  correcting the data. The mean FWHM of the spread function corresponded
  to 0.52 sec. The corrected RMS intensity fluctuation is found to be
  0.128 for a wavelength of 607 nm, and maximum power is found to occur
  at the wave number corresponding to a wavelength of 1340 km or 1.85 sec.

Title: La estructura fina de la rotación diferencial solar.
Authors: Deubner, F. -L.; Vázquez, M.
Bibcode: 1975UrBar..60...39D
Altcode:
  No abstract at ADS

Title: Observations of low wavenumber nonradial eigenmodes of the sun.
Authors: Deubner, F. -L.
Bibcode: 1975A&A....44..371D
Altcode:
  Photoelectric observations of the photospheric velocity field with high
  resolution in horizontal wavenumber and frequency have been carried
  out in the C I 5380-A line. Three or four discrete stable modes of
  the five-minute oscillations are resolved in the wavenumber-frequency
  diagram, which agree in many respects with the predicted fundamental
  modes of subphotospheric standing acoustic waves. Some interesting
  aspects of the confirmation of a 'global' excitation mechanism of the
  five-minute oscillations are pointed out. Several apparently discordant
  details of previous observations are rediscussed, and it is shown that
  they can be reconciled with the present results.

Title: Differential Rotation and the Spot Zones
Authors: Deubner, F. -L.; Vazquez, M.
Bibcode: 1975SoPh...43...87D
Altcode:
  A minimum of angular velocity is not found at the equator as suggested
  by Gilman, but at a latitude of 6° in both hemispheres.

Title: Acoustic Waves and the Geometric Scale in the Solar Atmosphere
Authors: Deubner, F. -L.
Bibcode: 1975SoPh...40..333D
Altcode:
  It is shown that the phase and group velocity of fluctuations in
  different solar spectral lines are equal in the high-frequency
  fluctuation tail where sound waves propagate. The motion of a
  disturbance is described, the characteristics of which agree with those
  of an acoustic wavefront traveling upward with gradually increasing
  amplitude, and the frequency and velocity of the disturbance are plotted
  as functions of time. Relative heights are found for regions where C I,
  Fe I, Na I, and H-alpha lines form, and the results are shown to agree
  with previous theoretical estimates.

Title: Photospheric and Chromospheric Magnetic Structures
Authors: Deubner, F. L.
Bibcode: 1975cesra...5...39D
Altcode:
  No abstract at ADS

Title: Photospheric and chromospheric magnetic structures.
Authors: Deubner, F. L.
Bibcode: 1975MmArc.105...39D
Altcode:
  No abstract at ADS

Title: Die Intensitätsfluktuation der Granulation
Authors: Deubner, F. L.; Mattig, W.
Bibcode: 1975MitAG..36..148D
Altcode:
  No abstract at ADS

Title: Photospheric and chromospheric magnetic structures
Authors: Deubner, F. L.
Bibcode: 1975esm..meet...39D
Altcode:
  Observations of the fine structure of the photospheric magnetic
  field and its chromospheric extension are reviewed, and some models
  of the flux concentrations and possible mechanisms for forming and
  maintaining this structure are considered. Chromospheric structures
  that are potentially of importance for constructing realistic models of
  solar magnetic structures are described, including the facular network,
  mottles, spicules, and filigrees. Photospheric structures described
  include magnetic knots and anomalous granulation. Difficulties in the
  interpretation of magnetic-field observations are discussed. Theoretical
  models of the surface magnetic flux are examined, and it is shown
  that turbulent pumping and the Bernoulli effect can be considered as
  possible mechanisms for concentrating or confining magnetic flux in flux
  ropes. Noting that the initial development of a magnetic configuration
  driven by supergranular convection leads to a funnel-shape geometry
  opening upwards, it is shown that such a configuration can be maintained
  in the presence of a force-free field, a temperature variation, or a
  dynamic effect.

Title: Acoustic waves and the Geometric scale in the Solar atmosphere
Authors: Deubner, F. L.
Bibcode: 1975MitAG..36..149D
Altcode:
  No abstract at ADS

Title: Some Properties of Velocity Fields in the Solar Photosphere. V:
    Spatio-Temporal Analysis of High Resolution Spectra
Authors: Deubner, F. -L.
Bibcode: 1974SoPh...39...31D
Altcode:
  Series of high resolution spectrograms taken simultaneously in three
  spectral regions were recorded with a lambda meter and subjected
  to a statistical analysis of the fluctuations of Doppler shift and
  brightness. The 5-min oscillations are confirmed to be `evanescent'
  waves. Their horizontal wavelengths range from 9″ to 15″ and
  probably still larger values.

Title: On the Energy Distribution in Wavenumber Spectra of the
    Granular Velocity Field
Authors: Deubner, Franz-Ludwig
Bibcode: 1974SoPh...36..299D
Altcode:
  Wavenummer spectra of spatial velocity fluctuations measured in selected
  high resolution solar photospheric spectrograms are presented. The
  statistical stability of the power estimates of particular `peaks'
  in these spectra is discussed.

Title: Hα Fine Structure and the Dynamics of the Solar Atmosphere
Authors: Deubner, F. -L.
Bibcode: 1974IAUS...56..263D
Altcode:
  No abstract at ADS

Title: Eine Prozeßrechner im Dienste der Sonnenphysik. Moderne
    Datenerfassung beim Fraunhofer Institut in Anacapri.
Authors: Deubner, F. -L.
Bibcode: 1974S&W....13...47D
Altcode:
  No abstract at ADS

Title: Is There Horizontal Phase Propagation of 5-min Oscillations
    at High Velocities?
Authors: Deubner, Franz-Ludwig; Hayashi, Nobukazu
Bibcode: 1973SoPh...30...39D
Altcode:
  New observations of the photospheric 5-min oscillations are presented
  which prove that the physical reality of the very high horizontal phase
  propagation velocities observed in connection with the oscillations
  cannot be maintained. Instead, a statistical model is proposed to
  explain the observed phase relations.

Title: Eine statistische Deutung der horizontalen
    Phasengeschwindigkeit der 5-Min.-Oszillationen
Authors: Deubner, F. -L.
Bibcode: 1973MitAG..32..182D
Altcode:
  No abstract at ADS

Title: On the Powerspectrum of the Photospheric Resonance Oscillations
Authors: Deubner, Franz-Ludwig
Bibcode: 1972SoPh...23..304D
Altcode:
  No abstract at ADS

Title: Some Properties of Velocity Fields in the Solar
Photosphere. IV: Long Periods, Five Minute Oscillations, and the
    Supergranulation at Lower Layers
Authors: Deubner, Franz-Ludwig
Bibcode: 1972SoPh...22..263D
Altcode:
  Photoelectric measurements of photospheric velocity fields have been
  carried out with the Sacramento Peak Doppler Zeeman Analyzer. Emphasis
  was given to long periods and low spatial wavenumbers in deep
  photospheric layers, where the 5-min oscillations are less dominant.

Title: Some Properties of Velocity Fields in the Solar
Photosphere. III: Oscillatory and Supergranular Motions as a Function
    of Height
Authors: Deubner, Franz-Ludwig
Bibcode: 1971SoPh...17....6D
Altcode:
  Photoelectric measurements of Doppler shifts of various Fraunhofer
  lines obtained with the Capri magnetograph were analysed. The height
  dependence of the supergranular and oscillatory motions, as well as
  the two dimensional structure of these velocity fields is investigated.

Title: Photoelectric Measurements of Sunspot Magnetic Fields
Authors: Deubner, F. -L.; Göhring, R.
Bibcode: 1971IAUS...43..190D
Altcode:
  No abstract at ADS

Title: Photoelectric Polarimetry of a Dark Unipolar Sunspot
Authors: Deubner, F. -L.; Göhring, R.
Bibcode: 1970SoPh...13..118D
Altcode:
  Photoelectric polarisation measurements in a stable sunspot (type H)
  with a particularly dark umbra carried out with the Capri magnetograph
  have been evaluated in terms of Unno's (1956) theory to give the
  value and direction of the magnetic field vector. A linear increase of
  the inclination angle with distance from the spot centre up tor ≈
  1.2R<SUB>s</SUB> results, as originally found by Hale and Nicholson
  (1938) with a different procedure. The field strength decreases from
  the maximum value (about 3300Γ) to about 15% at the penumbral border,
  still continuously decreasing outside the spot. The projected field
  direction deviates considerably from the radial symmetry in several
  parts of the spot region, but it is in good agreement with that of
  the overlaying chromospheric structures.

Title: Die unruhige Oberfläche der ruhigen Sonne.
Authors: Deubner, F. -L.
Bibcode: 1970S&W.....9..285D
Altcode:
  No abstract at ADS

Title: Some Properties of Velocity Fields in the Solar
Photosphere. II: The Spatial Distribution of the Oscillatory Field
Authors: Deubner, Franz-Ludwig
Bibcode: 1969SoPh....9..343D
Altcode:
  No abstract at ADS

Title: The Vectormagnetograph of the Fraunhofer Institut
Authors: Deubner, Franz-Ludwig; Liedler, R.
Bibcode: 1969SoPh....7...87D
Altcode:
  A new vectormagnetograph is described that measures all components of
  the magnetic field vector strictly simultaneously. The azimuth of the
  direction of the field is continuously obtained during the observation
  by means of a servo circuit. As a first step of data recording
  a photographic method is applied which presents all 5 quantities
  (longitudinal and transverse component of the field vector, azimuth,
  Doppler shift and intensity) in the form of maps.

Title: Photoelektrische Magnetfeldmessungen an einem regulären
    Sonnenfleck mit besonders dunkler Umbra
Authors: Deubner, F. -L.; Göhring, R.
Bibcode: 1969MitAG..27..205D
Altcode:
  No abstract at ADS

Title: Photoelektrische Registrierungen des photosphärischen
    Netzwerks
Authors: Deubner, F. -L.
Bibcode: 1969MitAG..27..204D
Altcode:
  No abstract at ADS

Title: On the Influence of Seeing on Photospheric Velocity
    Measurements
Authors: Deubner, Franz Ludwig
Bibcode: 1968SoPh....3..439D
Altcode:
  It is shown that the short-period fluctuations of photospheric velocity
  records can be explained by the scanning effect of atmospheric seeing
  (image motion) and the velocity gradients present on the solar
  surface. Some observations supporting this explanation are presented.

Title: Magnetic and Doppler Oscillations in Active Regions
Authors: Deubner, F. L.
Bibcode: 1968IAUS...35..230D
Altcode:
  No abstract at ADS

Title: Über die Vertikalkomponente der Supergranulationsströmung
Authors: Deubner, F. L.
Bibcode: 1968MitAG..25..188D
Altcode:
  No abstract at ADS

Title: Some Properties of Velocity Fields in the Solar Photosphere
Authors: Deubner, Franz Ludwig
Bibcode: 1967SoPh....2..133D
Altcode:
  Photoelectric records of the Doppler effect (DE) and longitudinal
  Zeeman effect (LZE) were obtained with the Capri magnetograph of the
  Fraunhofer Institut photoelectric, using the FeI line λ 5250.22. Each
  record consists of 65 scans repeated along the same line on the sun. The
  analysis of 16 records covering a total of 485 oscillating regions
  (period 300 sec) leads to the following results: The mean lifetime of
  the DE-oscillations outside active regions is 20 min and 32 min in the
  neighborhood of spotgroups. Discarding the weakest sporadic osculations,
  one obtains 27 min and 43 min respectively. The most frequent lifetime
  in both cases is 15 min.

Title: On the reorganization of field lines during a flare
Authors: Deubner, F. L.
Bibcode: 1965IAUS...22..369D
Altcode:
  No abstract at ADS

Title: Eine Beobachtung zum Problem der Koinzidenz von Eruptionen
    und magnetischen Neutrallinien. Mit 2 Textabbildungen
Authors: Deubner, F. L.
Bibcode: 1962ZA.....55..123D
Altcode:
  No abstract at ADS

Title: Über die Anwendung weiter Spektrographenspalte
    beilichtelektrischen Polarisationsmessungen an Fraunhoferlinien. Mit
    4 Textabbildungen
Authors: Deubner, F. L.
Bibcode: 1962ZA.....56....1D
Altcode:
  No abstract at ADS

Title: Der Magnetograph des Fraunhofer Instituts. Mit 5
    Textabbildungen
Authors: Deubner, F. L.; Kiepenheuer, K. O.; Liedler, R.
Bibcode: 1961ZA.....52..118D
Altcode:
  No abstract at ADS

Title: Über die Verminderung des Streulichts in
    Abbildungs-systemen. Mit 4 Textabbildungen
Authors: Deubner, F. -L.
Bibcode: 1959ZA.....48...34D
Altcode:
  No abstract at ADS

Title: Zur lichtelektrischen Registrierung und Photometrie von
    Fackeln und Eruptionen. Mit 6 Textabbildungen
Authors: Kiepenheuer, K. O.; Deubner, F. L.
Bibcode: 1958ZA.....45...17K
Altcode:
  No abstract at ADS

