Author name code: kostik
ADS astronomy entries on 2022-09-14
author:"Kostik, Roman I." OR author:"Kostyk, Roman I." 
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Title: Results of observations of wave motions in the Solar facula
Authors: Shchukina, N. G.; Kostyk, R. I.
Bibcode: 2022KFNT...38...71S
Altcode:
  No abstract at ADS

Title: Solar Faculae: Microturbulence as an Indicator of Inclined
    Magnetic Fields
Authors: Stodilka, M. I.; Kostyk, R. I.
Bibcode: 2020KPCB...36..153S
Altcode:
  The observations of the solar facula in the Ba II λ 455.403
  Å line are used to construct a 3D model of the facula area by
  solving the inverse nonequilibrium radiative transfer problem and to
  investigate the fine structure of the field of unresolved velocities
  (microturbulence). New turbulent structures are formed in the layers
  of the upper photosphere. They are localized mainly between upward
  and downward flows with the formation of ring-shaped structures of
  increased turbulence around these flows. The mechanism of magnetic
  anisotropy of microturbulent velocity is proposed (small-scale eddy-type
  plasma motions mainly occur in the planes perpendicular to the magnetic
  field), which explains the height dependence of the field of unresolved
  velocities. Anisotropy of microturbulence begins to manifest itself in
  the lower photospheric layers outside the upward and downward flows,
  while it manifests itself in the higher layers inside these flows. The
  increase of microturbulence in the layers of the upper photosphere and
  the lower chromosphere in the areas between matter flows indicates the
  presence of inclined magnetic fields, which, along with the blurring
  of its spatial structure, indicates the existence of a magnetic
  canopy region. Microturbulence can be used as an additional tool for
  diagnostics of inclined magnetic fields.

Title: Solar faculae: microturbulence as an indicator of inclined
    magnetic fields
Authors: Stodilka, M. I.; Kostyk, R. I.
Bibcode: 2020KFNT...36d...3S
Altcode:
  No abstract at ADS

Title: Velocity Field Diagnostics of the Quiet Sun Using the
Lambda-Meter Method: Si I 1082.7 nm Line
Authors: Shchukina, N. G.; Kostyk, R. I.
Bibcode: 2020KPCB...36....1S
Altcode:
  The validity of the lambda-meter method for determining the quiet
  Sun velocity field using the Si I 1082.7 nm line is investigated. To
  this end, the intensity profiles of this line were calculated for the
  solar disk center by means of NLTE simulations in a three-dimensional
  model atmosphere describing the small-scale magnetic activity in
  the quiet solar photosphere. The velocity field recovered using
  the lambda-meter method from theoretical NLTE profiles of the Si I
  1082.7 nm line was compared with the velocity field from the model
  atmosphere. The influence of atmospheric and instrumental effects on
  the results is considered. These effects are atmospheric turbulence
  and light diffraction by telescope aperture, such as VTT, GREGOR,
  and EST/DKIST. It is shown that, in the case of observations of
  the Si I 1082.7 nm line on large-diameter telescopes like GREGOR and
  EST/DKIST with a spatial resolution substantially better than 0.27″,
  the lambda-meter method provides reliable values of the velocity field
  for the lower and upper solar photosphere. For the middle photosphere,
  the correlation between the inferred and the real velocities is
  worse, particularly when using the smaller diameter telescopes like
  VTT. Under a poor spatial resolution exceeding 2″, information about
  the velocity field can be obtained only for the uppermost photospheric
  layers. For this case, the lambda-meter velocities turn out to be
  noticeably smaller than the real values.

Title: Long-term monitoring of spectral line variations with the
    11-year cycle. Quiet Sun.
Authors: Osipov, S. N.; Shchukina, N. G.; Kostyk, R. I.; Stodilka,
   M. I.
Bibcode: 2020A&AT...31..465O
Altcode:
  The monitoring program of long-term variation of selected solar
  spectral lines is described. The aim of the program is to study
  how the physical parameters of the quiet solar atmosphere change
  over the last solar cycle 24. The research is based on high spectral
  resolution observations of the quiet Sun using the Ernest Gurtovenko
  horizontal solar telescope of the Main Astronomical Observatory of the
  National Academy of Sciences of Ukraine. Since 2012 the observations
  are performed daily, when the weather conditions allow. We found that
  the line core depths and full widths at half maximum of the Fe I solar
  spectral lines correlate with the cycle modulation of the total unsigned
  magnetic field and the Wolf numbers of the Sun. The behaviour of these
  line parameters can be explained by variations of the temperature of
  the quiet photosphere during the 11-year cycle.

Title: Diagnostics of the velocity field of the quiet Sun using the
lambda-meter method: The Si I 1082.7 nm line
Authors: Shchukina, N. G.; Kostyk, R. I.
Bibcode: 2020KFNT...36a...3S
Altcode: 2020KFNT...36....3S
  No abstract at ADS

Title: Features of Convection in the Atmospheric Layers of the
    Solar Facula
Authors: Stodilka, M. I.; Prysiazhnyi, A. I.; Kostyk, R. I.
Bibcode: 2019KPCB...35..261S
Altcode:
  According to the data of complex 2D observations on the VTT telescope
  of the solar facula, a 3D model of the solar atmosphere in the facular
  region was obtained by solving the inverse radiative transfer problem
  in the Ba II 4554 A line. The magnetic field was estimated using the
  Stokes V profiles of the Fe I 15648 A line. The influence of magnetic
  field on photospheric convection was investigated: spatial variations
  in temperature and velocities at different heights were considered. It
  is shown that the mutual transformation of the mechanical and thermal
  energy of the solar plasma into magnetic energy occurs in the layers of
  the middle photosphere. The integral effect of a small-scale magnetic
  dynamo leads to lowering the temperature and slowing down the motion of
  the predominant downward flows in the layers of the middle photosphere
  in the facular regions with a strong field (greater than 1 kG),
  while there is an increase in temperature and acceleration of the
  motion of the predominant upward flows in the layers of the middle
  photosphere in the facular regions with a weak field (less than 1
  kG). It is shown that the magnetic field of the facula stabilizes
  photospheric convection, and the small-scale magnetic dynamo causes
  a double temperature inversion in the photospheric layers of the facula.

Title: Features of convection in the atmosphere layers of the
    solar facula
Authors: Stodilka, M. I.; Prysiazhnyi, A. I.; Kostyk, R. I.
Bibcode: 2019KFNT...35f..18S
Altcode:
  No abstract at ADS

Title: Effect of wave motions in the active region of the solar
    surface on convection
Authors: Kostik, R. I.
Bibcode: 2018KFNT...34b..46K
Altcode:
  No abstract at ADS

Title: Effect of Wave Motions in the Active Region of the Solar
    Surface on Convection
Authors: Kostyk, R. I.
Bibcode: 2018KPCB...34...82K
Altcode:
  The results of the observations of the active region (facula) near the
  center of the solar disk obtained with the German Vacuum Tower Telescope
  (VTT; Tenerife, Spain), are discussed. We have determined that the
  decrease in the contrast (brightness) of the facula with the magnetic
  field increasing from 130 to 160 mT is due to the fact that the V_V
  phase shift of waves in this range of magnetic field densities is close
  to zero (Φ VV ≍ 0), i.e., the wave becomes stationary and does not
  transfer energy from the photosphere to the chromosphere. The sound
  waves that propagate from the chromosphere towards the photosphere
  significantly affect the temperature characteristics of turbulent
  vortices at the level of formation of the continuous spectrum. In
  particular, the contrast of granules under the influence of these
  waves can increase by 25%.

Title: Kyiv monitoring program of spectral line variations with the
    11-year cycle
Authors: Shchukina, Nataliia; Osipov, Sergej; Kostyk, Roman; Stodilka,
   Myroslav
Bibcode: 2018IAUS..340...31S
Altcode:
  Kyiv program of monitoring of long-term variation of solar spectral
  lines at the horizontal solar telescope of the Main Astronomical
  Observatory of Ukraine is described. The aim of the program is to
  clarify the issue how the physical parameters of the quiet solar
  atmosphere change over the 11-year cycle of solar activity. The
  diagnostics of the atmospheric variation includes analysis of more than
  40 spectral lines of neutral and ionized chemical elements observed
  at the solar disk and at the limb near north and south poles with
  high spectral resolution. The results of monitoring show that during
  2012-2017 a line core depths and a line full widths at half maximum
  respond to the cycle modulation of the global unsigned magnetic
  field of the Sun. Such a correlation can be explained by assuming
  that temperature gradient of the solar photosphere is growing with
  solar activity.

Title: Kyiv monitoring program of fraunhofer lines variation with
    11-year cycle of solar activity
Authors: Osipov, Sergii; Kostik, Roman; Shchukina, Nataliia
Bibcode: 2017JPhSt..21.1901O
Altcode:
  The monitoring program of long-term variation of selected Fraunhofer
  lines is described. The aim of the program is to study how the physical
  parameters of the quiet solar atmosphere change over the solar cycle
  No. 24. The research is based on high spectral resolution observations
  of the quiet Sun using the horizontal solar telescope ATSU-5 of the
  Main Astronomical Observatory of the National Academy of Sciences of
  Ukraine. The diagnostics of the solar cycle atmospheric variation
  includes observations of the H alpha, Ca II K&amp;H and about 40
  spectral lines of neutral and ionized chemical elements at different
  positions on the solar disk. Since 2012 the observations are performed
  daily, when the weather conditions allow. The observational season
  lasts from March to October. The first results of the observations show
  that the line core depths and full widths at half maximum of the weak
  Fe I 538.634 nm, moderate Fe I 539.829 nm, and strong Fe I 558.677 nm
  lines, as well as the bisector curvature of the last two lines show
  response to the cycle modulation of the total unsigned magnetic field
  of the Sun. The behavior of these line parameters can be explained
  by variations of the temperature and convective motions of the quiet
  photosphere during this cycle.

Title: Monitoring program of selected Fraunhofer lines over the
    11-year cycle of solar activity
Authors: Osipov, S.; Kostik, R.; Shchukina, N.
Bibcode: 2017psio.confE.109O
Altcode:
  No abstract at ADS

Title: Two Spectra of Turbulence of the Sun
Authors: Kostik, R.; Kozak, L.; Cheremnykh, O.
Bibcode: 2017psio.confE.108K
Altcode:
  No abstract at ADS

Title: The possible origin of facular brightness in the solar
    atmosphere
Authors: Kostik, R.; Khomenko, E.
Bibcode: 2016A&A...589A...6K
Altcode: 2016arXiv160203369K
  This paper studies the dependence of the Ca II H line core brightness
  on the strength and inclination of the photospheric magnetic field, and
  on the parameters of convective and wave motions in a facular region
  at the center of the solar disc. We use three simultaneous data sets
  that were obtained at the German Vacuum Tower Telescope (Observatorio
  del Teide, Tenerife): (1) spectra of Ba II 4554 Å line, registered
  with the instrument TESOS to measure the variations of intensity
  and velocity through the photosphere up to the temperature minimum;
  (2) spectropolarimetric data in Fe I 1.56 μm lines (registered with
  the instrument TIP II) to measure photospheric magnetic fields;
  (3) filtergrams in Ca II H that give information about brightness
  fluctuations in the chromosphere. The results show that the Ca II H
  brightness in the facula strongly depends on the power of waves with
  periods in the 5-min range, which propagate upwards, and also on the
  phase shift between velocity oscillations at the bottom photosphere
  and around the temperature minimum height that is measured from Ba
  II line. The Ca II H brightness is maximum at locations where the
  phase shift between temperature and velocity oscillations lies within
  0°-100°. There is an indirect influence of convective motions on the
  Ca II H brightness. The higher the amplitude of convective velocities
  is and the greater the height is where they change their direction
  of motion, the brighter the facula. In summary, our results lead
  to conclusions that facular regions appear bright not only because
  of the Wilson depression in magnetic structures, but also owing to
  real heating.

Title: What mechanisms allow 5-minute oscillations in active regions
    of the solar surface to penetrate from the photosphere into the
    chromosphere?
Authors: Kostyk, R. I.
Bibcode: 2015KPCB...31..188K
Altcode:
  No abstract at ADS

Title: Periodic variations of the H α profile width in the
    chromosphere of coronal holes as a possible indicator of Alfvén waves
Authors: Zubkova, A. V.; Kobanov, N. I.; Sklyar, A. A.; Kostyk, R. I.;
   Shchukina, N. G.
Bibcode: 2014AstL...40..222Z
Altcode:
  We analyze the oscillations of the H α profile width based on our
  observations of the chromosphere at the base of solar coronal holes. The
  maximum oscillation amplitude averaged over ten time series is 64 m 0
  A. Direct calculations show that this value cannot be reached through
  temperature oscillations, because the periodic intensity fluctuations
  observed during our experiment did not exceed 5%, corresponding to H α
  profile broadening only by 1.5-2 m Å. We hypothesize that the observed
  variations can result from the propagation of torsional Alfvén waves
  in the chromosphere of coronal holes.

Title: Influence of magnetic field on propagation of five-minute
oscillations in the sun's atmosphere: Phase shifts
Authors: Kostik, R. I.; Shchukina, N. G.; Kobanov, N. I.; Pulyaev,
   V. A.
Bibcode: 2014KPCB...30...40K
Altcode:
  No abstract at ADS

Title: Properties of oscillatory motions in a facular region
Authors: Kostik, R.; Khomenko, E.
Bibcode: 2013A&A...559A.107K
Altcode: 2013arXiv1310.0184K
  <BR /> Aims: We study the properties of waves in a facular region of
  moderate strength in the photosphere and chromosphere. Our aim is to
  statistically analyse the wave periods, power, and phase relations
  as a function of the magnetic field strength and inclination. <BR />
  Methods: Our work is based on observations obtained at the German Vacuum
  Tower Telescope (Observatorio del Teide, Tenerife) using two different
  instruments: the Triple Etalon SOlar Spectrometer (TESOS) in the Ba
  ii 4554 Å line to measure velocity and intensity variations through
  the photosphere and, simultaneously, the Tenerife Infrared Polarimeter
  (TIP-II), in the Fe i 1.56 μm lines to measure the Stokes parameters
  and magnetic field strength in the lower photosphere. Additionally,
  we use the simultaneous broad-band filtergrams in the Ca ii H line to
  obtain information about intensity oscillations in the chromosphere. <BR
  /> Results: We find several clear trends in the oscillation behaviour:
  (i) the period of oscillation increases by 15-20% with the magnetic
  field increasing from 500 to 1500 G. (ii) The temperature-velocity
  phase shifts show a strikingly different distribution in the facular
  region compared to the quiet region, a significant number of cases
  in the range from - 180° to 180° is detected in the facula. (iii)
  The most powerful chromospheric Ca ii H intensity oscillations are
  observed at locations with strong magnetic fields (1.3-1.5 kG) inclined
  by 10-12 degrees, as a result of upward propagating waves with rather
  low phase speeds, and temperature-velocity phase shifts between 0°
  and 90°. (iv) The power of the photospheric velocity oscillations
  from the Ba ii line increases linearly with decreasing magnetic field
  inclination, reaching its maximum at strong field locations.

Title: Two spectra of turbulence of the sun
Authors: Kozak, L. V.; Kostyk, R. I.; Cheremnykh, O. K.
Bibcode: 2013KPCB...29...66K
Altcode:
  No abstract at ADS

Title: What are solar faculae?
Authors: Kostyk, R. I.
Bibcode: 2013KPCB...29...32K
Altcode:
  No abstract at ADS

Title: Different Modes of Turbulence in the Active Regions of the
    Solar Photosphere
Authors: Kozak, L. V.; Kostik, R. I.; Cheremnykh, O. K.
Bibcode: 2013OAP....26..271K
Altcode:
  In work the range of different methods for the analysis of
  characteristics of turbulent processes in the active regions of
  the solar photosphere has been used. The changes of fluctuations
  distribution function and its moments were analyzed, spectral
  analysis was carried out.It was found out from the observations of
  active region carried out with the 70-cm vacuum tower telescope VTT
  in Isanie (Tenerife Island, Spain) that the turbulent processes in
  the sun photosphere are characterized by two different spectra of
  turbulence. The first one of them is well known Kolmohorov spectrum,
  which describes the plasma with zero mean magnetic field. The second
  one is the Kraichnan spectrum with a different from zero mean magnetic
  field. Transition from one spectrum type to another one occurs at
  scale of 3 Mm.We have to note that the scale 3 Mm corresponds to one
  of mesogranulation and testifies about non-zero mean magnetic fields
  for the consideration of regions exceeding the granulation in active
  regions of the photosphere. Besides, this clears the possibility of
  appearance of selforganizing magnetic plasma structures such as spots,
  active regions and complexes of activity.

Title: Properties of convective motions in facular regions
Authors: Kostik, R.; Khomenko, E. V.
Bibcode: 2012A&A...545A..22K
Altcode: 2012arXiv1207.4340K
  <BR /> Aims: We study the properties of solar granulation in a facular
  region from the photosphere up to the lower chromosphere. Our aim is
  to investigate the dependence of granular structure on magnetic field
  strength. <BR /> Methods: We used observations obtained at the German
  Vacuum Tower Telescope (Observatorio del Teide, Tenerife) using two
  different instruments: the Triple Etalon SOlar Spectrometer (TESOS)
  to measure velocity and intensity variations along the photosphere in
  the Ba ii 4554 Å line; and, simultaneously, the Tenerife Infrared
  Polarimeter (TIP-II) to the measure Stokes parameters and the
  magnetic field strength at the lower photosphere in the Fe i 1.56
  μm lines. <BR /> Results: We find that the convective velocities of
  granules in the facular area decrease with magnetic field while the
  convective velocities of intergranular lanes increase with the field
  strength. Similar to the quiet areas, there is a contrast and velocity
  sign reversal taking place in the middle photosphere. The reversal
  heights depend on the magnetic field strength and are, on average,
  about 100 km higher than in the quiet regions. The correlation between
  convective velocity and intensity decreases with magnetic field at
  the bottom photosphere, but increases in the upper photosphere. The
  contrast of intergranular lanes observed close to the disk center is
  almost independent of the magnetic field strength. <BR /> Conclusions:
  The strong magnetic field of the facular area seems to stabilize the
  convection and to promote more effective energy transfer in the upper
  layers of the solar atmosphere, since the convective elements reach
  greater heights.

Title: Magnetic field effect on the fine structure of convective
    motions in the solar atmosphere
Authors: Kostyk, R. I.
Bibcode: 2012KPCB...28..155K
Altcode:
  No abstract at ADS

Title: Some properties of convective motions in the upper solar
    atmosphere. II
Authors: Kostyk, R. I.
Bibcode: 2011KPCB...27..175K
Altcode:
  No abstract at ADS

Title: Peculiarities of convective motions in the upper solar
    atmosphere. I
Authors: Kostyk, R. I.
Bibcode: 2010KPCB...26..233K
Altcode:
  No abstract at ADS

Title: Solar granulation from photosphere to low chromosphere observed
    in Ba II 4554 Å line
Authors: Kostik, R.; Khomenko, E.; Shchukina, N.
Bibcode: 2009A&A...506.1405K
Altcode: 2009arXiv0909.1210K
  Aims: The purpose of this paper is to characterize the statistical
  properties of solar granulation in the photosphere and low chromosphere
  up to 650 km. <BR />Methods: We use velocity and intensity variations
  obtained at different atmospheric heights from observations in Ba II
  4554 Å. The observations were done during good seeing conditions at
  the VTT at the Observatorio del Teide on Tenerife. The line core forms
  rather high in the atmosphere and allows granulation properties to
  be studied at heights that have been not accessed before in similar
  studies. In addition, we analyze the synthetic profiles of the Ba II
  4554 Å line by the same method computed taking NLTE effects into
  account in the 3D hydrodynamical model atmosphere. <BR />Results:
  We suggest a 16-column model of solar granulation depending on the
  direction of motion and on the intensity contrast measured in the
  continuum and in the uppermost layer. We calculate the heights of
  intensity contrast sign reversal and velocity sign reversal. We show
  that both parameters depend strongly on the granulation velocity and
  intensity at the bottom photosphere. The larger the two parameters,
  the higher the reversal takes place in the atmosphere. On average, this
  happens at about 200-300 km. We suggest that this number also depends
  on the line depth of the spectral line used in observations. Despite
  the intensity and velocity reversal, about 40% of the column structure
  of granulation is preserved up to heights around 650 km.

Title: Observations of a bright plume in solar granulation
Authors: Kostik, R. I.; Khomenko, E. V.
Bibcode: 2007A&A...476..341K
Altcode:
  Aims:The aim of this paper is to analyze the thermal properties,
  oscillatory, and flow motions of a bright, long-lasting feature
  observed in solar granulation, which we call the plume. <BR />Methods:
  We used the spectral observations of quiet granulation at solar disc
  center, including the two Fe II 5234 and Fe I 6393 Å lines recorded
  simultaneously at the German Vacuum Tower telescope in Tenerife. The
  recorded data revealed a stable, bright structure of 3-4 arcsec size
  present during the whole 2.5 h of observations. We compare the velocity
  fields extracted by means of a λ-meter method and temperature and
  pressure stratification obtained after inversion of the profiles related
  to granules, intergranular lanes, and the plume. <BR />Results: The
  following results were obtained: (i) the correlation between variations
  in convective velocity and intensity in the plume is close to zero
  at all observed heights; (ii) the velocity flow in the plume changes
  from a downflow in the deep layers to an upflow in the upper layers;
  (iii) the brightness of the plume increases with height; (iv) the
  amplitudes of the five-minute oscillations of intensity and velocity
  are twice lower in the plume than outside, and vertically propagating
  waves are observed; (v) the plume is hotter and denser than the quiet
  Sun in the upper photosphere. <BR />Conclusions: We conclude that the
  observed phenomenon has a non-convective origin. The decrease in the
  amplitudes of oscillations in the plume cannot be attributed to the
  higher density in comparison to the surrounding atmosphere. Along with
  other findings, this indicates the possible presence of magnetic field.

Title: Fine structure of wave motions in the solar photosphere:
    Observations and theory
Authors: Kostyk, R. I.; Shchukina, N. G.; Khomenko, E. V.
Bibcode: 2006ARep...50..588K
Altcode:
  Spectral observations of the 639.361-nm FeI line at the center of
  the quiet solar disk with high spatial (0.4″) and temporal (10
  s) resolution are used to investigate the behavior of local 5-min
  oscillations over granules and intergranular lanes. The power of the
  5-min oscillations in the upper photosphere (at heights of H ≈ 490 km)
  is higher the faster the convective motions in the lower photosphere
  (H ≈ 10 km). This suggests that turbulent convection is responsible
  for the excitation of local solar oscillations. A statistical analysis
  of the oscillations shows that, on average, both the intensity and
  velocity of the oscillation amplitudes are greater over intergranular
  lanes. This difference in amplitudes is present throughout the studied
  heights in the photosphere (H = 0-490 km). The period at which the
  power spectrum of velocity oscillations reaches its maximum is longer
  over intergranules than over granules. Simulations of the propagation
  of acoustic-gravity waves in an atmosphere taking into account the
  convection pattern give a satisfactory explanation for the above
  observed effects. It is concluded that the atmospheric modulation
  of the 5-min oscillations is an additional or alternative mechanism
  responsible for differences between these oscillations over granules
  and intergranules.

Title: Bright features in the solar photosphere
Authors: Kostik, R. I.; Khomenko, E. V.
Bibcode: 2005KFNTS...5..141K
Altcode:
  We report thermodynamical properties of so-called ``thermal plume''
  observed near the solar disc centre in 2001. The spectral observations
  of two iron lines analysed were obtained with the use of the Vacuum
  Tower Telescope (Tenerife).

Title: Fine structure of convective motions in the solar photosphere
Authors: Kostik, R. I.
Bibcode: 2005KFNTS...5..134K
Altcode:
  The granulation brightnesses and convective velocities in the solar
  photosphere between the levels of formation of the continuum radiation
  and the temperature minimum are examined. The properties of the
  brightness and velocity are analysed in a sixteen-column model. Four
  sorts of motions are most typical and efficient. In the first two,
  only the sign of the relative contrast of the material changes, which
  occurs, on the average, at a height of 270 km. In the last two motions,
  both the sign of the contrast and the direction of the motions are
  reversed near ∼350 km. The convective motions maintain their column
  structure throughout the photosphere, right to the temperature minimum.

Title: Helioseismology space and ground-based studies
Authors: Kostik, R. I.; Osipov, S. N.; Khomenko, E. V.; Lebedev, N. I.
Bibcode: 2005KFNTS...5..138K
Altcode:
  We give a preliminary report on the observations of solar irradiance
  fluctuations with the DIFOS photometer aboard the Russian-Ukrainian
  satellite CORONAS-F launched in 2001. In addition, the parallel
  ground-based spectral observations (VTT, Tenerife) carried out with
  20-day observing space campaign are described.

Title: The Helioseismological CORONAS-F DIFOS Experiment
Authors: Lebedev, N. I.; Kuznetsov, V. D.; Oraevskii, V. N.; Staude,
   J.; Kostyk, R. I.
Bibcode: 2004ARep...48..871L
Altcode:
  The CORONAS-F DIFOS experiment continues the CORONAS-I studies
  started in 1994, devoted to investigations of solar global
  oscillations. CORONAS-F was launched July 31, 2001. Variations in
  the intensity of the solar radiation are measured in the six spectral
  intervals of the multi-channel photometer: 350, 500, 650, 850, 1100,
  and 1500 nm, with the bandwidths being about 10% of the central
  wavelength of each interval. The scientific goals of the experiment,
  a brief description of the instrument, and observational conditions
  are presented, as well as the data processing techniques. The first
  observations of the low-order p eigenmodes of the solar oscillations
  are presented for various wavelength ranges. A decrease in the relative
  amplitudes with observing wavelength is indicated. The amplitude ratios
  for various spectral ranges agree well with those detected earlier in
  ground-and space-based experiments.

Title: Fine Structure of Convective Motions in the Solar Photosphere:
    Observations and Theory
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 2004ARep...48..769K
Altcode:
  The granulation brightnesses and convective velocities in the solar
  photosphere between the levels of formation of the continuum radiation
  and the temperature minimum are examined. Spectral images of the
  granulation observed in lines of neutral and ionized iron with high
  spatial (0.5″) and temporal (9 s) resolutions were obtained using the
  German Vacuum Tower Telescope in Izana (Tenerife, Spain). A correlation
  analysis shows that the granules and intergranules change their
  relative brightness at a height near 250 km, and a general reversal
  of the velocity occurs near a height of 490 km, where the material
  above granules begins to predominantly descend, and the material above
  intergranules, to ascend. The maximum correlation coefficient between
  the velocity and the line brightnesdoesnot exceed 0.75. The properties
  of the brightness and velocity are analyzed in a sixteen-column
  model. Four sorts of motions are most typical and efficient. In the
  first two, only the sign of the relative contrast of the material
  changes (an efficiency of 46%). This occurs, on average, at a height
  of 270 km. In the last two motions, both the sign of the contrast
  and the direction of the motion are reversed near a height of 350 km
  (an efficiency of 28%). All the observed dependences are compared with
  theoretical relations obtained in a three-dimensional hydrodynamical
  model, with deviations from local thermodynamic equilibrium included
  in the calculation of the spectral-line profiles. This model can
  satisfactorily reproduce all the basic features of the convective
  velocities and intensities. It is concluded that the convective motions
  maintain their column structure throughout the photosphere, right to
  the level of the temperature minimum. This makes a separation of the
  photosphere into two regions with different granulation brightnesses
  and convective motions unjustified.

Title: Convective and wave motions in a thermal plume
Authors: Kostik, Roman I.; Khomenko, Elena V.
Bibcode: 2004IAUS..223..271K
Altcode: 2005IAUS..223..271K
  Here we report thermodynamical properties of a a so-called "thermal
  plume" observed near the solar disc center in 2001. The spectral
  observations of two iron lines analysed have been obtained using the
  Vacuum Tower Telescope (Tenerife).

Title: Helioseismology space and ground based studies
Authors: Kostik, R. I.; Osipov, S. N.; Khomenko, E. V.; Lebedev, N. I.
Bibcode: 2004IAUS..223..273K
Altcode: 2005IAUS..223..273K
  This is a preliminary report on the observations of solar irradiance
  fluctuations with the DIFOS photometer aboard the Russian-Ukrainian
  satellite CORONAS-F launched in 2001. In addition the parallel
  ground-based spectral observations (VTT, Tenerife) carried out with
  the first 20-days observing space campaign are described.

Title: The Effect of Acoustic Waves on Spectral-Line Profiles in
the Solar Atmosphere: Observations and Theory
Authors: Kostyk, R. I.; Khomenko, E. V.
Bibcode: 2002ARep...46..925K
Altcode:
  The fine structure of the FeI λ 532.4185-nm line of neutral iron is
  studied with high spatial (0.5″) and temporal (9.3 s) resolution
  using observations of a quiet region at the center of the solar
  disk. The character of the line asymmetry depends strongly on the
  nature of the velocity field, i.e., on whether it is due to convective
  or wave motions. The magnitude of the asymmetry due to acoustic waves
  is comparable to that due to convective motions. The propagation of
  acoustic waves in moving granules and intergranular lanes is studied
  by solving a system of hydrodynamical equations in a three-dimensional
  model for the solar atmosphere. The temporal variations in the bisector
  of the line synthesized in a non-LTE approximation agree well with
  the observational data.

Title: Global Oscillations of the Sun in a Wide Optical Spectral
Range: DIFOS Experiment Onboard CORONAS-F
Authors: Oraevsky, V.; Lebedev, N.; Kuznetsov, V.; Staude, J.;
   Kostyk, R.
Bibcode: 2002cosp...34E.345O
Altcode: 2002cosp.meetE.345O
  The DIFOS experiment onboard the CORONAS-F spacecraft continues the
  investigation of solar global oscillations, which was started in 1994
  during the CORONAS-I mission. The satellite was launched on July
  31, 2001. It uses a multi-channel photometer to observe irradiance
  fluctuations. The photometer measures fluctuations of the solar
  flux in six optical spectral ranges: near 350, 500, 650, 850, 1100,
  and 1500 nm with a bandwidth of about 10% of the central wavelength
  for each. After a short description of the instrumentation and data
  analyses, we present results of observations of low-degree p-modes of
  global oscillations for different observational optical ranges. The
  oscillation amplitudes were found to decrease with the growth of the
  wavelength. The amplitude ratios for different wavelength are in a
  good agreement with earlier observations and theoretical predictions.

Title: Five-minute oscillations above granules and intergranular lanes
Authors: Khomenko, E. V.; Kostik, R. I.; Shchukina, N. G.
Bibcode: 2001A&A...369..660K
Altcode:
  We discuss the links between the photospheric 5-min oscillations and
  the granulation pattern using a 30-min time series of CCD spectrograms
  of solar granulation recorded with high spatial (0{<SUP>''</SUP>}5) and
  temporal (9.3 s) resolution. The observed images contain the Fe \sc{i
  5324 Å spectral line with good height coverage from the low photosphere
  up to the temperature minimum region. Amplitudes, phases and periods
  of the 5-min oscillations are found to be different above granules
  and intergranular lanes. Strong oscillations occur well separated
  temporally and spatially. Many features of this different behaviour
  can be described in the frame of a relatively simple model of wave
  propagation in the solar atmosphere. To that aim, we have introduced
  oscillations into a 3D snapshot of a theoretical time dependent solar
  model atmosphere. NLTE synthesis of the time series of the Fe \sc{i
  5324 Å line profiles was performed taking into account granular and
  oscillatory components of the velocity field. Both, observations and
  theoretical modeling, lead to similar results: (i) oscillations above
  granules and intergranular lanes occur with different periods; (ii)
  the most energetic intensity oscillations occur above intergranular
  lanes; the most energetic velocity oscillations occur above granules
  and lanes with maximum contrast, {i.e.} above the regions with maximum
  convective velocities; (iii) velocity oscillations at the lower layers
  of the atmosphere lead oscillations at the upper layers in intergranular
  lanes. In granules the phase shift is nearly zero. We conclude that
  differences in oscillations above granules and lanes are caused mainly
  by variations of the physical conditions in these structures.

Title: Granulation and five-minute oscillations
Authors: Khomenko, E. V.; Kostik, R. I.; Shchukina, N. G.
Bibcode: 2000KFNTS...3..431K
Altcode:
  We discuss the links between the photospheric 5-min oscillations and
  granulation patterns using a 30-min time series of CCD spectral images
  of solar granulation recorded with high spatial (0.5'') and temporal
  (9.3 s) resolution. The observed images contain Fe I 5324 Å line. Our
  observations and theoretical modeling lead to the similar results:
  (i) period of oscillations varies above granules and lanes; (ii)
  amplitudes of the velocity oscillations grow with the contrast of
  granulation. Amplitudes of the intensity oscillations are larger in
  intergranular lanes than in granules. Our simple model describes the
  basic features of the oscillations above granules and intergranular
  lanes. We conclude that differences in these oscillations are caused
  mainly by variations of the physical conditions in these structures.

Title: Interaction of Granulation with the 5-min Photospheric
    Oscillations
Authors: Kostik, R. I.; Shchukina, N. G.; Khomenko, E. V.
Bibcode: 1999ESASP.448..319K
Altcode: 1999ESPM....9..319K; 1999mfsp.conf..319K
  No abstract at ADS

Title: Local 5-min oscillations above solar granules and intergranular
    space
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 1999AstL...25..678K
Altcode:
  A time series of granulation spectral images with high spatial (less
  than 0.5 arcsec) and temporal (9.3 s) resolutions has been obtained with
  the German vacuum tower telescope (VTT) on the Canary Islands in an
  effort to study the local 5-min solar oscillations. Observations were
  carried out with a CCD array in the FeI lambda 532.4185-nm line.The
  5-min intensity and velocity fluctuations near the temperature minimum,
  where this line originates, are shown to respond differently to the fine
  photospheric structure. The most energetic velocity fluctuations occur
  above the regions where the convective velocities are at a maximum;
  the main power of the velocity fluctuations above granules concentrates
  at lower frequencies than that in integranular space. The amplitude
  of the intensity fluctuations in the lambda 532.4185-nm emission above
  granules is, on the average, approximately a factor of 2 smaller.

Title: Five-minute oscillations and fine structure of the solar
    photosphere. II.
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 1999KFNT...15..135K
Altcode: 1999KNFT...15..135K
  The evolution of spectra of the solar Fe I λ 532.4185 nm line averaged
  statistically over granules and intergranules of different brightness
  are studied. The observations were carried out with the Vacuum Tower
  Telescope at the Observatorio del Teide, Tenerife. The response to
  the fine structure of the lower photosphere turns out to be clearly
  different for the five minute oscillations of the velocity and the
  intensity observed in such spectra. The amplitudes of line intensity
  oscillations above intergranular lanes are nearly two times larger
  than over granules. The power spectrum of intensity oscillations
  is dominated by high-frequency oscillations, while the velocity
  oscillations gain power in the low-frequency band. The amplitudes of
  the velocity oscillations over granules and intergranules of the same
  brightness contrast are virtually equal. The most energetic velocity
  oscillations are shown to occur over areas where the largest convective
  velocities are observed.

Title: Five-minute oscillations and the fine structure of the solar
    photosphere. I.
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 1999KFNT...15...25K
Altcode: 1999KNFT...15...25K
  The authors analyse the spatial relationship between the solar
  granulation and the local five-minute oscillations of velocity and
  intensity observed in the Fe I λ532.4185 nm line. The time series of
  CCD spectral images of solar granulation taken at the Germany Vacuum
  Tower Telescope (VTT) were recorded with high spatial (&lt;0.5 arcsec)
  and temporal (9.3 s) resolution. In the temperature minimum region,
  where the line is formed, the most energetic intensity oscillations
  are shown to occur mainly over dark intergranular lanes, while strong
  velocity oscillations are observed over granules and intergranules. The
  amplitude of the latter oscillations increases with the granulation
  brightness contrast. The spatially averaged power of intensity
  oscillations is concentrated at higher frequencies compared to the
  power of velocity oscillations.

Title: Five-minute oscillations and the fine structure of the solar
    photosphere. II.
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 1999KPCB...15..102K
Altcode:
  The authors examine the evolution of the solar Fe I λ 532.4185 nm line
  spectrum averaged over granules and intergranular lanes of different
  brightness. The five-minute velocity and intensity oscillations
  observed in this spectrum are shown to occur differently over various
  fine-structure features in the photosphere. The amplitudes of line
  intensity oscillations above intergranular lanes are nearly twice as
  large as above granules. The bulk of the power of these oscillations
  fall on high frequencies, while the velocity oscillations gain their
  power in the low-frequency band. The velocity oscillation amplitudes
  are virtually equal over granules and dark lanes of the same brightness
  contrast. The most energetic velocity oscillations are observed over
  the areas with the highest convection velocities,.

Title: Five-minute oscillations and the fine structure of the solar
    photosphere. I.
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 1999KPCB...15...16K
Altcode:
  The authors analyze the spatial relationship between the solar
  granulation and the local five-minute velocity and intensity
  oscillations observed in the Fe I λ532.4185 nm line. The spectral
  granulation images were recorded with high spatial and temporal
  resolution (&lt;0.5 arcsec and 9.3 s) at the German Vacuum Tower
  Telescope. In the temperature minimum region, where the line is
  formed, the most energetic intensity oscillations occur mainly over
  dark intergranular lanes. Strong velocity oscillations are observed
  over granules and intergranules, their amplitude increasing with
  the granulation brightness contrast. The space-averaged intensity
  oscillation power is concentrated at higher frequencies compared to
  the power of velocity oscillations.

Title: Diagnostic of the solar atmosphere using iron lines.
Authors: Shchukina, N. S.; Kostyk, R. I.; Trujillo Bueno, J.
Bibcode: 1998IBUAA..12Q..32S
Altcode:
  No abstract at ADS

Title: DIFOS helioseismological experiment.
Authors: Kostyk, R. I.; Keselman, I. G.; Osipov, S. N.; Zhugzhda,
   Yu. D.; Kopaev, I. M.; Lebedev, N. I.; Oraevskij, V. N.
Bibcode: 1998BCrAO..94..163K
Altcode:
  The DIFOS solar telescope is intended for measuring variations of
  total solar radiation on board the KORONAS spacecraft launched 1994.

Title: Problem of iron abundance in the solar photosphere.
Authors: Kostyk, R. I.; Shchukina, N. G.; Rutten, R. J.
Bibcode: 1998BCrAO..94..118K
Altcode:
  The authors analyze the causes of the discrepancies.

Title: High spatial resolution observations of the solar spectral
    lines.
Authors: Kostyk, R. I.; Shchukina, N. G.; Briand, C.
Bibcode: 1998IBUAA..12...39K
Altcode:
  No abstract at ADS

Title: The Scanner for Precise Spectrophotometry of the Sun as a Star
Authors: Osipov, S. N.; Gandzha, S. I.; Andriyenko, O. V.; Karpov,
   M. V.; Kostik, R. I.
Bibcode: 1997SoPh..172..361O
Altcode: 1997ESPM....8..361O
  The primary shortcomings of existing methods for spectrophotometry
  of the Sun as a star are discussed. A new observational method
  is proposed. This method is based on a repeated scanning of the
  Sun's image while summing the signal of each step across the solar
  disk. A device for precise spectrophotometry of the Sun as a star
  has been developed around a double-pass spectrograph. This device
  and its operation algorithm are described. Errors caused by scanning
  irregularities and seeing are estimated. Several Sun-as-a-star spectrum
  line profiles and their bisectors are presented and compared with the
  same ones from the Kitt Peak FTS solar flux atlas.

Title: The NLTE Formation of Iron Lines Used in Solar Polarimetry
Authors: Shchukina, Nataliya G.; Bueno, Javier Trujillo; Kostik,
   Roman I.
Bibcode: 1997SoPh..172..117S
Altcode: 1997ESPM....8..117S
  We study in some detail one-dimensional NLTE effects in solar
  Fei lines. The lines selected are frequently used in solar
  polarimetry, and also in studies of line asymmetries and for abundance
  determinations. Our model atom for Fei-Feii-Feiii is realistic: it takes
  account of multiplet structure and it includes over 200 bound-bound
  and bound-free transitions in detail. We use very efficient iterative
  methods for the self-consistent solution of the kinetic and radiative
  transfer equations (Auer, Fabiani Bendicho, and Trujillo Bueno,
  1994). We have applied these fast methods of solution because they
  are suitable for the investigation of 2D and 3D NLTE transfer effects
  with multilevel atoms, which constitutes the next step of our ongoing
  research project on the iron line formation problem.

Title: The Instrumentation of the Main Astronomical Observatory of
    the National Academy of Sciences of Ukraine
Authors: Kostik, R. I.; Shchukina, N. G.
Bibcode: 1997ASPC..118..372K
Altcode: 1997fasp.conf..372K
  The instrumentation and observational programs of the Solar Physics
  Department of the Main Astronomical Observatory are described. The
  observatory has two solar horizontal telescopes. The first one is the
  44 cm telescope located near Kyiv. This telescope has a spectrograph
  with a double pass system. It was designed for low scattered light
  and high spectral resolution. The second one is installed at Terskol
  High-Altitude Station in the Central Caucasus, at an altitude of 3100
  m. This 65 cm telescope with its spectrograph is used for simultaneous
  photoelectric and photographic measurements of five solar spectral
  regions in the range from 3000 Angstroms to 12000 Angstroms. One of the
  scientific programs consists in the observation of solar irradiance
  fluctuations with the DIFOS photometer aboard the Ukraine-Russian
  satellite CORONAS-I, which was launched on March 2, 1994. These space
  observations will be continued during the new mission CORONAS-F.

Title: On a new method of obtaining the Sun-as-a-star spectrum
Authors: Osipov, S. M.; Andriyenko, O. V.; Gandzha, S. I.; Karpov,
   N. V.; Kostik, R. I.
Bibcode: 1997MmSAI..68..463O
Altcode:
  No abstract at ADS

Title: The solar iron abundance: not the last word.
Authors: Kostik, R. I.; Shchukina, N. G.; Rutten, R. J.
Bibcode: 1996A&A...305..325K
Altcode:
  Determinations of the solar iron abundance have converged to the
  meteoritic value with the FeII studies of Holweger et al. (1990),
  Biemont et al. (1991) and Hannaford et al. (1992) and the FeI results
  of Holweger et al. (1991). However, the latter authors pointed out
  that Blackwell et al. (1984) obtained a discordant result from similar
  oscillator strengths. A recent debate on this lingering discrepancy
  by the Oxford and Kiel contenders themselves has not clarified
  the issue. We do so here by showing that it stems from systematic
  differences between equivalent widths and oscillator strengths which
  masquerade as difference in fitted damping enhancement factors. We first
  discuss the various error sources in classical abundance determination
  and then emulate both sides of the debate with abundance fits of our
  own. Our emulation of the Oxford side shows that the abundance anomaly
  claimed by Blackwell et al. (1984) for solar FeI 2.2eV lines vanishes
  when equivalent width measurements from other authors are combined
  with better evaluation of the collisional damping parameter. On the
  Kiel side, we find that the oscillator strengths of Bard et al. (1991)
  used by Holweger et al. (1991) produce a suspicious trend when used
  to fit solar FeI lines, whereas comparable application of oscillator
  strengths from Oxford does not. The trend is mainly set by categories
  of FeI lines not measured at Oxford; for lines of overlap the two sets
  agree and deliver the iron abundance value A_Fe_=7.62+/-0.04 which
  exceeds the meteorite value. The dissimilar lines may suffer from
  solar line-formation effects. We conclude that the issue of the solar
  iron abundance remains open. Definitive oscillator strengths are still
  needed, as well as verification of classical abundance determination
  by more realistic representations of the solar photosphere and of
  photospheric line formation.

Title: Device for precise spectrophotometry of the Sun as a star.
Authors: Gandzha, S. I.; Osipov, S. N.; Karpov, N. V.; Kolokolova,
   L. O.; Kostyk, R. I.
Bibcode: 1996KPCB...12a..71G
Altcode: 1996KPCB...12...71G
  A device for precise spectrophotometry of the Sun as a star has been
  developed around a double-pass solar monochromator. The device and
  its operation algorithm are described. Errors caused by scanning
  irregularities and seeing are estimated. Some results of test
  observations are presented.

Title: Is the problem of solar iron abundance solved?
Authors: Kostik, R. I.; Shchukina, N. G.
Bibcode: 1995AdSpR..15g..69K
Altcode: 1995AdSpR..15...69K
  We revise the solar photospheric abundance of iron from Fe I lines
  based on two scales of oscillator strengths gf (Oxford [1-6] and Kiel
  [7]). In order to answer the question of Holweger et al. [8] why the
  gf of both scales agree but abundances deviate, we analyse different
  sources of errors in the solar iron abundance determinations. The
  most important reason of the abundance discrepancy is connected with
  the damping enhancement factor, E. However, the results obtained do
  not allow to infer a final value of the solar iron abundance. The
  ``high'' abundance derived from the Oxford scale of gf [2] seems to be
  more preferable in view of a smaller root mean square error epsilon in
  the iron abundance determination and a more pronounced minimum of the
  function epsilon(E) in comparison with the ``low'' abundance case [8].

Title: Solar Irradiance Oscillations: Preliminary Results of the
    Coronas-Difos Experiment
Authors: Lebedev, N. I.; Oraevsky, V. N.; Zhugzhda, Y. D.; Kopaev,
   I. M.; Kostyk, R. I.; Pflug, K.; Rüdiger, G.; Staude, J.; Bettac,
   H. -D.
Bibcode: 1995ESASP.376b.353L
Altcode: 1995soho....2..353L; 1995help.confP.353L
  No abstract at ADS

Title: First results of the CORONAS-DIFOS experiment. Space
    observations of solar irradiance oscillations.
Authors: Lebedev, N. I.; Oraevsky, V. N.; Zhugzhda, Y. D.; Kopaev,
   I. M.; Kostyk, R. I.; Pflug, K.; Ruediger, G.; Staude, J.; Bettac,
   H. -D.
Bibcode: 1995A&A...296L..25L
Altcode:
  The DIFOS experiment aboard the satellite CORONAS has been designed to
  observe irradiance fluctuations due to global solar oscillations. The
  satellite was launched on March 2, 1994. It uses a photometer measuring
  fluctuations of the solar flux in three channels: near 550nm, 750nm,
  and from 400nm through 1.1μm. After a short description of the
  instrumentation and the data analysis we present first, preliminary
  results of observations of low-degree p-modes including their variation
  in time.

Title: The Determination of the Solar Iron Abundance from Fe I Lines
Authors: Kostik, R. I.; Shchukina, N. G.; Rutten, R. J.
Bibcode: 1995ASPC...78..399K
Altcode: 1995aapn.conf..399K
  No abstract at ADS

Title: Space Helioseismology Experiment DIFOS
Authors: Zhugzhda, Y. D.; Oraevsky, V. N.; Lebedev, N. I.; Kopaev,
   I. M.; Kostyk, R. I.; Keselman, I. G.; Osipov, S. N.
Bibcode: 1995ASPC...76..436Z
Altcode: 1995gong.conf..436Z
  No abstract at ADS

Title: Does the iron abundance anomaly obtained from the 2.2 eV Fe
    I lines really exist in the solar atmosphere?
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 1994KFNT...10...51K
Altcode: 1994KNFT...10...51K
  No abstract at ADS

Title: In memoriam Ernest Andreyevich Gurtovenko (10 December 1928 -
    20 January 1994).
Authors: Kostik, R. I.
Bibcode: 1994SoPh..152D...6K
Altcode: 1994SoPh..152.....K
  No abstract at ADS

Title: Photometer ``difos'' for the study of solar brightness
    variations
Authors: Gurtovenko, E. A.; Kesel'Man, I. G.; Kostyk, R. I.; Osipov,
   S. N.; Lebedev, N. I.; Kopayev, I. M.; Orajevsky, V. N.; Zhugzhda,
   Yu. D.
Bibcode: 1994SoPh..152...43G
Altcode: 1994svs..coll...43G; 1994IAUCo.143...43G
  A photometer has been designed for measuring solar irradiance within
  three wide spectral bands with a relative error 0.00001 and time
  resolution of 16 sec. It is elaborated according to the international
  space project KORONAS and is planned to be launched at the begining
  of 1994. A description of its layout and operation is given briefly.

Title: Is the problem of solar iron abundance solved?
Authors: Kostyk, R. I.; Shchukina, N. G.
Bibcode: 1994KFNT...10...54K
Altcode: 1994KNFT...10...54K
  The authors revised the solar iron abundance from photospheric Fe
  I lines using two scales of oscillator strengths gf. The first one
  is Oxford high-precision laboratory measurements of Fe I transition
  probabilities. The second scale recently obtained in a hollow-cathode
  experiment by Bard et al. differs from the former by 0.03 dex in the
  absolute scale. The abundance values A = 7.64±0.04 and A = 7.50±0.07
  respectively were determined. In order to explain the puzzle why gf
  of both scales agree but abundances deviate the authors have analysed
  the possible sources of errors in determinations of solar abundance.

Title: Investigations of the Sun.
Authors: Gurtovenko, Eh. A.; Kostyk, R. I.
Bibcode: 1994maof.conf..189G
Altcode:
  No abstract at ADS

Title: Conference of the problem group "Radiation and structure of
    the Sun", held in L'vov, 23 - 25 September 1991.
Authors: Gurtovenko, Eh. G.; Kostyk, R. I.
Bibcode: 1992KFNT....8...91G
Altcode: 1992KNFT....8...91G
  No abstract at ADS

Title: Time variability of absorption lines in the solar spectrum.
Authors: Kostyk, R. I.
Bibcode: 1991KFNT....7...48K
Altcode: 1991KNFT....7...48K
  The conclusion of Babij (1991) obtained from an analysis of variation
  of central depths of Fraunhofer lines observed in 1960 - 1985 seems to
  be doubtful. The conclusion is that up to some level (in the region
  where weak absorption lines are formed) the solar photosphere is in
  stationary state, and above that level the solar photosphere may be
  considered as unstationary.

Title: Variability with time of absorption lines in the solar
    spectrum.
Authors: Kostyk, R. I.
Bibcode: 1991KPCB....7e..43K
Altcode: 1991KPCB....7...43K
  B. T. Babii's conclusion (1991) that the Sun's photosphere is in a
  stationary state up to a certain level (in the formation region of
  weak absorption lines) and nonstationary above that level, which was
  obtained from analysis of the variations of Fraunhofer-line central
  depths observed in 1960 - 1985 is placed in doubt.

Title: Fine structure of the Fraunhofer lines - Observation results
    and their interpretation
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostyk, R. I.
Bibcode: 1990KFNT....6R...3A
Altcode:
  Observation results on line asymmetry and absolute line shift in the
  spectra of the solar photosphere are presented and their theoretical
  interpretation is discussed. Empirical data are presented on the
  line asymmetry and line shifts for the center of the solar disk,
  for center-to-limb transition, for the spectrum of the sun as a star,
  and for active regions. Data are also presented concerning variations
  of line asymmetry as a function of the phase of the solar cycle. The
  semiempirical approach to the interpretation of Fraunhofer line
  asymmetry and absolute line shifts is also discussed. The results of
  a multidimensional numerical simulation of convective motions in the
  superadiabatic region and in the solar photosphere are presented.

Title: Fine structure of the Fraunhofer lines: observation results
    and their interpretation.
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostyk, R. I.
Bibcode: 1990KNFT....6R...3A
Altcode:
  The review embraces results of the spectral line observations and
  their theoretical interpretation. The empirical data on the line
  asymmetry and absolute wavelength shifts are presented for the solar
  centre, for different positions on the solar limb and for the Sun as a
  star. Their dependence on the phase of the solar activity cycle is also
  reviewed. Interpretation of these data on the basis of semiempirical
  models is discussed. The multidimensional numerical simulation results
  of convective motions in the superadiabatic region and in the solar
  photosphere are presented.

Title: Analysis of Absorption Line Profiles in the Spectra of the
    Sun and Procyon - Velocity Field and Size of Inhomogeneities
Authors: Gadun, A. S.; Kostyk, R. I.
Bibcode: 1990SvA....34..260G
Altcode:
  No abstract at ADS

Title: Analysis of absorption line profiles in the solar and Procyon
spectra : velocity field and sizes of turbulent eddies.
Authors: Gadun, A. S.; Kostyk, R. I.
Bibcode: 1990AZh....67..520G
Altcode:
  It is shown that the turbulent velocity and the sizes of turbulent
  eddies in the Procyon atmosphere are 1.5-2.5 times larger than in
  the solar atmosphere. A comparative analysis of the variation of
  these parameters with height revealed substantial differences between
  convection processes on the sun and Procyon.

Title: Statistical Regularities in the Solar Spectrum
Authors: Kostyk, R. I.; Perekhod, A. V.
Bibcode: 1990SvAL...16..111K
Altcode:
  No abstract at ADS

Title: Statistical regularities in the solar spectrum
Authors: Kostik, R. I.; Perekhod, A. V.
Bibcode: 1990PAZh...16..260K
Altcode:
  The paper examines the dependence of halfwidth and equivalent width for
  Fe I lines on their excitation potential observed in the solar spectrum
  (Babiia, 1988). It is shown that the dependence can be explained within
  the framework of the modern theory of the formation of spectral lines.

Title: Comparative Analysis of Physical Conditions in the Solar and
    Procyon Atmospheres
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostik, R. I.; Pikalov,
   K. N.
Bibcode: 1990IAUS..138..421A
Altcode:
  No abstract at ADS

Title: Solar Oscillator Strengths as a Diagnostic Tool
Authors: Gurtovenko, E. A.; Kostik, R. I.; Rutten, R. J.
Bibcode: 1990IAUS..138...35G
Altcode:
  No abstract at ADS

Title: New solar oscillator strengths from Kiev
Authors: Gurtovenko, E. A.; Kostik, R. I.; Rutten, R. J.
Bibcode: 1990asos.conf...92G
Altcode:
  No abstract at ADS

Title: Modeling of convective motions in the envelope of
    procyon. II. Asymmetry of the spectral lines
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostyk, R. I.
Bibcode: 1989Ap.....31..765A
Altcode: 1990Ap.....31..765A
  No abstract at ADS

Title: Modeling of convective motions in the envelope of
    procyon. I. ideology and analysis of three-dimensional models
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostyk, R. I.
Bibcode: 1989Ap.....31..580A
Altcode: 1990Ap.....31..580A
  No abstract at ADS

Title: Three-Dimensional Simulation of Convective Motions in the
    Procyon Envelope
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostik, R. I.
Bibcode: 1989ASIC..263..521A
Altcode: 1989ssg..conf..521A
  No abstract at ADS

Title: Solar spectroscopy.
Authors: Jackiv, J. S.; Kostyk, R. I.; Schukina, N. G.
Bibcode: 1989Rise...70...12J
Altcode:
  No abstract at ADS

Title: Asymmetry of Absorption Lines in the Solar and Procyon Spectra
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostik, R. I.
Bibcode: 1989ASIC..263..135A
Altcode: 1989ssg..conf..135A
  No abstract at ADS

Title: The Simulation of the Convective Motions in the Procyon
    Envelope - Part Two - Spectral Line Asymmetries
Authors: Atroschenko, F. N.; Gadun, A. S.; Kostyk, R. I.
Bibcode: 1989Afz....31..589A
Altcode:
  No abstract at ADS

Title: Fraunhofer spectrum and a system of solar oscillator strengths
Authors: Gurtovenko, Ernest A.; Kostyk, Roman I.
Bibcode: 1989KiIND.........G
Altcode:
  Results of research concerned with the Fraunhofer spectrum of the sun
  and problems associated with this type of research are reviewed in
  a historical perspective. Solar dual-diffraction monochromators are
  described, and methods of observing the Fraunhofer spectrum with a
  high spectral resolution are discussed. Results of studies concerned
  with the development of solar oscillator forces, determined from the
  Fraunhofer lines, are reviewed. Oscillator force values are presented
  for 1958 spectral lines of 49 chemical elements in the wavelength
  range 303-996 nm.

Title: Fraungoferov spektr i sistema solnechnykh sil ostsilliatorov
Authors: Gurtovenko, Ernest Andreevich; Kostyk, Roman Ivanovich
Bibcode: 1989fsss.book.....G
Altcode: 1989QB551.G87......
  No abstract at ADS

Title: The simulation of the convective motions in the Procyon
    envelope. I. Ideology and analysis of the three-dimensional
    inhomogeneous models.
Authors: Atroshchenko, I. N.; Gadun, A. S.; Kostyk, R. I.
Bibcode: 1989Afz....31..281A
Altcode:
  No abstract at ADS

Title: Book Review: The galaxy and the solar system. / U Arizona
    Press, 1986.
Authors: Kotov, V. A.; Kostik, R.; Shchukina, N.; Švestka, Zdeněk;
   Kotov, V. A.
Bibcode: 1988SoPh..115..203K
Altcode: 1988SoPh..115..203S
  No abstract at ADS

Title: Empirical gf-determination from the solar spectrum
Authors: Rutten, Robert J.; Kostik, Roman I.
Bibcode: 1988ASSL..138...83R
Altcode: 1988IAUCo..94...83R; 1988pffl.proc...83R
  The reliability of Fe I and Fe II oscillator strengths determined
  empirically from optical solar lines is tested. A comparison is made
  between gfW fits to the equivalent widths and gfD fits to the depths
  of 354 Fe I lines and 22 Fe II lines for various combinations of input
  parameters. The resulting scatter diagrams provide a measure of the
  attainable precision.

Title: Rotation of the Solar Atmosphere at Different Altitudes
Authors: Gadun, A. S.; Kostyk, R. I.; Sheminova, V. A.
Bibcode: 1987SvA....31..557G
Altcode:
  No abstract at ADS

Title: The rotation of the solar atmosphere at different altitudes
Authors: Gadun, A. S.; Kostyk, R. I.; Sheminova, V. A.
Bibcode: 1987AZh....64.1066G
Altcode:
  A new method for determining the solar rotation velocity is proposed. A
  comparison was made between the observed central depths of Fraunhofer
  lines in the spectrum of the sun as a star and calculations based on
  center-limb observations. For altitudes in the range of 100-1100 km
  above the level of the continuous spectrum, the solar rotation velocity
  hardly changes.

Title: The oscillator strengths of the lines of rare earth elements
Authors: Glavnaia Astronomicheskaia Observatoriia; Kostyk, R. I.;
   Karpov, N. V.
Bibcode: 1987KFNT....3...14G
Altcode:
  The oscillator strengths of 76 lines of eight rare earth elements are
  determined from the observed equivalent widths and central depths of
  the solar Fraunhofer lines. A comparison is made between the present
  values and experimental values obtained over the last 10 yrs.

Title: Oscillator strengths of rare earths.
Authors: Karpov, N. V.; Kostyk, R. I.
Bibcode: 1987KFNT....3...14K
Altcode:
  Oscillator strengths for 76 lines of eight rare earths are determined
  from observed equivalent widths, and central depths of solar Fraunhofer
  lines.

Title: Abundances of the elements of the palladium group in the
    solar atmosphere.
Authors: Kostyk, R. I.
Bibcode: 1987BSolD1987...92K
Altcode:
  Abundances of five elements of the palladium group are determined in
  the solar atmosphere: A(Y) = 2.25±0.08, A(Zr) = 2.54±0.14, A(Nb) =
  1.67±0.08, A(Mo) = 1.96±0.02, A(Tc) ≤ -0.6.

Title: Estimation of technetium abundance in the solar photosphere.
Authors: Kostyk, R. I.; Perekhod, A. V.
Bibcode: 1986KFNT....2...38K
Altcode:
  On the basis of the analysis of 8 short spectral regions of the
  undisturbed solar photosphere it is concluded that the technetium
  abundance in the solar atmosphere does not exceed lg A(Tc) = -0.6 on
  the scale lg A(H) = 12.0.

Title: Oscillator strengths of iron lines.
Authors: Kostyk, R. I.; Orlova, T. V.
Bibcode: 1986KFNT....2...63K
Altcode:
  Oscillator strengths of 380 iron lines have been determined from the
  observed central intensities and equivalent widths of the Fraunhofer
  solar lines with r.m.s. error not exceeding 12%.

Title: Book reviews
Authors: Gurtovenko, E. A.; Kostik, R. I.; Tlamicha, A.; Zerull, R.;
   Schadee, Aert; Mészáros, A.; Néeman, Y.; Giese, R. H.; Sinclair,
   A. T.; Kleczek, J.; Trendelenburg, E. A.; Hillebrandt, Wolfgang;
   Sehnal, L.; de Graaff, W.; Slottje, C.; Courvisier, T.; van Beek,
   H. F.; Baud, B.; de Jager, C.; Danby, J. M. A.; Somov, B. V.;
   Cassinelli, J.; Verbunt, F.
Bibcode: 1986SSRv...44..177G
Altcode:
  No abstract at ADS

Title: Book-Review - Spectral Line Shapes
Authors: Rostas, F.; Gurtovenko, E. A.; Kostik, R. I.
Bibcode: 1986SSRv...44..177R
Altcode:
  No abstract at ADS

Title: The establishment of internally consistent solar scales of
    oscillatorstrengths and abundances of chemical elements. Zirconium.
Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V.
Bibcode: 1986KFNT....2...20G
Altcode:
  Oscillator strengths for 19 Zr I lines (r.m.s. error±0.078 dex) and
  10 Zr II lines (±0.081 dex) are determined from observed equivalent
  widths and central depths of solar Fraunhofer lines. The analysis of
  the differences of oscillator strengths derived from equivalent widths
  and from central depths leads to the conclusion that the lines under
  study have no essential hyperfine structure.

Title: Rotation of the solar photosphere from observations of central
    depthsof Fraunhofer lines.
Authors: Gadun, A. S.; Kostyk, R. I.; Sheminova, V. A.
Bibcode: 1985KFNT....1R..53G
Altcode:
  The solar rotation velocity for different heliographic latitudes has
  been found from comparison of the central depths of Fraunhofer lines
  in the spectrum of the sun as a star with the central depths of the
  same lines at different distances from the solar centre.

Title: The fine structure of Fraunhofer lines in the spectrum of
    the sun as a star.
Authors: Gadun, A. S.; Kostyk, R. I.
Bibcode: 1985KFNT....1...24G
Altcode: 1985KFNT....1R..24G
  The Fraunhofer lines in the spectrum of integrated sunlight are shown
  to have asymmetries similar to the asymmetry of the spectrum of the
  solar disk centre. It is found that the asymmetry varies with line
  strength and does not practically depend on the lower level excitation
  potential, ionization degree and atomic weight.

Title: Oscillator strengths for the lines of the iron group elements.
Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V.
Bibcode: 1985KFNT....1....3G
Altcode:
  The significance of the work on the establishment of the solar gf-scales
  for the Fraunhofer lines of the elements of the iron group is evaluated
  in general, and the results of the work are summed up. The information
  on the number of lines investigated is given as well as on the number
  of corresponding publications. The comparison of the solar gf-scales
  with the highest precision values of the oscillator strengths for
  selected lines obtained in Oxford gives the r.m.s. internal error of
  the solar gf-scales ≤0.07 dex.

Title: On the establishment of internally consistent solar scales of
    oscillator strengths and abundances of chemical elements. VI. Neutral
    vanadium.
Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V.
Bibcode: 1985KFNT....1...62G
Altcode:
  Oscillator strengths of 55 lines of neutral vanadium are determined
  from equivalent widths of solar Fraunhofer lines using the procedure
  developed by the authors and reported in the previous papers.

Title: Fine Structure of Fraunhofer Lines and the Structure of the
    Solar Atmosphere
Authors: Kostyk, R. I.
Bibcode: 1985SvA....29...65K
Altcode:
  No abstract at ADS

Title: Fine structure of Fraunhofer lines and the structure of the
    solar atmosphere
Authors: Kostyk, R. I.
Bibcode: 1985AZh....62..112K
Altcode:
  On the basis of data on the fine structure (asymmetry) of weak
  Fraunhofer lines observed in the spectrum of the center of the solar
  disk, a semiempirical inhomogeneous model of the solar atmosphere
  is proposed which explains: (1) the fine structure of moderate and
  moderately strong Fraunhofer lines at the center of the solar disk;
  (2) the change in the sign of the asymmetry of absorption lines
  from positive to negative in the center-to-limb transition; (3)
  the asymmetry of absorption lines formed in a granule and a porule;
  (4) the weak dependence of the fine structure of Fraunhofer lines
  on the atomic parameters; and (5) the shifts of absorption lines at
  different distances from the center of the solar disk. A fundamental
  difference of the model from those proposed earlier is the absence
  of correlation between the direction of motion of convective elements
  and their brightness.

Title: On the establishment of internally consistent solar scales of
    oscillator strengths and abundances of chemical elements. VII. Mn I.
Authors: Gurtovenko, Eh. A.; Kostyk, R. I.; Orlova, T. V.
Bibcode: 1984BSolD1984...85G
Altcode:
  Oscillator strengths of 30 Mn I lines are determined up to ±(0.06 -
  0.07) dex from the equivalent widths of solar Fraunhofer lines.

Title: On the Establishment of Internally Consistent Solar Scales
    of Oscillator Strengths and Abundances of Chemical Elements - Part
    Seven - Mni
Authors: Gurtovenko, E. A.; Kostik, R. I.; Orlova, T. V.
Bibcode: 1984BSolD...9...85G
Altcode:
  No abstract at ADS

Title: Construction of Internally Consistent Scales of Solar
    Oscillator Strengths and Contents of Chemical Elements - Determination
    of Coi Oscillator Strengths from the Equivalent Widths of Fraunhofer
    Lines with Allowance for Their Hyperfine Structure
Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V.
Bibcode: 1983SvA....27..439G
Altcode:
  No abstract at ADS

Title: Construction of internally consistent scales of solar
    oscillator strengths and contents of chemical elements Determination
    of CO I oscillator strengths from the equivalent widths of Fraunhofer
    lines with allowance for their hyperfine structure
Authors: Gurtovenko, E. A.; Kostik, R. I.; Orlova, T. V.
Bibcode: 1983AZh....60..758G
Altcode:
  The authors use the observed equivalent widths of 50 Co I lines and
  cobalt abundance lg A = 4.98 to derive the oscillator strengths (gf)
  of these lines. In addition, for 14 lines from the total list the
  oscillator strengths (gf<SUB>HFS</SUB>) were obtained with accounting
  for their hyperfine structure. Clear dependences of the difference lg
  gf - lg gf<SUB>HFS</SUB> on equivalent width and excitation potential
  are revealed. Using these dependences, the authors have corrected all
  the oscillator strengths obtained without accounting for the hyperfine
  structure.

Title: Oscillator strengths of lines of ionized titanium and chromium
Authors: Kostyk, R. I.; Orlova, T. V.
Bibcode: 1983AAfz...49...39K
Altcode:
  Oscillator strengths for 27 Ti II lines and 29 Cr II lines in the
  solar atmosphere were determined with an accuracy of + or - 0.15
  dex. Estimates of titanium and chromium concentrations in the solar
  atmosphere are presented.

Title: Mesoturbulence
Authors: Kostyk, R. I.
Bibcode: 1983AAfz...48...10K
Altcode:
  It is shown that the mean velocity of mesoturbulent motions in
  the solar photosphere (the Kubo-Anderson processing being used) is
  depth-independent and amounts to xi = 1.75 km/s. The correlation length
  decreases with height from 750 km (lg tau = 0.8) to 350 km (lg tau =
  -1.7). The relation xi-squared = v-squared(micro) + v-squared(macro)
  is accurately satisfied for the photosphere.

Title: Sizes of Turbulence Elements in the Solar Atmosphere
Authors: Kostyk, R. I.
Bibcode: 1982SvA....26..703K
Altcode:
  No abstract at ADS

Title: Sizes of turbulence elements in the solar atmosphere
Authors: Kostyk, R. I.
Bibcode: 1982AZh....59.1167K
Altcode:
  The sizes of turbulent vortices at different heights in the solar
  atmosphere are determined. It is assumed that the sizes of turbulent
  vortices are distributed in accordance with a Poisson law while their
  velocities obey a Gaussian law. The number of turbulence elements
  occurring along a length having an optical depth of unity in the
  continuum, the root-mean-square velocity, and the correlation length are
  found from well-known spectral relationships and a described calculation
  procedure. It is found that the average size of turbulent vortices
  in the solar atmosphere decreases with height from 670 to 440 km,
  while their root-mean-square velocity is constant and equal to 1.7 km/s.

Title: Empirical NLTE analyses of solar spectral lines. III - Iron
    lines versus LTE models of the photosphere
Authors: Rutten, R. J.; Kostik, R. I.
Bibcode: 1982A&A...115..104R
Altcode:
  We compare observational indications of departures from LTE in
  solar Fe I lines with published NLTE computations in the context of
  discrepancies between empirical LTE and NLTE models of the solar
  atmosphere. We find that the importance of departures from LTE in
  Fe I and similar spectra is often underestimated through neglect of
  opacity departures. We demonstrate with numerical experiments that the
  peculiarities of the LTE models are artifacts due to the neglect of NLTE
  departures; in particular, we so explain the Holweger-Müller LTE model
  quantitatively. However, we show also that the NLTE formation of most
  optical metal lines is fortuitously well-mimicked by LTE computation
  when using LTE models. Thus, LTE-derived metal abundances and empirical
  oscillator strengths happen to be fairly precise. The same may hold
  for the use of theoretical radiative- equilibrium models in stellar
  abundance determinations.

Title: Oscillator strengths for neutral titanium lines
Authors: Kostyk, R. I.
Bibcode: 1982AZh....59..693K
Altcode:
  No abstract at ADS

Title: Oscillator Strengths for Neutral Titanium Lines
Authors: Kostyk, R. I.
Bibcode: 1982SvA....26..422K
Altcode:
  No abstract at ADS

Title: Damping Constant and Turbulence in the Solar Atmosphere
Authors: Kostik, R. I.
Bibcode: 1982SoPh...78...39K
Altcode:
  In the region of the formation of weak and medium-strong lines,
  the microturbulence increases with height (V<SUB>ver</SUB>=0.7-0.9
  km s<SUP>-1</SUP>, V<SUB>hor</SUB>= 1.1-1.5 km s<SUP>-1</SUP>),
  the macroturbulence decreases (V<SUB>ver</SUB>=1.6-1.4 km
  s<SUP>-1</SUP>, V<SUB>hor</SUB>= 2.4-1.5 km s<SUP>-1</SUP>), and
  the total velocity field (vertical component) is depth-independent
  (1.7 km s<SUP>-1</SUP>). The empirical damping constants for Fe,
  Ti, Cr, Ni lines are equal 1.3<SUB>γ6</SUB>, 1.7<SUB>γ6</SUB>,
  1.6<SUB>γ6</SUB>, 1.6<SUB>γ6</SUB>, respectively. The correlation
  length (the Kubo-Anderson process has been used) in the solar
  photosphere is 520-550 km.

Title: On the establishment of internally consistent solar scales
    of oscillator strengths and abundances of chemical elements. III -
    Oscillator strengths obtained from equivalent widths of 360 FeI lines
Authors: Gurtovenko, E. A.; Kostik, R. I.
Bibcode: 1982A&AS...47..193G
Altcode:
  Oscillator strengths for 360 selected Fraunhofer lines were determined
  using the observed equivalent widths of those lines. The R.M.S. error
  of the gf-values obtained amounts to 0.06-0.07 dex. The comparison
  of oscillator strengths calculated from equivalent widths (w) and
  central intensity (d) shows the reliability of the methods used and
  of the underlaying data. The systematic increase of the difference log
  gf<SUB>W</SUB> - log gf<SUB>d</SUB> for strong lines of high excitation
  potential is noticeable.

Title: Oscillator strengths for lines of neutral nickel.
Authors: Kostyk, R. I.
Bibcode: 1982AAfz...46...58K
Altcode:
  The oscillator strengths of 175 Ni lines in the solar atmosphere were
  determined from central intensities of solar Fraunhofer lines. The
  accuracy of the determination was + or - 0.09 dex.

Title: The oscillator strengths of ionized iron lines
Authors: Kostyk, R. I.; Orlova, T. V.
Bibcode: 1982AAfz...47...32K
Altcode:
  The method used in calculating the strengths from the equivalent width
  is the same as that described by Gurtovenko and Kostyk (1980), where
  residual intensities were used. The values used for the velocity of the
  microturbulent motions and for the damping constant and iron abundance
  in the solar photosphere are consistent with the results obtained by
  Kostyk (1981). The calculations are carried out on the basis of the
  HOLMU model, described by Holweger and Muller (1974). The equivalent
  widths of the solar lines are taken from the studies of, among others,
  Biemont (1978) and Blackwell et al. (1980). A table giving the strengths
  of 59 lines is included.

Title: Mesoturbulence in the Solar Atmosphere
Authors: Kostik, R. I.
Bibcode: 1982ASSL...96..105K
Altcode: 1982spls.meet..105K
  No abstract at ADS

Title: On the establishment of internally consistent solar
    scales of oscillator strengths and abundances of chemical
    elements. I. Oscillator strengths for 865 FeI lines iron abundance.
Authors: Gurtovenko, E. A.; Kostik, R. I.
Bibcode: 1981A&AS...46..239G
Altcode:
  A method is developed for the establishment of internally consistent
  scales for solar abundances and oscillator strengths and used to deduce
  the solar iron abundance and the oscillator strengths for 865 Fe I
  lines. The method involves the calculation of L, defined as the product
  of the abundance with the oscillator strength, which can be inferred
  from the line profiles, equivalent widths, central intensities and
  the entire Fraunhofer spectrum of the specific chemical element. In
  the iron study, abundance and oscillator strengths are derived from
  unblended central intensities of lines in the region 4000-8000 A taking
  into account the influence of macroturbulence velocities. An average
  iron abundance of 7.525 + or - 0.007 is obtained from 266 weak and
  moderately strong lines appearing in the oscillator strength scale of
  May et al. (1974). The obtained abundance was then used to calculate
  the oscillation strengths of all 612 weak and moderate Fe I lines and
  the remaining strong lines to within + or - 0.035 dex.

Title: On the Establishment of Internally Consistent Solar Scales of
    Oscillator Strengths and Abundances of Chemical Elements - Part Two -
    on the Errors of the Oscillator Strengths of FEI Lines in the Kurucz
Authors: Gurtovenko, E. A.; Kostik, R. I.
Bibcode: 1981A&A...101..132G
Altcode:
  It is shown that the errors on the oscillator strengths of the
  Kurucz-Peytremann gf-scale depend in a regular way upon the excitation
  potential and gf-value. Oscillator strengths with small values
  of gf and large excitation potentials are underestimated, and vice
  versa. Especially strong underestimations (by ≍2 orders of magnitude)
  of the oscillator strengths take place for the lines with excitation
  potentials EPL &gt; 4 eV and oscillator strengths log gf &lt; -4.0.

Title: Interpretation of Center-To Profiles of Weak Fraunhofer Lines
Authors: Kostyk, R. I.
Bibcode: 1981SvA....25..343K
Altcode:
  No abstract at ADS

Title: The interpretation of center-limb profiles of weak Fraunhofer
    lines
Authors: Kostyk, R. I.
Bibcode: 1981AZh....58..604K
Altcode:
  Profiles of weak Fraunhofer lines have been analyzed under the
  assumption that nonthermal broadening and asymmetry of the lines are
  caused by wave and convective motions. A comparison of computed and
  observed line profiles shows that a horizontal flow with a velocity of
  2.7 km/s exists on the major part of the sun's surface. The upflow
  velocity is 0.9 km/s, and the granule-intergranule temperature
  difference is about 330 K.

Title: Oscillator strengths for lines of neutral chromium
Authors: Kostyk, R. I.
Bibcode: 1981AAfz...45....3K
Altcode:
  Microturbulence and macroturbulence velocities and the damping constant
  in the solar atmosphere were determined from Fraunhofer lines of
  neutral chromium and found to equal 0.8 km/s, 1.1 km/s, and 2.0 gamma
  (6) respectively. Oscillator strengths of 123 Cr I lines have been
  determined with an accuracy of 0.19 dex.

Title: On the Establishment of Internally Consistent
    Abundance-Oscillator Strength Scales
Authors: Gurtovenko, E. A.; Kostik, R. I.
Bibcode: 1980LNP...114..296G
Altcode: 1980IAUCo..51..296G; 1980sttu.coll..296G
  No abstract at ADS

Title: Formation of the Profiles of Absorption Lines in the
    Inhomogeneous Medium
Authors: Kostik, R. I.
Bibcode: 1980LNP...114...53K
Altcode: 1980sttu.coll...53K; 1980IAUCo..51...53K
  No abstract at ADS

Title: On the microturbulence in the solar photosphere.
Authors: Kostik, R. I.; Orlova, T. V.
Bibcode: 1979SoPh...62...89K
Altcode:
  The velocity of microturbulent motions in the solar photosphere at the
  level of formation of weak Fraunhofer lines (h ∼ 150 km) is found to
  be 0.1 ± 0.2 km s<SUP>−1</SUP>. The observations have been performed
  with the double-pass spectrometer in Kiev. Apart from thermal motions
  and damping effects we have taken into account convective and wave
  motions when calculating the broadening of absorption lines.

Title: Formation of absorption lines in an inhomogeneous medium
Authors: Kostyk, R. I.; Perekhod, A. V.
Bibcode: 1979AAfz...39...40K
Altcode:
  Fraunhofer lines asymmetry and its variations have been studied
  by means of convection, acoustic wave, and temperature fluctuation
  mechanisms. The present work analyzes Fraunhofer line profiles employing
  all these three mechanisms. Emphasis is placed on horizontal motions
  in a convective cell. An asymmetry value obtained theoretically is
  less than that of the observed one.

Title: Double-diffraction monochromator of the Kiev-Golosseevo
    Observatory with a digital system for automation of observations
    and solar-spectrum processing
Authors: Gurtovenko, E. A.; Kostyk, R. I.
Bibcode: 1979AAfz...39...88G
Altcode:
  No abstract at ADS

Title: Effect of a travelling sound wave on the profiles of spectral
    lines. V.
Authors: Kostyk, R. I.; Perekhod, A. V.
Bibcode: 1978AAfz...34....3K
Altcode:
  The previous papers were concerned with the calculation of line-center
  intensity fluctuations and Fraunhofer line shifts caused by acoustic
  waves. The present paper deals with the calculation of the asymmetry
  of the contour of the absorption coefficient of Fe lines (with
  various lower-level excitation potentials) at various heights of the
  solar atmosphere. Calculations are carried out on the basis of the
  Harvard-Smithsonian reference atmosphere, assuming that the photosphere
  in locally homogeneous and optically thin; that waves propagate only
  in the vertical direction; and that the input equations are linear. It
  is shown that the asymmetry of Fe I lines with excitation potentials
  below 2 eV is negative, but is positive for excitation potentials
  greater than 3 eV. The asymmetry of Fraunhofer lines increases in the
  transition from the photosphere to the chromosphere, and decreases
  with increasing damping constant.

Title: On the asymmetry of selected Fraunhofer lines.
Authors: Kostik, R. I.; Orlova, T. V.
Bibcode: 1977SoPh...53..353K
Altcode:
  An analysis is made of the asymmetry of Fraunhofer lines observed
  with the double-pass monochromator of the horizontal solar telescope
  ASU-5 of the Main Astronomical Observatory of the Ukrainian Academy of
  Sciences. The conclusion is that the character of macromotion in the
  radial direction varies with height; in a tangential direction the
  motions at different depths are homogeneous. The asymmetry of weak
  lines is due to convection rather than to wave motions.

Title: Shift of Fraunhofer lines in the solar spectrum.
Authors: Kostyk, R. I.
Bibcode: 1977AAfz...31...48K
Altcode:
  No abstract at ADS

Title: On the asymmetry of selected Fraunhofer lines. IV.
Authors: Kostyk, R. I.; Orlova, T. V.
Bibcode: 1977AAfz...33...51K
Altcode:
  The asymmetry of nine Fe I and Ni I Fraunhofer lines was studied at five
  different positions on the solar disk (cos theta = 1, 0.80, 0.60, 0.44,
  and 0.28), in order to obtain information on macroturbulent motions
  in the tangential direction. Asymmetry was characterized by a single
  parameter, defined as the ratio of the third- and second-order central
  moments of the function 1 - r(lambda), where r(lambda) is the residual
  line intensity. For all positions, the asymmetry decreases as equivalent
  width increases. At the center-limb transition the asymmetry of each
  line decreases and changes sign at some distance from the center. At
  the limb all the lines have negative asymmetry. This reveals that in
  the photosphere there are horizontal macroscopic motions besides radial
  ones. Studying the behavior of the asymmetry along a line profile from
  core to tail reveals that weak lines and tails of strong lines are
  formed in deeper layers than the cores of strong lines. This points
  to the different character of macromotions in the photosphere.

Title: On the interpretation of Fraunhofer-line profiles
Authors: Kostyk, R. I.; Gerbil'Skaya, I. M.
Bibcode: 1976SvA....20..704K
Altcode:
  No abstract at ADS

Title: On the interpretation of Fraunhofer-line profiles
Authors: Kostyk, R. I.; Gerbil'Skaya, I. M.
Bibcode: 1976AZh....53.1244K
Altcode:
  No abstract at ADS

Title: Asymmetry of the infrared triplet lines of oxygen and
    determination of the relative content of isotopes O<SUP>17</SUP>
    and O<SUP>18</SUP> in the solar photosphere
Authors: Kostyk, R. I.
Bibcode: 1976AZh....53..125K
Altcode:
  No abstract at ADS

Title: Asymmetry of the infrared triplet lines of oxygen and
    determination of the relative content of isotopes O<SUP>17</SUP>
    and O<SUP>18</SUP> in the solar photosphere
Authors: Kostyk, R. I.
Bibcode: 1976SvA....20...67K
Altcode:
  No abstract at ADS

Title: On the asymmetry of selected Fraunhofer lines. III.
Authors: Kostyk, R. I.; Orlova, T. V.; Gerbilskaia, I. M.
Bibcode: 1976AAfz...29...89K
Altcode:
  The asymmetry of 10 Fraunhofer lines observed with a horizontal solar
  telescope and a double-diffraction monochromator is examined as a
  function of equivalent width and lower-level excitation potential. The
  lines, all produced by neutral species, span the spectral range from
  5811.919 to 7807.916 A. During processing of the observational data, the
  line profiles were smoothed both before and after being corrected for
  instrument-contour error. It is found that the asymmetry is 'positive'
  for all lines except the oxygen IR triplet at 7771.954, 7774.177,
  and 7775.395 A. The results also show that the asymmetry does not
  depend on excitation potential and decreases as the equivalent width
  increases. Possible reasons for the last two findings are considered.

Title: On the Possible Mechanism of Formation of Emission Rim in
    Hydrogen Filaments
Authors: Kostik, R. I.; Orlova, T. V.
Bibcode: 1975SoPh...45..119K
Altcode:
  Hα filtergrams of the chromosphere show an emission rim in many
  hydrogen filaments. We suppose that formation of this rim is due to
  photospheric radiation reflected by the filament in the direction of
  the chromosphere. The calculations show that: (1) the maximum contrast
  of the rim relative to the undisturbed chromosphere amounts to 1.4;
  (2) the larger the optical thickness of the filament and the closer to
  the solar limb it is situated, the brighter and wider is the rim; (3)
  the rim was not observed in filaments whose heights exceeds 10000km
  above the chromosphere. These results are in close agreement with
  observations.

Title: Profiles of selected Fraunhofer lines for different positions
    center-limb on the solar disk.
Authors: Gurtovenko, Eh. A.; Kostyk, R. I.; Orlova, T. V.; Troyan,
   V. I.; Fedorchenko, G. L.; Morozhenko, N. N.
Bibcode: 1975psfl.book.....G
Altcode:
  No abstract at ADS

Title: Profiles of selected Fraunhofer lines for various center-limb
    positions on the solar disk
Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V.; Troian,
   V. I.; Fedorchenko, G. L.
Bibcode: 1975KiIND....Q....G
Altcode:
  The profiles of 98 Fraunhofer lines are tabulated for five positions
  (cos theta equals 1.00, 0.80, 0.60, 0.44, and 0.28) on the disk of
  the quiet sun. The data are based primarily on observations in the
  wavelength range 5700 to 6400 A made with a double solar spectrometer.

Title: Effect of a progressive sound wave on the profiles of spectral
lines. 2: Asymmetry of faint Fraunhofer lines
Authors: Kostyk, R. I.
Bibcode: 1974amap.nasa...56K
Altcode:
  The absorption coefficient profile was calculated for lines of different
  chemical elements in a medium with progressive sound waves. Calculations
  show that (1) the degree and direction of asymmetry depend on the atomic
  ionization potential and the potential of lower level excitation of
  the individual line; (2) the degree of asymmetry of a line decreases
  from the center toward the limb of the solar disc; and (3) turbulent
  motions 'suppress' the asymmetry.

Title: On the Asymmetry of Selected Fraunhofer Lines, II
Authors: Kostik, R. I.; Orlova, T. V.
Bibcode: 1974SoPh...36..279K
Altcode:
  The asymmetry of 11 absorption lines of neutral iron was determined
  from observations made with the double-pass system on the horizontal
  solar telescope Asu-5. An attempt was made to interpret this asymmetry
  in terms of progressive sound waves. The value of asymmetry computed
  theoretically was shown to be on average only 20 % of the observed
  value.

Title: Influence of a progressive sound wave on the profiles of
    spectral lines. IV. Shift of the iron lines in the spectrum of the
    sun's centre.
Authors: Kostyk, R. I.
Bibcode: 1974AAfz...23...52K
Altcode:
  No abstract at ADS

Title: Matrix Equations of Radiation Diffusion. IV.
Authors: Kostyk, R. I.
Bibcode: 1973aars.conf..163K
Altcode:
  No abstract at ADS

Title: Asymmetry of Selected Fraunhofer Lines. I.
Authors: Kostyk, R. I.; Orlova, T. V.
Bibcode: 1973aars.conf..150K
Altcode:
  No abstract at ADS

Title: Effect of a traveling sound wave on the profiles of spectral
    lines. I. Central intensity oscillations of the Fraunhofer lines.
Authors: Kostyk, R. I.
Bibcode: 1973AAfz...18...94K
Altcode:
  No abstract at ADS

Title: Effect of progressive sound wave on the profiles of spectral
    lines. III. Shift of faint Fraunhofer lines.
Authors: Kostyk, R. I.
Bibcode: 1973AAfz...19...44K
Altcode:
  No abstract at ADS

Title: The Interpretation of Absorption-Line Shifts in the Solar
    Spectrum
Authors: Kostik, R. I.; Orlova, T. V.
Bibcode: 1972SoPh...26...42K
Altcode:
  The shifts of Fraunhofer lines of different chemical elements in a
  homogeneous medium with a plane monochromatic progressive adiabatic
  sound waves are derived. The calculations indicate that lines of neutral
  elements (6 ⩽ χ<SUB>0</SUB> ⩽ 14) with lower excitation potentials
  χ<SUB>0</SUB>i= 0-2 eV are red shifted, those with excitation potential
  χ<SUB>0</SUB>i= 4-12 eV are blue shifted, and with χ<SUB>0</SUB>i=
  3 eV are both blue and red shifted. The lines of ions are shifted
  toward the blue. The shifts of Fraunhofer lines are found to decrease
  from the centre of the solar disk to the limb. These results agree
  qualitatively and quantitatively with observations.

Title: Ionization and Excitation of Helium in Prominences.
Authors: Kostik, R. I.
Bibcode: 1972SvA....15..582K
Altcode:
  No abstract at ADS

Title: Effect of a progressive sound wave on the profiles of spectral
    lines. II. Asymmetry of faint Fraunhofer lines.
Authors: Kostyk, R. I.
Bibcode: 1972AAfz...17...50K
Altcode:
  No abstract at ADS

Title: Ionization and Excitation of Helium in Prominences.
Authors: Kostik, R. I.
Bibcode: 1971AZh....48..738K
Altcode:
  No abstract at ADS

Title: On the diffusion of the L<SUB>c</SUB>-emission in prominences.
Authors: Kostyk, R. I.
Bibcode: 1971BSolD1971...80K
Altcode:
  No abstract at ADS

Title: On the asymmetry of selected Fraunhofer lines.
Authors: Kostik, R. I.; Orlova, T. V.
Bibcode: 1970AAfz....9..117K
Altcode:
  No abstract at ADS

Title: Matrix Equations of Radiation Diffusion. IV.
Authors: Kostyk, R. I.
Bibcode: 1970asas.book..163K
Altcode:
  No abstract at ADS

Title: The matrix equations of the diffusion of radiation. IV.
Authors: Kostik, R. I.
Bibcode: 1970AAfz....9..128K
Altcode:
  No abstract at ADS

Title: Asymmetry of Selected Fraunhofer Lines. I.
Authors: Kostyk, R. I.; Orlova, T. V.
Bibcode: 1970asas.book..150K
Altcode:
  No abstract at ADS

Title: Matrix equations of radiation diffusion. III
Authors: Kostik, R. I.
Bibcode: 1967Ap......3...76K
Altcode:
  No abstract at ADS

Title: Matrix equations for radiation diffusion. II
Authors: Kostik, R. I.
Bibcode: 1967Ap......3....6K
Altcode:
  No abstract at ADS

Title: Matrix equations for radiation diffusion. II.
Authors: Kostik, R. I.
Bibcode: 1967Afz.....3...17K
Altcode:
  No abstract at ADS

Title: Matrix equations for radiation diffusion. I
Authors: Yakovkin, N. A.; Kostik, R. I.
Bibcode: 1966Ap......2..197Y
Altcode:
  No abstract at ADS

