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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.
2022KFNT...38...71S Altcode:
No abstract at ADS
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Title: Solar Faculae: Microturbulence as an Indicator of Inclined
Magnetic Fields
Authors: Stodilka, M. I.; Kostyk, R. I.
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.
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Title: Solar faculae: microturbulence as an indicator of inclined
magnetic fields
Authors: Stodilka, M. I.; Kostyk, R. I.
2020KFNT...36d...3S Altcode:
No abstract at ADS
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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.
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.
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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.
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.
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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.
2020KFNT...36a...3S Altcode: 2020KFNT...36....3S
No abstract at ADS
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Title: Features of Convection in the Atmospheric Layers of the
Solar Facula
Authors: Stodilka, M. I.; Prysiazhnyi, A. I.; Kostyk, R. I.
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.
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Title: Features of convection in the atmosphere layers of the
solar facula
Authors: Stodilka, M. I.; Prysiazhnyi, A. I.; Kostyk, R. I.
2019KFNT...35f..18S Altcode:
No abstract at ADS
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Title: Effect of wave motions in the active region of the solar
surface on convection
Authors: Kostik, R. I.
2018KFNT...34b..46K Altcode:
No abstract at ADS
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Title: Effect of Wave Motions in the Active Region of the Solar
Surface on Convection
Authors: Kostyk, R. I.
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%.
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Title: Kyiv monitoring program of spectral line variations with the
11-year cycle
Authors: Shchukina, Nataliia; Osipov, Sergej; Kostyk, Roman; Stodilka,
Myroslav
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.
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Title: Kyiv monitoring program of fraunhofer lines variation with
11-year cycle of solar activity
Authors: Osipov, Sergii; Kostik, Roman; Shchukina, Nataliia
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&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.
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Title: Monitoring program of selected Fraunhofer lines over the
11-year cycle of solar activity
Authors: Osipov, S.; Kostik, R.; Shchukina, N.
2017psio.confE.109O Altcode:
No abstract at ADS
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Title: Two Spectra of Turbulence of the Sun
Authors: Kostik, R.; Kozak, L.; Cheremnykh, O.
2017psio.confE.108K Altcode:
No abstract at ADS
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Title: The possible origin of facular brightness in the solar
atmosphere
Authors: Kostik, R.; Khomenko, E.
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.
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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.
2015KPCB...31..188K Altcode:
No abstract at ADS
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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.
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.
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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.
2014KPCB...30...40K Altcode:
No abstract at ADS
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Title: Properties of oscillatory motions in a facular region
Authors: Kostik, R.; Khomenko, E.
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.
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Title: Two spectra of turbulence of the sun
Authors: Kozak, L. V.; Kostyk, R. I.; Cheremnykh, O. K.
2013KPCB...29...66K Altcode:
No abstract at ADS
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Title: What are solar faculae?
Authors: Kostyk, R. I.
2013KPCB...29...32K Altcode:
No abstract at ADS
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Title: Different Modes of Turbulence in the Active Regions of the
Solar Photosphere
Authors: Kozak, L. V.; Kostik, R. I.; Cheremnykh, O. K.
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.
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Title: Properties of convective motions in facular regions
Authors: Kostik, R.; Khomenko, E. V.
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.
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Title: Magnetic field effect on the fine structure of convective
motions in the solar atmosphere
Authors: Kostyk, R. I.
2012KPCB...28..155K Altcode:
No abstract at ADS
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Title: Some properties of convective motions in the upper solar
atmosphere. II
Authors: Kostyk, R. I.
2011KPCB...27..175K Altcode:
No abstract at ADS
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Title: Peculiarities of convective motions in the upper solar
atmosphere. I
Authors: Kostyk, R. I.
2010KPCB...26..233K Altcode:
No abstract at ADS
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Title: Solar granulation from photosphere to low chromosphere observed
in Ba II 4554 Å line
Authors: Kostik, R.; Khomenko, E.; Shchukina, N.
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.
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Title: Observations of a bright plume in solar granulation
Authors: Kostik, R. I.; Khomenko, E. V.
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.
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Title: Fine structure of wave motions in the solar photosphere:
Observations and theory
Authors: Kostyk, R. I.; Shchukina, N. G.; Khomenko, E. V.
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.
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Title: Bright features in the solar photosphere
Authors: Kostik, R. I.; Khomenko, E. V.
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).
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Title: Fine structure of convective motions in the solar photosphere
Authors: Kostik, R. I.
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.
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Title: Helioseismology space and ground-based studies
Authors: Kostik, R. I.; Osipov, S. N.; Khomenko, E. V.; Lebedev, N. I.
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.
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Title: The Helioseismological CORONAS-F DIFOS Experiment
Authors: Lebedev, N. I.; Kuznetsov, V. D.; Oraevskii, V. N.; Staude,
J.; Kostyk, R. I.
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.
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Title: Fine Structure of Convective Motions in the Solar Photosphere:
Observations and Theory
Authors: Kostyk, R. I.; Shchukina, N. G.
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.
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Title: Convective and wave motions in a thermal plume
Authors: Kostik, Roman I.; Khomenko, Elena V.
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).
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Title: Helioseismology space and ground based studies
Authors: Kostik, R. I.; Osipov, S. N.; Khomenko, E. V.; Lebedev, N. I.
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.
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Title: The Effect of Acoustic Waves on Spectral-Line Profiles in
the Solar Atmosphere: Observations and Theory
Authors: Kostyk, R. I.; Khomenko, E. V.
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.
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.
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.
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.
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.
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.
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.
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 (<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.
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.
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 (<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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
1990SvAL...16..111K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Statistical regularities in the solar spectrum
Authors: Kostik, R. I.; Perekhod, A. V.
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.
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.
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.
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.
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.
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.
1989ASIC..263..521A Altcode: 1989ssg..conf..521A
No abstract at ADS
---------------------------------------------------------
Title: Solar spectroscopy.
Authors: Jackiv, J. S.; Kostyk, R. I.; Schukina, N. G.
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.
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.
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.
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
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
1986SSRv...44..177G Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Book-Review - Spectral Line Shapes
Authors: Rostas, F.; Gurtovenko, E. A.; Kostik, R. I.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
1982SvA....26..703K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Sizes of turbulence elements in the solar atmosphere
Authors: Kostyk, R. I.
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.
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.
1982AZh....59..693K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Oscillator Strengths for Neutral Titanium Lines
Authors: Kostyk, R. I.
1982SvA....26..422K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Damping Constant and Turbulence in the Solar Atmosphere
Authors: Kostik, R. I.
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.
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.
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.
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.
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.
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.
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 > 4 eV and oscillator strengths log gf < -4.0.
---------------------------------------------------------
Title: Interpretation of Center-To Profiles of Weak Fraunhofer Lines
Authors: Kostyk, R. I.
1981SvA....25..343K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: The interpretation of center-limb profiles of weak Fraunhofer
lines
Authors: Kostyk, R. I.
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.
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.
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.
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.
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.
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.
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.
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.
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.
1977AAfz...31...48K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: On the asymmetry of selected Fraunhofer lines. IV.
Authors: Kostyk, R. I.; Orlova, T. V.
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.
1976SvA....20..704K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: On the interpretation of Fraunhofer-line profiles
Authors: Kostyk, R. I.; Gerbil'Skaya, I. M.
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.
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.
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.
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.
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.
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.
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.
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.
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.
1974AAfz...23...52K Altcode:
No abstract at ADS
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Title: Matrix Equations of Radiation Diffusion. IV.
Authors: Kostyk, R. I.
1973aars.conf..163K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Asymmetry of Selected Fraunhofer Lines. I.
Authors: Kostyk, R. I.; Orlova, T. V.
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.
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.
1973AAfz...19...44K Altcode:
No abstract at ADS
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Title: The Interpretation of Absorption-Line Shifts in the Solar
Spectrum
Authors: Kostik, R. I.; Orlova, T. V.
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.
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.
1972AAfz...17...50K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Ionization and Excitation of Helium in Prominences.
Authors: Kostik, R. I.
1971AZh....48..738K Altcode:
No abstract at ADS
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Title: On the diffusion of the L<SUB>c</SUB>-emission in prominences.
Authors: Kostyk, R. I.
1971BSolD1971...80K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: On the asymmetry of selected Fraunhofer lines.
Authors: Kostik, R. I.; Orlova, T. V.
1970AAfz....9..117K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Matrix Equations of Radiation Diffusion. IV.
Authors: Kostyk, R. I.
1970asas.book..163K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: The matrix equations of the diffusion of radiation. IV.
Authors: Kostik, R. I.
1970AAfz....9..128K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Asymmetry of Selected Fraunhofer Lines. I.
Authors: Kostyk, R. I.; Orlova, T. V.
1970asas.book..150K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Matrix equations of radiation diffusion. III
Authors: Kostik, R. I.
1967Ap......3...76K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Matrix equations for radiation diffusion. II
Authors: Kostik, R. I.
1967Ap......3....6K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Matrix equations for radiation diffusion. II.
Authors: Kostik, R. I.
1967Afz.....3...17K Altcode:
No abstract at ADS
---------------------------------------------------------
Title: Matrix equations for radiation diffusion. I
Authors: Yakovkin, N. A.; Kostik, R. I.
1966Ap......2..197Y Altcode:
No abstract at ADS
