Author name code: gurtovenko ADS astronomy entries on 2022-09-14 author:"Gurtovenko, Ernest Andreivich" ------------------------------------------------------------------------ Title: Formation depths of Fraunhofer lines Authors: Gurtovenko, E. A.; Sheminova, V. A. Bibcode: 2015arXiv150500975G Altcode: We have summed up our investigations performed in 1970--1993. The main task of this paper is clearly to show processes of formation of spectral lines as well as their distinction by validity and by location. For 503 photospheric lines of various chemical elements in the wavelength range 300--1000 nm we list in Table the average formation depths of the line depression and the line emission for the line centre and on the half-width of the line, the average formation depths of the continuum emission as well as the effective widths of the layer of the line depression formation. Dependence of average depths of line depression formation on excitation potential, equivalent widths, and central line depth are demonstrated by iron lines. Title: Formation depth of Fraunhofer lines Authors: Gurtovenko, E. A.; Sheminova, V. A. Bibcode: 1997MAO.....1P...3G Altcode: We have summed up our investigations performed in 1970-1993 which were devoted to the problem of the effective depths of spectral absorption line formation. The main purpose of this paper is to show the difference in the effectiveness of the various physical processes responsible for the line absorption formation as well as to present Tables of line formation depths. The 503 photospheric lines of various chemical elements in the wavelength range 300-1000 nm were used for our calculations. We list in the Tables the formation depths of both depression and emission in line center and line half-width as well as the average formation depths of the continuum emission for the corresponding wavelengths. Additionally in the Tables, we give the effective widths of the formation region of each absorption line. The change of the average formation depths of iron lines in dependence on excitation potential, equivalent widths, and central line intensity are demonstrated on Figures. Title: A Big Horizontal Solar Telescope of the Main Astronomical Observatory of the Ukrainian National Academy of Sciences in the caucasus Authors: Burlov-Vasil'Ev, K. A.; Vasil'Eva, I. E.; Gurtovenko, E. A.; Matveev, Yu. B. Bibcode: 1996R&QE...39..887B Altcode: This paper presents the Big Horizonal Solar Telescope of the Main Astronomical Observatory of the Ukrainian National Academy of Sciences installed at the “Peak Terskol” high-altitude station near Elbrus (the main mirror diameter is 650 mm and the focal length is 17.5 m). The telescope is equipped with a five-camera spectrograph intended for photographic spectral observations of active regions in the solar atmosphere and photoelectric measurements of the solar spectra with high spectral and spatial resolution. The observation procedure is described, and the results of the quality analysis of the recorded spectra and of the early measurements are presented. Title: New absolute measurements of the solar spectrum 310 685 nm Authors: Burlov-Vasiljev, K. A.; Gurtovenko, E. A.; Matvejev, Yu. B. Bibcode: 1995SoPh..157...51B Altcode: During 1986-1989 at the high-altitude station on the Peak Terskol, Caucasus (h = 3000 m) absolute measurements of the solar disk-centre intensity were performed. The observations were carried out with the specialized solar telescope (D = 23 cm,F = 3 m) and grating spectrometer (F = 2 m, grating 140 × 150 mm, 600 grooves mm−1). The ribbon tungsten lamps used for absolute calibration were calibrated to the USSR standard of spectral intensity and were also compared with the irradiance standard of the PMO/WRC (Davos, Switzerland), with the lamps used in the Alma-Ata Observatory (Kazakhstan) and in Simferopol University for absolute measurements of stellar spectra. Methods and apparatus were improving step by step during 1985-1988. Special care was paid to the study of all possible sources of errors, in particular to the method of correction for atmospheric extinction, to polarization properties of optical elements of the apparatus, and to establishing the most reliable absolute calibration system. Finally, the observations performed during 1989 utilized only the refined methods and apparatus. As a result, the absolute integrals of the solar disk-centre intensity for 1-nm wide spectral bands in the range 310-685 nm are available. We estimate the total error is 2.5% at 310 nm and 2.1% at 680 nm. The absolute irradiance for 5-nm wide spectral bands is also obtained. We compare our results with results by Neckel and Labs (1984), with the irradiance filter measurements performed in PMO/WRC and calibration of the Sun's spectral irradiance to the stellar irradiance standard Vega by Lockwood (1992). Our results show a systematic difference with data by Neckel and Labs in the near-ultraviolet. The results by Neckel and Labs are probably underestimated in this spectral range by 8%. Title: Photometer ``difos'' for the study of solar brightness variations Authors: Gurtovenko, E. A.; Kesel'Man, I. G.; Kostyk, R. I.; Osipov, S. N.; Lebedev, N. I.; Kopayev, I. M.; Orajevsky, V. N.; Zhugzhda, Yu. D. Bibcode: 1994SoPh..152...43G Altcode: 1994svs..coll...43G; 1994IAUCo.143...43G A photometer has been designed for measuring solar irradiance within three wide spectral bands with a relative error 0.00001 and time resolution of 16 sec. It is elaborated according to the international space project KORONAS and is planned to be launched at the begining of 1994. A description of its layout and operation is given briefly. Title: The Solar Radiation Between 310-680 nm Authors: Burlov-Vasiljev, K. A.; Gurtovenko, E. A.; Matvejev, Yu. B. Bibcode: 1992sers.conf...49B Altcode: No abstract at ADS Title: What is the difference between `emission' and `depression' contribution functions? Authors: Gurtovenko, E. A.; Sheminova, V. A.; Sarychev, A. P. Bibcode: 1991SoPh..136..239G Altcode: The right approach to the problem of the depth of Fraunhofer line formation enables us to distinguish the main processes involved in the formation of a Fraunhofer line and to locate the depths for these processes in the photosphere. Title: Observation of Solar Eclipse in Mexico 1991JUL11 for Solar Diameter Determination Authors: Gurtovenko, E. A.; Telnyuk-Adamchuk, V. V.; Okulov, S. M.; Buzdugan, J. P.; Olijnyk, P. O. Bibcode: 1991ATsir1550...29G Altcode: No abstract at ADS Title: Absolute spectrophotometry of the Sun. I. The formulation of the problem and method of solution. Authors: Burlov-Vasil'Ev, K. A.; Gurtovenko, E. A.; Matveev, Iu. B.; Troian, V. I. Bibcode: 1990KFNT....6...33B Altcode: 1990KNFT....6...33B A brief review of the problem of absolute solar spectrophotometry is given. The necessity of fulfilment of a new set of measurements, calibrated by the USSR standard of the spectral density of the energy brightness is substantiated. The demands to the equipment are formulated. The error sources are discussed and the analysis of their reduction is given. The method of the measurements is motivated. Title: Solar Oscillator Strengths as a Diagnostic Tool Authors: Gurtovenko, E. A.; Kostik, R. I.; Rutten, R. J. Bibcode: 1990IAUS..138...35G Altcode: No abstract at ADS Title: New solar oscillator strengths from Kiev Authors: Gurtovenko, E. A.; Kostik, R. I.; Rutten, R. J. Bibcode: 1990asos.conf...92G Altcode: No abstract at ADS Title: Fraunhofer spectrum and a system of solar oscillator strengths Authors: Gurtovenko, Ernest A.; Kostyk, Roman I. Bibcode: 1989KiIND.........G Altcode: Results of research concerned with the Fraunhofer spectrum of the sun and problems associated with this type of research are reviewed in a historical perspective. Solar dual-diffraction monochromators are described, and methods of observing the Fraunhofer spectrum with a high spectral resolution are discussed. Results of studies concerned with the development of solar oscillator forces, determined from the Fraunhofer lines, are reviewed. Oscillator force values are presented for 1958 spectral lines of 49 chemical elements in the wavelength range 303-996 nm. Title: The solution of the transfer equation for absorption and the depth of Fraunhofer-line formation Authors: Gurtovenko, E. A.; Sarychev, A. P. Bibcode: 1988AZh....65..653G Altcode: It is proved that the contribution function obtained previously as a result of solution of the transfer equation for depression, is identically equal to the contribution function of Unsöld-Pecker. Title: On the possibility to improve the homogeneous photospheric model of the Sun. Authors: Gurtovenko, E. A.; Sheminova, V. A. Bibcode: 1988KFNT....4...18G Altcode: Modelling of differences of solar oscillator strengths derived from equivalent widths and central intensities with variations of nominal temperature of the photospheric model and characteristics of the photospheric velocity field has been made. The accuracy of determining chemical element abundances is evaluated by applying the specific uncertainties of the distribution of temperature and velocity field amplitude in the solar photosphere. The investigations of temperature and luminosity variations of the Sun from precise observations of Fraunhofer lines may bring fruitful results. The line symmetry of light elements with high excitation potential may serve as a "sensitive" indicator of physical inhomogeneity of solar and stellar atmospheres. Title: Solution of the Transfer Equation for Absorption and the Depth of Formation of Fraunhofer Lines Authors: Gurtovenko, E. A.; Sarychev, A. P. Bibcode: 1988SvA....32..337G Altcode: No abstract at ADS Title: Crossing Method for Studying the Turbulence in Solar and Stellar Atmospheres - Part One - Application to the Sun Authors: Gurtovenko, E. A.; Sheminova, V. A. Bibcode: 1986SoPh..106..237G Altcode: A new `crossing' method for the study of turbulent velocities in solar and stellar photospheres is considered. The method does not need knowledge of the abundance and oscillator strengths for determining the microturbulent velocity, if the macroturbulent velocity is adopted; or it allows investigation of the micro- and macro-velocities simultaneously, if the abundance and oscillator strengths are known. Using the crossing method for 200 lines of neutral iron we obtain microturbulent velocities for a large range of depths in the solar photosphere. The distribution of macroturbulent velocities with depth is also investigated. The total velocity field calculated from the obtained micro- and macro-velocities agrees with previous results from independent methods. This demonstrates the reliability of using the crossing method for separate determination of the micro- and macroturbulent velocities in solar and stellar atmospheres. Title: Integral spectrum of the sun as a star in UV (0.1 - 0.32 μm) and IR (1 - 50 μm) regions. Authors: Burlov-Vasilev, K. A.; Gurtovenko, E. A.; Troian, V. I. Bibcode: 1986KFNT....2....3B Altcode: The measurements of the spectral energy distribution of the sun as a star in ultraviolet and infrared are reviewed. The standard distribution in UV is deduced from an analysis of the most important 11 series of independent observations of the 20th and 21st cycles. This distribution is shown to differ from the widely used Makarova and Kharitonov's set in UV, while for the IR region the set by Makarova and Kharitonov is at present the most reliable one. Title: Scattered light in a spectrograph and its effect on the measured darkening to the solar limb. Authors: Gurtovenko, E. A.; Osipov, S. N. Bibcode: 1986KFNT....2...59G Altcode: The procedure of corrections of observed solar limb darkening for the influence of spectrograph scattered light is presented. The measurements of scattered light in the first order of diffraction carried out by three different methods agree well. With the chosen filters the corrections are shown to be insignificant for most of the region of the spectrum. Title: Book reviews Authors: Gurtovenko, E. A.; Kostik, R. I.; Tlamicha, A.; Zerull, R.; Schadee, Aert; Mészáros, A.; Néeman, Y.; Giese, R. H.; Sinclair, A. T.; Kleczek, J.; Trendelenburg, E. A.; Hillebrandt, Wolfgang; Sehnal, L.; de Graaff, W.; Slottje, C.; Courvisier, T.; van Beek, H. F.; Baud, B.; de Jager, C.; Danby, J. M. A.; Somov, B. V.; Cassinelli, J.; Verbunt, F. Bibcode: 1986SSRv...44..177G Altcode: No abstract at ADS Title: Book-Review - Spectral Line Shapes Authors: Rostas, F.; Gurtovenko, E. A.; Kostik, R. I. Bibcode: 1986SSRv...44..177R Altcode: No abstract at ADS Title: The establishment of internally consistent solar scales of oscillatorstrengths and abundances of chemical elements. Zirconium. Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V. Bibcode: 1986KFNT....2...20G Altcode: Oscillator strengths for 19 Zr I lines (r.m.s. error±0.078 dex) and 10 Zr II lines (±0.081 dex) are determined from observed equivalent widths and central depths of solar Fraunhofer lines. The analysis of the differences of oscillator strengths derived from equivalent widths and from central depths leads to the conclusion that the lines under study have no essential hyperfine structure. Title: On the difference in the depths of formation of the centers of weak Fraunhofer lines and the far wings of strong ones Authors: Gurtovenko, E. A.; Sheminova, V. A. Bibcode: 1985AZh....62..988G Altcode: The Voigt function H(a,v) influences the absorption coefficient of the centre and of the wing of a Fraunhofer line differently. The absorption coefficient of the line centre is K(0) ≡ N/ΔλD, and the one of the far wings is K(v) ≡ Nγ. Here N is the concentration of absorbing atoms, ΔλD is the Doppler width, γ is the damping-broadening constant, sharply increasing downward into the photosphere. Due to this, the effective depths of formation of far wings of strong lines are larger than those of weak lines having the same atomic parameters. Title: On the difference in the depths of formation of the centers of weak Fraunhofer lines and the far wings of strong ones Authors: Gurtovenko, É. A.; Sheminova, V. A. Bibcode: 1985SvA....29..578G Altcode: No abstract at ADS Title: On the Difference in the Depths of Formation of the Centers of Weak Fraunhofer Lines and the Far Wings of Strong Ones Authors: Gurtovenko, E. A.; Sheminova, V. A. Bibcode: 1985SvA....29..572G Altcode: No abstract at ADS Title: Oscillator strengths for the lines of the iron group elements. Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V. Bibcode: 1985KFNT....1....3G Altcode: The significance of the work on the establishment of the solar gf-scales for the Fraunhofer lines of the elements of the iron group is evaluated in general, and the results of the work are summed up. The information on the number of lines investigated is given as well as on the number of corresponding publications. The comparison of the solar gf-scales with the highest precision values of the oscillator strengths for selected lines obtained in Oxford gives the r.m.s. internal error of the solar gf-scales ≤0.07 dex. Title: On the establishment of internally consistent solar scales of oscillator strengths and abundances of chemical elements. VI. Neutral vanadium. Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V. Bibcode: 1985KFNT....1...62G Altcode: Oscillator strengths of 55 lines of neutral vanadium are determined from equivalent widths of solar Fraunhofer lines using the procedure developed by the authors and reported in the previous papers. Title: Velocity Field in the Region of the Temperature Minimum of the Solar Atmosphere - Preliminary Results of a Determination of the Amplitude of the General Velocity Field Authors: Gurtovenko, E. A.; Sheminova, V. A.; Rutten, R. J. Bibcode: 1985SvA....29...72G Altcode: No abstract at ADS Title: Velocity field in the region of the temperature minimum of the solar atmosphere - Preliminary results of a determination of the amplitude of the general velocity field Authors: Gurtovenko, E. A.; Sheminova, V. A.; Rutten, R. J. Bibcode: 1985AZh....62..124G Altcode: The weak Fraunhofer lines in the near wings of H, K Ca II lines have been analysed to study the velocity amplitude of the general velocity field in the middle and outer photospheric layers. The results confirm the basic well-known data on the velocity amplitude in the middle photospheric layers. Besides, it is shown that the radial and tangential components of the velocity amplitude continue to decrease with height also in the outer photosphere. Title: Establishment of internally consistent solar scales of oscillator strenghts and abundances of chemical elements. V. Scandium. Authors: Gurtovenko, E. A.; Kostyk, P. I.; Orlova, T. V. Bibcode: 1985KFNT....1...75G Altcode: Oscillator strengths for 31 selected Sc I and Sc II lines were determined using the observed equivalent widths of the Fraunhofer lines. Title: On the Establishment of Internally Consistent Solar Scales of Oscillator Strengths and Abundances of Chemical Elements - Part Seven - Mni Authors: Gurtovenko, E. A.; Kostik, R. I.; Orlova, T. V. Bibcode: 1984BSolD...9...85G Altcode: No abstract at ADS Title: Depth of formation of Fraunhofer lines Authors: Gurtovenko, É. A.; Sheminova, V. A. Bibcode: 1983AZh....60..982G Altcode: A straightforward physical discussion of the processes of formation of the emergent photospheric radiation and the line depression observed on the continuum background has been made. Title: Depth of Formation of Fraunhofer Lines Authors: Gurtovenko, E. A.; Sheminova, V. A. Bibcode: 1983SvA....27..568G Altcode: No abstract at ADS Title: Construction of Internally Consistent Scales of Solar Oscillator Strengths and Contents of Chemical Elements - Determination of Coi Oscillator Strengths from the Equivalent Widths of Fraunhofer Lines with Allowance for Their Hyperfine Structure Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V. Bibcode: 1983SvA....27..439G Altcode: No abstract at ADS Title: Construction of internally consistent scales of solar oscillator strengths and contents of chemical elements Determination of CO I oscillator strengths from the equivalent widths of Fraunhofer lines with allowance for their hyperfine structure Authors: Gurtovenko, E. A.; Kostik, R. I.; Orlova, T. V. Bibcode: 1983AZh....60..758G Altcode: The authors use the observed equivalent widths of 50 Co I lines and cobalt abundance lg A = 4.98 to derive the oscillator strengths (gf) of these lines. In addition, for 14 lines from the total list the oscillator strengths (gfHFS) were obtained with accounting for their hyperfine structure. Clear dependences of the difference lg gf - lg gfHFS 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: Solar physics at the Main Astronomical Observatory of the Ukrainian Academy of Sciences Authors: Gurtovenko, E. A. Bibcode: 1982SoPh...80..317G Altcode: A brief review of the research highlights at the Main Astronomical Observatory since 1968. Title: The Empirical Determination of Damping Constants in the Solar Photosphere - Part Two - Results Inferred from the Wings of FEI Lines Authors: Gurtovenko, E. A.; Fedorchenko, G. L.; Kondrashova, N. N. Bibcode: 1982SoPh...77..291G Altcode: We determine empirical damping constants for 73 selected Fe I lines following the method of Gurtovenko and Kondrashova (1980), employing high-quality observations and the accurate list of Fe I oscillator strengths by Gurtovenko and Kostik (1980). Title: On the establishment of internally consistent solar scales of oscillator strengths and abundances of chemical elements. III - Oscillator strengths obtained from equivalent widths of 360 FeI lines Authors: Gurtovenko, E. A.; Kostik, R. I. Bibcode: 1982A&AS...47..193G Altcode: Oscillator strengths for 360 selected Fraunhofer lines were determined using the observed equivalent widths of those lines. The R.M.S. error of the gf-values obtained amounts to 0.06-0.07 dex. The comparison of oscillator strengths calculated from equivalent widths (w) and central intensity (d) shows the reliability of the methods used and of the underlaying data. The systematic increase of the difference log gfW - log gfd for strong lines of high excitation potential is noticeable. Title: Some Photospheric Characteristics of the Sun as a Star Authors: Gurtovenko, E. A. Bibcode: 1982ASSL...96...99G Altcode: 1982spls.meet...99G No abstract at ADS Title: On the establishment of internally consistent solar scales of oscillator strengths and abundances of chemical elements. I. Oscillator strengths for 865 FeI lines iron abundance. Authors: Gurtovenko, E. A.; Kostik, R. I. Bibcode: 1981A&AS...46..239G Altcode: A method is developed for the establishment of internally consistent scales for solar abundances and oscillator strengths and used to deduce the solar iron abundance and the oscillator strengths for 865 Fe I lines. The method involves the calculation of L, defined as the product of the abundance with the oscillator strength, which can be inferred from the line profiles, equivalent widths, central intensities and the entire Fraunhofer spectrum of the specific chemical element. In the iron study, abundance and oscillator strengths are derived from unblended central intensities of lines in the region 4000-8000 A taking into account the influence of macroturbulence velocities. An average iron abundance of 7.525 + or - 0.007 is obtained from 266 weak and moderately strong lines appearing in the oscillator strength scale of May et al. (1974). The obtained abundance was then used to calculate the oscillation strengths of all 612 weak and moderate Fe I lines and the remaining strong lines to within + or - 0.035 dex. Title: On the Establishment of Internally Consistent Solar Scales of Oscillator Strengths and Abundances of Chemical Elements - Part Two - on the Errors of the Oscillator Strengths of FEI Lines in the Kurucz Authors: Gurtovenko, E. A.; Kostik, R. I. Bibcode: 1981A&A...101..132G Altcode: It is shown that the errors on the oscillator strengths of the Kurucz-Peytremann gf-scale depend in a regular way upon the excitation potential and gf-value. Oscillator strengths with small values of gf and large excitation potentials are underestimated, and vice versa. Especially strong underestimations (by ≍2 orders of magnitude) of the oscillator strengths take place for the lines with excitation potentials EPL > 4 eV and oscillator strengths log gf < -4.0. Title: The abundance of titanium in the solar photosphere Authors: Gurtovenko, E. A.; Fedorchenko, G. L.; Sheminova, V. A. Bibcode: 1981AAfz...43...59G Altcode: The abundance of titanium in the solar photosphere is determined from equivalent widths of 38 weak Fraunhofer lines of TiI. The oscillator strengths scale of Kurucz and Peytremann (1975) is used to obtain log(NTi/NH), + 12 = 4.95 + or - 0.05. The results are compared to other recent investigations, from which it is concluded that the oscillator strength system of Kurucz and Peytremann presents significant systematic errors, and must therefore be studied in detail, using a large number of lines for a wide range of equivalent widths. Title: The Empirical Determination of Damping Constants in the Solar Photosphere - Part One - Preliminary Results for FEI Lines Authors: Gurtovenko, E. A.; Kondrashova, N. N. Bibcode: 1980SoPh...68...17G Altcode: The evaluation of damping constants is discussed and the results of their empirical determination by various authors are listed in the Appendix. Title: On the Establishment of Internally Consistent Abundance-Oscillator Strength Scales Authors: Gurtovenko, E. A.; Kostik, R. I. Bibcode: 1980LNP...114..296G Altcode: 1980IAUCo..51..296G; 1980sttu.coll..296G No abstract at ADS Title: High-resolution solar spectroscopy with double-pass monochromators Authors: Gurtovenko, E. A. Bibcode: 1980AAfz...41...15G Altcode: The basic characteristics of double-pass monochromators for high-resolution solar spectroscopy are presented. Consideration is given to the determining influence of the intermediate slit on the wings of the apparatus function in the high-resolution registration of absorption line profiles. The double diffraction technique is described, and formulas for the apparatus function are presented. The principal errors of double-pass solar spectrometer are analyzed, and some suggestions concerning the adjustment of the device are given. Title: Solar Spectrographs Authors: Gurtovenko, E. A. Bibcode: 1980IGAFS..52...96G Altcode: No abstract at ADS Title: Determination of the damping constant from wings of strong Fraunhofer lines of the Liege solar spectrum atlas Authors: Kondrashova, N. N.; Gurtovenko, E. A. Bibcode: 1980AAfz...42...14K Altcode: No abstract at ADS Title: A complex study of the microturbulent velocity and damping constant in the solar photosphere. V - Preliminary results of a determination of the damping constant for Fe I lines Authors: Gurtovenko, E. A. Bibcode: 1979AAfz...39...37G Altcode: No abstract at ADS Title: Complex investigation of the 'microturbulent' velocity and attenuation constant in the solar photosphere. II - Determination of the abundance of iron from weak Fraunhofer lines of Fe I Authors: Gurtovenko, E. A.; Fedorchenko, G. L.; Sheminova, V. A. Bibcode: 1979AAfz...37...22G Altcode: In the present study, the abundance of iron in the photosphere is determined by comparing the observed and calculated equivalent line widths of 93 weak lines of Fe I. The HSRA photospheric model and the semiempirical gf values, tabulated by Kurucz and Peytremann (1975) are used in the calculations. A mean value of 7.82 plus or minus 0.05 is obtained for the abundance of iron. Title: Complex investigation of the 'microturbulent' velocity and damping constant in the solar photosphere. I - Introductory review Authors: Gurtovenko, E. A. Bibcode: 1979AAfz...37...12G Altcode: In the present paper, one-component (homogeneous) photospheric models are applied to the analysis of the microturbulent velocity and attenuation constant, each of which has a pronounced effect on the Fraunhofer line profiles and equivalent line widths. A close relationship between the microturbulence and attenuation constant is established. It is recommended to determine the value of microturbulence solely from the equivalent absorption line widths. Title: Double-diffraction monochromator of the Kiev-Golosseevo Observatory with a digital system for automation of observations and solar-spectrum processing Authors: Gurtovenko, E. A.; Kostyk, R. I. Bibcode: 1979AAfz...39...88G Altcode: No abstract at ADS Title: A complex study of the microturbulent velocity and damping constant in the solar photosphere. IV - an error study of the method of damping constant determination Authors: Gurtovenko, E. A.; Bondarenko, N. F. Bibcode: 1979AAfz...39...31G Altcode: No abstract at ADS Title: Combined study of the 'microturbulent' velocity and damping parameter in the solar photosphere. III - Determination of 'microturbulent' velocity from equivalent widths of Fe I lines Authors: Sheminova, V. A.; Gurtovenko, E. A. Bibcode: 1979AAfz...38...29S Altcode: No abstract at ADS Title: Comparison of Effective Depths of Fraunhofer Line Formation Calculated by Various Methods Authors: Gurtovenko, E. A.; Ratnikova-Sheminova, V. A. Bibcode: 1978SoPh...58..241G Altcode: The effective depths of formation of some typical Fraunhofer lines, calculated by the methods suggested by Gurtovenko et al. (1974), Beckers and Milkey (1975), and Makita (1977) are compared. Title: The effective depths of formation of weak Fraunhofer lines. I. Authors: Sheminova, V. A.; Gurtovenko, E. A. Bibcode: 1978AAfz...36...21S Altcode: Previous work on the determination of effective formation depths of weak Fraunhofer lines is reviewed. It is shown that the effective depths of weak lines computed from the Unsoeld-Pecker contribution function correspond to the depths at which fluctuations in the parameters that determine the line absorption factor have the greatest effect on variations in the observed profile of an absorption line. Formulas are given for calculating the effective formation depths of weak lines of various atoms and ions in the solar photosphere. Numerical results are presented for C I, N I, O I, Mg I and II, Si I and II, S I, Ca I and II, Sc I and II, Ti I and II, V I, Cr I and II, Fe I and II, Co I, Ni I, and Zn I and II. Title: Comparison of the profiles of weak Fraunhofer lines with the profile of the absorption coefficient. Authors: Gurtovenko, E. A.; Ratnikova, V. A. Bibcode: 1977AAfz...32....3G Altcode: Optical and geometric depths relative to 5000 A are calculated for three Fe I lines with the same excitation potential and different intensities: 6097 A (central intensity of 2.9%), 6392 A (central intensity of 18.8%), and 6240 A (central intensity of 50.4%). The results show that the depths at which the absorption-coefficient profile is close to the line profile are not greater than the limits of the layer determining the main region of absorption-line formation for lines with central depressions of less than 25% to 30%. Title: Study of amplitude of photospheric velocity field based on weak Fraunhofer lines of metals Authors: Gurtovenko, E. A. Bibcode: 1976SvA....19..488G Altcode: No abstract at ADS Title: The general photospheric velocity field. Authors: Gurtovenko, E. A. Bibcode: 1976AAfz...28...93G Altcode: The radial and tangential components of the general photospheric velocity field obtained by a variety of authors are compared. Fairly good correlation between results obtained by different methods from different observational material was found. A sharp growth of both components with increasing depth was found in the layers of the photosphere in which the absorption lines used in the investigation are formed. Expressions governing the change of the radial and tangential components with depth are derived on the basis of the results of averaging the weighted data reported by the different authors considered. Title: Non-thermal broadening of weak lines Authors: Gurtovenko, E. A.; de Jager, C.; Lindenbergh, A.; Rutten, R. J. Bibcode: 1976pmas.conf..331G Altcode: No abstract at ADS Title: Study of microturbulence from equivalent widths of moderate and moderately strong Fe I lines. Authors: Gurtovenko, E. A.; Ratnikova, V. A. Bibcode: 1976AAfz...30...14G Altcode: Equivalent widths of 25 weak and moderately strong Fe I Fraunhofer lines are analyzed using data from center-limb observations of the solar disk. An iron abundance with a logarithm of 7.04 is derived from the weak lines. Microturbulent velocity fields are investigated by employing the abundance values derived from moderately strong lines. A model of quasi-isotropic microturbulent velocity smoothly increasing with height from 0.6 km/s to 1.5 km/s (mean value, 1.1 km/s) over the depth range between 100 and 600 km is obtained for a specified photospheric model. It is concluded that microturbulent velocity can be determined only by analyzing absolute values of equivalent line widths and that the microturbulent-velocity model can be improved by analyzing lines formed at different depths. Title: The Total Photospheric Motion Field Authors: Gurtovenko, E. A. Bibcode: 1975SoPh...45...25G Altcode: Brief consideration is given to the conception of the total photospheric motion field. A synthesis of the most thorough investigations is made and the radial (Vrad) and tangential (Vtg) components of the velocity amplitude of the total photospheric motion field are deduced. At depth logτ5 = −3.0 Vrad and Vtg have average values of 1.2 and 1.7 km s−1 respectively. They increase smoothly with depth and reach their maximum values of Vrad=3.0, Vtg=3.4 km s−1 at depths logτ5= −0.2 and logτ5 = +0.4 respectively. In the deep photospheric layers both components seem to decrease with depth. Title: Study of amplitude of photospheric velocity field based on weak Fraunhofer lines of metals Authors: Gurtovenko, E. A. Bibcode: 1975AZh....52..804G Altcode: No abstract at ADS Title: Supplementary Remarks to `On the Average Depth of Formation of Weak Fraunhofer Lines' by E. Gurtovenko, V. Ratnikova, and C. de Jager Authors: Gurtovenko, E.; Ratnikova, V.; de Jager, C. Bibcode: 1975SoPh...42...43G Altcode: No abstract at ADS Title: Dependence of the formation depth of the weak Fraunhofer lines on atomic parameters Authors: Gurtovenko, E. A.; Ratnikova, V. A. Bibcode: 1975SvA....18..609G Altcode: Using an electronic digital computer, the average depth of the formation of weak Fraunhofer lines is calculated. A dependence of these depths on the lower-level excitation potential is evident. The average optical depth of the formation of weak absorption lines is determined mainly by the excitation potential of the lower level. The larger the excitation potential, the deeper is the formation of the absorption band. The average depths depend also on such factors as the ionization potentials of the neutral atom and iron, and on the partition functions. The joint effect of these parameters can be different for lines of various atoms and ions. A graph for some atoms and ions showing the dependences of the average optical depth on the excitation potentials is included. Title: The center-to-limb change of profiles of weak Fraunhofer lines. V. The radial and tangential components of the amplitude of the photospheric velocity field. Authors: Gurtovenko, E. A. Bibcode: 1975AAfz...27...67G Altcode: No abstract at ADS Title: Centre-to-limb change of the profiles of weak Fraunhofer lines. IV. Interpretation of the width of various lines in the solar disc centre. Authors: Gurtovenko, E. A. Bibcode: 1975AAfz...26...78G Altcode: No abstract at ADS Title: Profiles of selected Fraunhofer lines for various center-limb positions on the solar disk Authors: Gurtovenko, E. A.; Kostyk, R. I.; Orlova, T. V.; Troian, V. I.; Fedorchenko, G. L. Bibcode: 1975KiIND....Q....G Altcode: The profiles of 98 Fraunhofer lines are tabulated for five positions (cos theta equals 1.00, 0.80, 0.60, 0.44, and 0.28) on the disk of the quiet sun. The data are based primarily on observations in the wavelength range 5700 to 6400 A made with a double solar spectrometer. Title: Variation in the centre-limb profiles of weak Fraunhofer lines 2 asymmetry and line widths Authors: Gurtovenko, E. A. Bibcode: 1974STIN...7528996G Altcode: The observations were performed using a double-solar monochromator. The asymmetry of very weak lines was found to be highly varied, which may be associated with the superfine structure. Results are in accord with the theoretical interpretation of the asymmetry of traveling sonic waves. Observations of the same lines on different dates indicate a possible change in asymmetry with time. The turbulence velocities calculated from the widths of certain elements exhibit considerable diversity. The lines of the light elements S, Si, and N appear to be very wide. The effect of superfine and isotopic structure is shown to change to a marked degree the form and width of the profiles of many Fraunhofer lines. Title: Dependence of the formation depth of the weak Fraunhofer lines on atomic parameters Authors: Gurtovenko, E. A.; Ratnikova, V. A. Bibcode: 1974AZh....51.1032G Altcode: Using an electronic digital computer, the average depth of the formation of weak Fraunhofer lines is calculated. A dependence of these depths on the lower-level excitation potential is evident. The average optical depth of the formation of weak absorption lines is determined mainly by the excitation potential of the lower level. The larger the excitation potential, the deeper is the formation of the absorption band. The average depths depend also on such factors as the ionization potentials of the neutral atom and iron, and on the partition functions. The joint effect of these parameters can be different for lines of various atoms and ions. A graph for some atoms and ions showing the dependences of the average optical depth on the excitation potentials is included. Title: On the Average Optical Depth of Formation of Weak Fraunhofer Lines Authors: Gurtovenko, E.; Ratnikova, V.; De Jager, C. Bibcode: 1974SoPh...37...43G Altcode: Methods for the determination of the average optical depth of formation of weak Fraunhofer lines are compared, and their relative merits are discussed. Distinction should be made between the region of origin of the emergent radiation, and of the line depression. For weak or fairly weak lines the average optical depth of formation of the line depression is the relevant quantity; it should be determined by using a computational scheme based on the classical weighting functions of line formation; other methods give physically unsignificant or conflicting results. Title: The Determination of the Velocity Amplitude of the Total Photospheric Motion Field. I: The Use of the Weak and Moderately Weak Lines Authors: Kondrashova, N. N.; Gurtovenko, E. A. Bibcode: 1974SoPh...34..291K Altcode: By the analysis of the profiles of 20 weak lines observed at five centre-to-limb positions on the solar disk, radial and tangential components of the velocity amplitude of the photospheric motion field are derived in the range of optical depth - 3.0 ⩽ lgτ5 ⩽ +0.5. Title: Empirical analysis of deviations from LTE in moderate Fraunhofer lines. Authors: Gurtovenko, E. A.; Troian, V. I.; Fedorchenko, G. L. Bibcode: 1974AAfz...23...69G Altcode: A method is developed for empirically determining the line source function by means of studying multiplet pairs in center-to-limb observations of the solar disk. The method enables the line source function to be compared with the continuum source function in a given region of optical depth. The ratio of continuum source function to line source function does not exceed 1.2. Title: Change in Center-Line Profiles of Faint Fraunhofer Lines. I. Authors: Gurtovenko, E. A.; Kondrashova, N. N. Bibcode: 1973aars.conf..117G Altcode: No abstract at ADS Title: Determining Optical Depth in Different Parts of the Fraunhofer Line Contour Authors: Gurtovenko, E. A. Bibcode: 1973aars.conf..111G Altcode: No abstract at ADS Title: A change in centre-limb profiles of faint Fraunhofer lines. III. Profile shapes and velocity field. Authors: Gurtovenko, E. A. Bibcode: 1973AAfz...19...35G Altcode: No abstract at ADS Title: On physical conditions in the corona from spectral observations of the solar eclipse on March 7, 1970. Authors: Gurtovenko, E. A.; Alikayeva, K. V. Bibcode: 1972AAfz...15...55G Altcode: No abstract at ADS Title: Centre-to-limb change of faint Fraunhofer line profiles. II. Asymmetry and width of lines. Authors: Gurtovenko, E. A. Bibcode: 1972AAfz...16...77G Altcode: No abstract at ADS Title: On the empirical determination of the source function. Authors: Gurtovenko, E. A.; Fedorchenko, G. L. Bibcode: 1972AAfz...16...61G Altcode: No abstract at ADS Title: The Physical Conditions in Inner Corona Derived from Spectral Data of the Solar Eclipse on 7 March, 1970 (Papers presented at the Proceedings of the International Symposium on the 1970 Solar Eclipse, held in Seattle, U. S. A. , 18-21 June, 1971.) Authors: Gurtovenko, E. A.; Alikayeva, K. V. Bibcode: 1971SoPh...21..325G Altcode: The spectrum of the solar corona obtained during the eclipse of 7 March, 1970 has been studied. From the analysis of the line halfwidths it is concluded that the emission of coronal lines of various groups arises in different volumes of the corona. The lines λ5303 and λ4231 are analyzed in detail and by the use of the equations of excitation and ionization balance. The distribution of electron temperature Te and density ne vs height in the solar corona has been found. The usually adopted ne and Te are noticeably less than those values obtained in present analysis. This discrepancy may be due to the fact that the considered area of the corona seems to be in an unusual condition. Title: The Use of the Goldberg-Unno Method for the Investigation of Small-Scale Photosphere Motions Authors: Gurtovenko, E.; Troyan, V. Bibcode: 1971SoPh...20..264G Altcode: The Goldberg-Unno method is analysed. Accounting for the instrumental profile correction reduces the derived microturbulent velocities only slightly. A similar effect may be caused by an unresolved macroturbulence. The method of accounting for the damping effect is considered. The correction for the influence of the damping effect does not change substantially the general trend of the variation of ξt with τ0. The microturbulent velocity ξt is reduced appreciably. Title: Effect of Macroturbulence on Fraunhofer Line Profiles. Authors: Gurtovenko, É. A.; Ratnikova, V. A. Bibcode: 1971SvA....14..845G Altcode: No abstract at ADS Title: On the Problem of the Flare-Like Emission in Sodium Lines Authors: Gurtovenko, E. A. Bibcode: 1971SoPh...16..413G Altcode: Unusual and intense emission in the D1, D2 lines has been registered photoelectrically in an undisturbed region near the center of the solar disk on 28 July, 1966. Various aspects of the possibility that the emission might originate in either artificial or natural comets by processes of resonance scattering or flu orescence have been analyzed. It is shown that the observed emission can only be located on the solar surface. Some aspects of the problem are discussed briefly. Title: Effect of Macroturbulence on Fraunhofer Line Profiles. Authors: Gurtovenko, É. A.; Ratnikova, V. A. Bibcode: 1970AZh....47.1053G Altcode: No abstract at ADS Title: Determining Optical Depth in Different Parts of the Fraunhofer Line Contour Authors: Gurtovenko, E. A. Bibcode: 1970asas.book..111G Altcode: No abstract at ADS Title: Spectral observations of the chromosphere and corona during the total solar eclipse on March 7, 1970. Authors: Gurtovenko, E. A.; Skorik, K. E. Bibcode: 1970ATsir.580....1G Altcode: No abstract at ADS Title: Change in Center-Line Profiles of Faint Fraunhofer Lines. I. Authors: Gurtovenko, E. A.; Kondrashova, N. N. Bibcode: 1970asas.book..117G Altcode: No abstract at ADS Title: Center-to-limb variation of faint Fraunhofer lines. I. Authors: Gurtovenko, E. A.; Kondrashova, N. N. Bibcode: 1970AAfz....9...93G Altcode: No abstract at ADS Title: On the determination of optical depth for different parts of Fraunhofer profiles. Authors: Gurtovenko, E. A. Bibcode: 1970AAfz....9...89G Altcode: No abstract at ADS Title: The Use of a Laser Beam for Investigating the Instrumental Profile of a Double-Pass Solar Spectrograph Authors: Gurtovenko, E. A.; Fedorenko, L. U. Bibcode: 1969SoPh....6..465G Altcode: Some peculiarities of the use of a laser for the determination of the instrumental profile of the high-resolution spectrograph have been described. The results of the investigation of the instrumental profile of the Kiev-Golosejevo double-pass solar spectrograph are presented in graphs. Title: Active prominences of 9 and 11 July 1966. Authors: Gurtovenko, E. A.; Morozhenko, N. N.; Rakhubovsky, A. S. Bibcode: 1969AIQSY...3...96G Altcode: No abstract at ADS Title: The horizontal solar telescope ATSU-5 with a double diffraction spectrograph. Authors: Gurtovenko, E. A. Bibcode: 1969AAfz....8...77G Altcode: No abstract at ADS Title: On the density of Na in comet Ikeya-Seki (1965f). Authors: Gurtovenko, E. A. Bibcode: 1969AAfz....4..155G Altcode: No abstract at ADS Title: On the influence of the width of the intermediate slit of a double monochromator on the profiles of the Fraunhofer lines. Authors: Gurtovenko, E. A. Bibcode: 1969BSolD1969...91G Altcode: No abstract at ADS Title: Study of the turbulence in the solar photosphere from the Ti I-line profiles. Authors: Gurtovenko, E. A.; Troyan, V. I. Bibcode: 1969AAfz....8...85G Altcode: No abstract at ADS Title: Solar Physics at the Main Astronomical Observatory of the Ukrainian Academy of Sciences Authors: Gurtovenko, E. A. Bibcode: 1968SoPh....4..108G Altcode: No abstract at ADS Title: A Peculiar Sodium 'Flare' on the Sun Authors: Gurtovenko, E. A. Bibcode: 1967SoPh....1..389G Altcode: A peculiar brightening was observed near the centre of the D2 line of NaI on July 28, 1966, in a position where no activity could be seen in the Hα line but where a new important active region formed during the next rotation of the sun. The brightening, first observed at 06:30 UT, progressively faded and disappeared before 07:10 UT. Title: Computer Correction of Line Profiles for Instrumental Error. Authors: Gurtovenko, É. A. Bibcode: 1966SvA....10..520G Altcode: No abstract at ADS Title: Computer Correction of Line Profiles for Instrumental Error. Authors: Gurtovenko, É. A. Bibcode: 1966AZh....43..659G Altcode: No abstract at ADS Title: Three-Color Colorimetry of the Integral Brightness of Mars, Based on 1956 Observations. Authors: Gurtovenko, E. A.; Gordeladze, Sh. G. Bibcode: 1957SvA.....1..926G Altcode: No abstract at ADS Title: Three-Color Colorimetry of the Integral Brightness of Mars, Based on 1956 Observations. Authors: Gurtovenko, E. A.; Gordeladze, Sh. G. Bibcode: 1957AZh....34..959G Altcode: No abstract at ADS