Skip to main content

36 Result(s)

within Ya. V. Pavlenko Remove this filter

previous disabled Page of 2
and

  1. No Access

    Article

    Bands of NaH lines in Spectra of Late Type Stars

    The absorption of radiation by systems of NaH molecule bands in the atmospheres of late-type stars is modeled. Calculations of synthetic spectra with model atmosphere parameters, which corresponds to M stars, ...

    Yu. P. Lyubchyk, Ya. V. Pavlenko… in Kinematics and Physics of Celestial Bodies (2022)

  2. No Access

    Article

    Analysis of Actinium Abundances in the Atmosphere of Cepheid HIP13962

    Actinium is a radioactive element that has an isotope 227Ac with the longest half-life of 21.772(3) years. It is the third element in the actinoid group, in addition to thorium and uranium, the abundance of which...

    V. F. Gopka, A. V. Shavrina, V. A. Yushchenko… in Kinematics and Physics of Celestial Bodies (2022)

  3. No Access

    Article

    SiO Bands in the Infrared Spectra of Late-Type Stars

    Abstract—The importance of taking the SiO absorption in the infrared spectrum into account for spectral analysis of late-type stars is demonstrated. The lists of absorption lines of the fundamental SiO system cal...

    Ya. V. Pavlenko in Kinematics and Physics of Celestial Bodies (2019)

  4. No Access

    Article

    Actinium Abundance in the Atmospheres of Three Red Supergiants in the Magellanic Clouds

    The actinium abundance in the atmospheres of red supergiants PMMR23 and PMMR144 in the Small Magellanic Cloud and RM_1-667 in the Large Magellanic Cloud was estimated. The results of spectral observations with...

    V. F. Gopka, A. V. Shavrina, V. A. Yushchenko… in Kinematics and Physics of Celestial Bodies (2018)

  5. No Access

    Article

    Determination of abundances in the atmospheres of F-, G-, and K-dwarfs

    The algorithm of the determination of abundances in atmospheres of stars of spectral classes F, G, and K using fits to the observed spectral lines or selected parts of the blended lines is discussed. The techn...

    Ya. V. Pavlenko in Kinematics and Physics of Celestial Bodies (2017)

  6. No Access

    Article

    Atmospheric chemical composition of the peculiar carbon giant TU Gem

    The evolutionary status of the bright peculiar carbon giant TU Gemis fairly uncertain. The possibility that this is aCH star—aGalactic halo star with characteristic chemical-composition anomalies—is considered...

    L. A. Yakovina, G. A. Polinovskii, Ya. V. Pavlenko, M. K. Kuznetsov in Astronomy Reports (2017)

  7. No Access

    Article

    Collision-induced absorption of radiation in the atmospheres of late-type stars

    Problems associated with taking into account absorption induced by collisions between hydrogen and helium atoms, helium atoms and hydrogen molecules, and hydrogen molecules, resulting in the formation of short...

    Ya. V. Pavlenko in Astronomy Reports (2016)

  8. No Access

    Article

    The cool giant HD 77361—a super Li-rich star

    Super Li-rich stars form a very small and enigmatic group whose existence cannot be explained in terms of the standard stellar evolution theory. The goal of our study is to check the reality of this group of c...

    L. S. Lyubimkov, B. M. Kaminsky, V. G. Metlov, Ya. V. Pavlenko… in Astronomy Letters (2015)

  9. No Access

    Article

    Systems of VO and CaH molecule bands in spectra of spectral type M stars

    Radiation absorption by the CaH and VO molecular band systems in atmospheres of spectral type M dwarf stars is simulated. These bands form visible spectral details. The calculations involve detailed lists of l...

    Ya. V. Pavlenko, M. Schmidt in Kinematics and Physics of Celestial Bodies (2015)

  10. No Access

    Article

    Molecular bands in the spectra of M stars

    The profiles of the main molecular bands in the spectral-energy distributions (SEDs) of M stars have been calculated. The calculations of the individual band profiles were performed using the just-overlap**-...

    Ya. V. Pavlenko in Astronomy Reports (2014)

  11. No Access

    Article

    Analysis of the spectral energy distribution of the peculiar carbon giant TU gem

    The TU Gem star has long been known as a peculiar carbon giant of the Galaxy halo, but its classification as a CH star is still debated. We estimated the TU Gem atmosphere parameters through modeling its spect...

    G. O. Polinovskyi, L. A. Yakovina… in Kinematics and Physics of Celestial Bodies (2014)

  12. No Access

    Article

    Analysis of the spectral energy distributions of four cool R CrB stars near the brightness maximum

    The effective temperatures T eff and carbon and nitrogen abundances in the atmospheres of the cool R CrB stars ES Aql, SV Sge, Z UMi, and NSV 11154 have been determined by modeling their s...

    L. A. Yakovina, A. E. Rosenbush, Ya. V. Pavlenko, B. M. Kaminsky in Astronomy Reports (2013)

  13. No Access

    Article

    Simulation of energy distributions in optical and IR spectra of late-type M4–M6 dwarfs

    Spectral types (M4–M6), effective temperatures T ef (2700–2900 K), and free fall accelerations logg (4.0–4.5) are determined for five M dwarfs using their energy distributions in the spectral rang...

    M. K. Kuznetsov, Ya. V. Pavlenko… in Kinematics and Physics of Celestial Bodies (2012)

  14. No Access

    Article

    Physical parameters of the binary star CM draconis components

    Spectra of the eclipsing binary star CM Dra consisting of two M dwarfs are discussed in detail. High-resolution echelle spectra (R = 47000) obtained using the 4.2 m William Hershel telescope are used. The tempera...

    M. K. Kuznetsov, Ya. V. Pavlenko, D. Pinfield… in Kinematics and Physics of Celestial Bodies (2012)

  15. No Access

    Article

    Atmospheric lithium abundances of the carbon giants AQ And, HK Lyr, UX Dra, and WZ Cas

    The LTE lithium abundances, logN (Li), have been determined for the atmospheres of the four carbon giants AQ And, HK Lyr, UX Dra, and WZ Cas, applying the synthetic-spectrum technique to the LiI λ670.8 nm resonan...

    L. A. Yakovina, Ya. V. Pavlenko in Astronomy Reports (2012)

  16. No Access

    Article

    Lithium abundances in atmospheres of carbon stars estimated with the help of modern lists of spectral lines

    We determine lithium abundances in atmospheres of three carbon stars from synthetic spectrum fitting in the λλ 668–674 nm range using the Li I λ 670.8 nm resonance doublet. To produce synthetic spectra, we use...

    L. A. Yakovina, Ya. V. Pavlenko, K. Abia… in Kinematics and Physics of Celestial Bodies (2011)

  17. No Access

    Article

    Formation depths of lithium resonance absorption lines in the atmospheres of late-type stars and brown dwarfs

    A numerical technique for determining absorption line formation depths in the atmospheres of late-type stars and substellar-mass subdwarfs is proposed. The technique is based on estimating individual absorptio...

    Ya. V. Pavlenko in Kinematics and Physics of Celestial Bodies (2010)

  18. No Access

    Article

    Some properties of the He-w star HD 35502

    This is a preliminary study of the star HD 35502. Its magnetic field has been measured in different phases of its period. Preliminary values of the magnetic field parameters have been obtained based on a centr...

    Yu. V. Glagolevskij, G. A. Chountonov, A. V. Shavrina, Ya. V. Pavlenko in Astrophysics (2010)

  19. No Access

    Article

    Model atmospheres of carbon giants with high carbon abundance

    We calculated 240 model atmospheres of carbon giants with high carbon abundance (2800 K ≤ T eff ≤ 3400 K, 0.06 ≤ log(C/O) ≤ 2.7). This set of models was used for modelling of the energy di...

    Ya. V. Pavlenko, L. A. Yakovina in Kinematics and Physics of Celestial Bodies (2009)

  20. No Access

    Article

    Spot system and stratification of some chemical elements in the atmosphere of He-weak star HD 21699

    Surface helium and silicon distribution of a He-weak CP star HD21699 was examined using the spectra obtained at different phases of the star’s rotational period. The abundance of helium over the whole surface ...

    Yu. V. Glagolevskij, A. V. Shavrina, J. Sylvestre… in Astrophysical Bulletin (2009)

previous disabled Page of 2