Zobrazeno 1 - 10
of 285
pro vyhledávání: '"Korotin, S. A."'
Autor:
Mishenina, T., Pignatari, M., Usenko, I., Soubiran, C., Thielemann, F. -K., Kniazev, A. Yu., Korotin, S. A., Gorbaneva, T.
The oldest stars in the Milky Way are metal-poor with [Fe/H] < -- 1.0, displaying peculiar elemental abundances compared to solar values. The relative variations in the chemical compositions among stars is also increasing with decreasing stellar meta
Externí odkaz:
http://arxiv.org/abs/2405.11234
The purpose of this work is to spectroscopically analyse the classical Cepheid V708 Car. A preliminary check of the spectrum of V708 Car showed that this is a lithium-rich supergiant. We also found that V708 Car has an unusual chemical composition in
Externí odkaz:
http://arxiv.org/abs/2402.13072
While looking for recently discovered distant Cepheids with an interesting chemical composition, we noticed one star (OGLE GD-CEP-1353) with extremely large equivalent widths of spectral lines of heavy elements. The aim of this work is to perform an
Externí odkaz:
http://arxiv.org/abs/2310.10381
We present chemical composition and fundamental parameters (the effective temperature, surface gravity and radius) for four sharp-lined A-type stars ${\gamma}$ Gem (HD 41705), o Peg (HD 214994), ${\theta}$ Vir (HD 114330) and ${\nu}$ Cap (HD 193432).
Externí odkaz:
http://arxiv.org/abs/2309.08384
We have searched for lines of the radioactive element technetium (Tc) in the spectrum of Przybylski's star (HD101065). The nuclei of this chemical element are formed in the slow process of capturing thermalized neutrons. The possible lines of Tc~I ar
Externí odkaz:
http://arxiv.org/abs/2308.04479
This study shows that the statistical equilibrium of Si II in the atmosphere of a B3 IV type star iota Her is extremely sensitive to a variation in photoionization cross-sections for the Si II levels. The difference in abundances derived from absorpt
Externí odkaz:
http://arxiv.org/abs/2204.01354
Abundance of beryllium in the Sun and stars: The role of non-local thermodynamic equilibrium effects
Autor:
Korotin, S., Kučinskas, A.
Publikováno v:
A&A 657, L11 (2022)
Earlier studies have suggested that deviations from the local thermodynamic equilibrium (LTE) play a minor role in the formation of Be II 313 nm resonance lines in solar and stellar atmospheres. Recent improvements in the atomic data allow a more com
Externí odkaz:
http://arxiv.org/abs/2201.00532
Publikováno v:
A&A 660, A46 (2022)
We determined abundances of Na and Zr in the atmospheres of 237 RGB stars in Galactic globular cluster (GGC) 47 Tuc (NGC 104), with a primary objective of investigating possible differences between the abundances of Zr in the first generation (1P) an
Externí odkaz:
http://arxiv.org/abs/2111.10838
Publikováno v:
A&A 656, A67 (2021)
Context. While most (if not all) Type I Galactic globular clusters (GGCs) are characterised by spreads in the abundances of light chemical elements (e.g. Li, N, O, Na, Mg, Al), it is not yet well established whether similar spreads may exist in s-pro
Externí odkaz:
http://arxiv.org/abs/2109.05586
A Rb deficiency by a factor two with respect to the Sun has been found in M dwarfs of solar metallicity. This deficiency is difficult to understand from both the observational and nucleosynthesis point of views. To test the reliability of this Rb def
Externí odkaz:
http://arxiv.org/abs/2102.02498