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arXiv · 1105.0947

Chemical Composition of the RS CVn-type Star 29 Draconis

G. Barisevičius·G. Tautvaišienė·S. Berdyugina·Y. Chorniy·I. Ilyin
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Abstract

Photospheric parameters and chemical composition are determined for the single-lined chromospherically active RS CVn-type star 29 Draconis (HD 160538). From the high resolution spectra obtained on the Nordic Optical Telescope, abundances of 22 chemical elements, including the key elements such as 12C, 13C, N and O, were investigated. The differential line analysis with the MARCS model atmospheres gives Teff=4720 K, log g=2.5, Fe/H]=-0.20, [C/Fe]=-0.14, [N/Fe]=0.08, [O/Fe]=-0.04, C/N=2.40, 12C/13C=16. The low value of the 12C/13C ratio gives a hint that extra mixing processes in low-mass chromospherically active stars may start earlier than the theory of stellar evolution predicts.

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G. Barisevičius, G. Tautvaišienė, S. Berdyugina, Y. Chorniy, I. Ilyin. 2011-05-04. Chemical Composition of the RS CVn-type Star 29 Draconis. https://doi.org/10.1515/astro-2017-0419

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