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arXiv · 1201.4699

Chemical composition of AY Ceti: A flaring, spotted star with a white dwarf companion

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

The detailed chemical composition of the atmosphere AY Cet (HD 7672) is determined from a high-resolution spectrum in the optical region. The main atmospheric parameters and the abundances of 22 chemical elements, including key species such as 12C, 13C, N, and O, are determined. A differential line analysis gives T_eff=5080 K, log g=3.0, [Fe/H]=-0.33, [C/Fe]=-0.17, [N/Fe]=0.17, [O/Fe]=0.05, C/N=1.58, and 12C/13C=21. Despite the high chromospheric activity, the optical spectrum of AY Cet provides a chemical composition typical for first ascent giants after the first dredge-up.

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G. Tautvaišienė, G. Barisevičius, S. Berdyugina, I. Ilyin, Y. Chorniy. 2012-01-23. Chemical composition of AY Ceti: A flaring, spotted star with a white dwarf companion. https://doi.org/10.1002/asna.201111597

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