Barium and Tc-poor S stars: Binary masqueraders among carbon stars

A. Jorissen; S. Van Eck

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arXiv · astro-ph/9708052

Barium and Tc-poor S stars: Binary masqueraders among carbon stars

A. Jorissen·S. Van Eck

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Abstract

The current understanding of the origin of barium and S stars is reviewed, based on new orbital elements and binary frequencies. The following questions are addressed: (i) Is binarity a necessary condition to produce a barium star? (ii) What is the mass transfer mode (wind accretion or RLOF?) responsible for their formation? (iii) Do barium stars form as dwarfs or as giants? (iv) Do barium stars evolve into Tc-poor S stars? (v) What is the relative frequency of Tc-rich and Tc-poor S stars?

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A. Jorissen, S. Van Eck. 1997-08-06. Barium and Tc-poor S stars: Binary masqueraders among carbon stars. https://arxiv.org/abs/astro-ph/9708052

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