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The chemical composition of the rare J-type carbon stars

Carlos Abia·Jordi Isern
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Abstract

Abundances of lithium, heavy elements and carbon isotope ratios have been derived in 12 J-type galactic carbon stars. The abundance analysis shows that in these stars the abundances of s-process elements with respect to the metallicity are nearly solar. Tc is not present in most of them. The Rb abundances, obtained from the resonance 7800 Å RbI line, are surprisingly low, probably due to stroong non-LTE effects. Lithium and $^{13}$C are found to be enhanced in all the stars. These results are used to discuss the origin of J-stars.

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Carlos Abia, Jordi Isern. 1999-12-01. The chemical composition of the rare J-type carbon stars. https://arxiv.org/abs/astro-ph/9912025

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