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A VLT-UVES spectrscopic analysis of C-rich Fe-poor stars

T. Masseron·B. Plez·F. Primas·S. Van Eck·A. Jorissen
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Abstract

Large surveys of very metal-poor stars have revealed in recent years that a large fraction of these objects were carbon-rich, analogous to the more metal-rich CH-stars. The abundance peculiarities of CH-stars are commonly explained by mass-transfer from a more evolved companion. In an effort to better understand the origin and importance for Galactic evolution of Fe-poor, C-rich stars, we present abundances determined from high-resolution and high signal-to-noise spectra obtained with the UVES instrument attached to the ESO/VLT. Our analysis of carbon-enhanced objects includes both CH stars and more metal-poor objects, and we explore the link between the two classes. We also present preliminary results of our ongoing radial velocity monitoring.

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T. Masseron, B. Plez, F. Primas, S. Van Eck, A. Jorissen. 2006-01-11. A VLT-UVES spectrscopic analysis of C-rich Fe-poor stars. https://arxiv.org/abs/astro-ph/0601253

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