出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We present detailed abundance results concerning CEMP (Carbon Enhanced Metal-Poor) stars
and the various subclasses. Statistical arguments from radial velocity monitoring show that these
stars are all binaries and have mass transferred from a former AGB. Therefore these stars are
the direct witnesses of the nucleosynthesis production of the rst low and intermediate mass
stars. To put CEMP stars in context, our broad approach includes the study of 180 stars of
various metallicities (from solar down to [Fe/H]=-4), luminosity classes (dwarfs and giants), and
abundance patterns (C-rich and poor, Ba-rich and poor, etc.). With these data, we attempt to
isolate the effect of the intrinsic parameters on AGB nucleosynthesis such as metallicity, mass,
dilution, mass loss and neutron source. The abundance ratios suggest that the CEMP-s stars
were polluted by low-mass AGB stars, while the CEMP-r&s stars were polluted by intermediatemass
AGB stars. At the lowest metallicities, we propose that the s-process in AGB stars is very
inefcient, leading to the formation of CEMP-no stars.
