Carbon-Enhanced Metal-Poor (CEMP) stars
Abstract
A significant fraction of metal-poor stars have large over-abundances of carbon, and are called Carbon-Enhanced Metal-Poor (CEMP) stars. Most of CEMP stars also show excesses of heavy neutron-capture elements like Ba, indicating that their origin is the nucleosynthesis in AGB stars. Remaining CEMP stars that have Ba abundances as low as non-carbon-rich stars appear in the lowest metallicity range ([Fe/H]≲-2.5), and connections with the two most iron-deficient stars (so-called Hyper Metal-Poor stars) are suggested. Although the origins of the carbon-excesses in these objects have not been well identified, some objects suggest contributions of faint supernovae. Remaining problems on CEMP stars, such as the binary fraction, excess of r-process elements, are discussed.
- Publication:
-
Chemical Abundances in the Universe: Connecting First Stars to Planets
- Pub Date:
- March 2010
- DOI:
- 10.1017/S1743921310000311
- Bibcode:
- 2010IAUS..265..111A
- Keywords:
-
- stars:abundances;
- stars:AGB and post-AGB;
- stars:carbon;
- supernovae