Abundances in extremely metal-poor stars: comparison of the trends of abundance ratios in giants and turnoff stars
Abstract
We show that in a sample of Extremely Metal-Poor (EMP) giants (<[Fe/H]>=−3.1) all the stars with a luminosity higher than logL/L⊙ ≈ 2.6 present the characteristics of a mixing of the surface with the H-burning layer: low abundance of carbon and high abundance of nitrogen. In these "mixed stars" the lithium abundance and the ratio 12C/13C are very low. Some of these stars are also Na or/and Al rich.
- Publication:
-
Convection in Astrophysics
- Pub Date:
- May 2007
- DOI:
- 10.1017/S1743921307000555
- Bibcode:
- 2007IAUS..239..280S
- Keywords:
-
- Stars: abundances;
- stars: atmospheres;
- stars: Population II;
- subdwarfs;
- supernovae;
- nucleosynthesis