English

Neutron-capture elements in the very metal-poor star HD122563

Astrophysics 2009-11-11 v1

Abstract

We obtained high resolution, high S/N spectroscopy for the very metal-poor star HD122563 with the Subaru Telescope High Dispersion Spectrograph. Previous studies have shown that this object has excesses of light neutron-capture elements, while its abundances of heavy ones are very low. In our spectrum covering 3070 - 4780 A of this object, 19 neutron-capture elements have been detected, including seven for the first time in this star (Nb, Mo, Ru, Pd, Ag, Pr, and Sm). Upper limits are given for five other elements including Th. The abundance pattern shows a gradually decreasing trend, as a function of atomic number, from Sr to Yb, which is quite different from those in stars with excesses of r-process elements. This abundance pattern of neutron-capture elements provides new strong constraints on the models of nucleosynthesis responsible for the very metal-poor stars with excesses of light neutron-capture elements but without enhancement of heavy ones.

Keywords

Cite

@article{arxiv.astro-ph/0602107,
  title  = {Neutron-capture elements in the very metal-poor star HD122563},
  author = {S. Honda and W. Aoki and Y. Ishimaru and S. Wanajo and S. G. Ryan},
  journal= {arXiv preprint arXiv:astro-ph/0602107},
  year   = {2009}
}

Comments

29 pages, 7 figures, Accepted for publication in ApJ