Neutron-Capture Elements in the Double-Enhanced Star HE 1305-0007: a New s- and r-Process Paradigm
Abstract
The star HE 1305-0007 is a metal-poor double-enhanced star with metallicity [Fe/H] , which is just at the upper limit of the metallicity for the observed double-enhanced stars. Using a parametric model, we find that almost all s-elements were made in a single neutron exposure. This star should be a member of a post-common-envelope binary. After the s-process material has experienced only one neutron exposure in the nucleosynthesis region and is dredged-up to its envelope, the AGB evolution is terminated by the onset of common-envelope evolution. Based on the high radial-velocity of HE 1305-0007, we speculate that the star could be a runaway star from a binary system, in which the AIC event has occurred and produced the r-process elements.
Keywords
Cite
@article{arxiv.0704.0576,
title = {Neutron-Capture Elements in the Double-Enhanced Star HE 1305-0007: a New s- and r-Process Paradigm},
author = {Wen-Yuan Cui and D. N. Cui and Y. S. Du and B. Zhang},
journal= {arXiv preprint arXiv:0704.0576},
year = {2009}
}
Comments
4 pages, 3 figures, paper accepted for publication in Chinese Physics letters