Journal
ASTROPHYSICAL JOURNAL
Volume 650, Issue 2, Pages L127-L130Publisher
IOP PUBLISHING LTD
DOI: 10.1086/508878
Keywords
nuclear reactions, nucleosynthesis, abundances; stars : abundances; stars : AGB and post-AGB; stars : individual (CS 31062-050, LP 625-44); stars : Population II
Categories
Funding
- STFC [PP/D000920/1] Funding Source: UKRI
- Science and Technology Facilities Council [PP/D000920/1] Funding Source: researchfish
Ask authors/readers for more resources
We have investigated the abundances of heavy neutron-capture elements, including osmium ( Os) and iridium (Ir), in the two carbon-enhanced metal-poor (CEMP) subgiants CS 31062-050 and LP 625-44. CS 31062-050 is known to be a so-called CEMP-r/s star, which exhibits large excesses of s-process elements such as barium (Ba) and lead (Pb), as well as a significant enhancement of europium (Eu) that cannot be explained by conventional s-process production in asymptotic giant branch star models. Our analysis of the high-resolution spectrum for this object has determined, for the first time, the abundances of Ir and Os, elements in the third peak of the r-process nucleosynthesis. They also exhibit significant excesses relative to the predictions of standard s-process calculations. These two elements are not detected in a similar quality spectrum of LP 625-44; the derived upper limits on their abundances are lower than the abundances in CS 31062-050. We compare the observed abundance patterns of neutron-capture elements, including Os and Ir, in these two stars with recent model calculations of the s-process, and we discuss possible interpretations.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available