Study of The Abundance Patterns in The Metal-Poor Stellar Stream
arXiv:1209.5505 · doi:10.1017/pasa.2012.015
Abstract
The chemical abundances of the metal-poor stars in the stellar stream provide important information for setting constraints on models of neutron-capture processes. The study of these stars could give us a better understanding of r-process nucleosynthesis and chemical composition of the early Galaxy. Using the updated main r-process and weak r-process patterns, we fit abundances in the stellar stream stars. The weak r-process component coefficients are almost constant for the sample stars, including r-rich stars, which means that both weak r-process and Fe are produced as primary elements from SNeII and their yields have nearly a constant mass fraction. The difference between the stream stars and r-rich stars is obvious. For the stream stars, that the increase trend in the main r-process component coefficients as metallicity increases means the gradual increase in the production of main r-process elements relative to iron. This behavior implies that the masses of progenitors for the main r-process are smaller than those of the weak r-process. Furthermore, we find metal-poor stream star HD 237846 is a weak r-process star.
12 pages, 7 figures, accepted for publication in PASA
References in corpus (7)
- Near-UV Observations of HD221170: New Insights into the Nature of r-Process-Rich Stars
- Neutron-capture elements in the very metal-poor star HD122563
- Nucleosynthesis in the Early Galaxy
- Neutron-capture elements in the very metal-poor star HD88609: another st ar with excesses of light neutron-capture elements
- Halo Star Streams in the Solar Neighborhood
- Neutron-capture elements in the s- and r-process-rich stars: Constraints on neutron-capture nucleosynthesis processes
- A holistic abundance analysis of r-rich stars