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arXiv · 2102.05891

Contribution of collapsars, supernovae, and neutron star mergers to the evolution of r-process elements in the Galaxy

Yuta Yamazaki·Toshitaka Kajino·Grant J. Mathews·Xiaodong Tang·Jianrong Shi·Michael A. Famiano
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Abstract

We study the evolution of rapid neutron-capture process (r-process) isotopes in the Galaxy. We analyze relative contributions from core collapse supernovae (CCSNe), neutron star mergers (NSMs) and collapsars under a range of astrophysical conditions and nuclear input data. Although the r-process in each of these sites can lead to similar (or differing) isotopic abundances, our simulations reveal that the early contribution of r-process material to the Galaxy was dominated by CCSNe and collapsar r-process nucleosynthesis, while the NSM contribution is unavoidably delayed even under the assumption of the shortest possible minimum merger time.

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Yuta Yamazaki, Toshitaka Kajino, Grant J. Mathews, Xiaodong Tang, Jianrong Shi, Michael A. Famiano. 2021-02-11. Contribution of collapsars, supernovae, and neutron star mergers to the evolution of r-process elements in the Galaxy. https://arxiv.org/abs/2102.05891

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