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arXiv · 1802.05837

Sensitivity to neutron captures and beta-decays of the enhanced s-process in rotating massive stars at low metallicities

N. Nishimura·R. Hirschi·T. Rauscher
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Abstract

The s-process in massive stars, producing nuclei up to $A\approx 90$, has a different behaviour at low metallicity if stellar rotation is significant. This enhanced s-process is distinct from the s-process in massive stars around solar metallicity, and details of the nucleosynthesis are poorly known. We investigated nuclear physics uncertainties in the enhanced s-process in metal-poor stars within a Monte-Carlo framework. We applied temperature-dependent uncertainties of reaction rates, distinguishing contributions from the ground state and from excited states. We found that the final abundance of several isotopes shows uncertainties larger than a factor of 2, mostly due to the neutron capture uncertainties. A few nuclei around branching points are affected by uncertainties in the $\beta$-decay.

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N. Nishimura, R. Hirschi, T. Rauscher. 2018-02-16. Sensitivity to neutron captures and beta-decays of the enhanced s-process in rotating massive stars at low metallicities. https://doi.org/10.1088/1742-6596/940/1/012051

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