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arXiv · 1708.01629

The s-process nucleosynthesis: impact of the uncertainties in the nuclear physics determined by Monte Carlo variations

G. Cescutti·N. Nishimura·R. Hirschi·T. Rauscher·J. W. den Hartogh·A. St. J. Murphy
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Abstract

We investigated the impact of uncertainties in neutron-capture and weak reactions (on heavy elements) on the s-process nucleosynthesis in low-mass stars and massive stars using a Monte-Carlo based approach. We performed extensive nuclear reaction network calculations that include newly evaluated temperature-dependent upper and lower limits for the individual reaction rates. We found beta-decay rate uncertainties affect only a few nuclei near s-process branchings, whereas most of the uncertainty in the final abundances is caused by uncertainties in the neutron capture rates. We suggest a list of uncertain rates as candidates for improved measurement by future experiments.

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G. Cescutti, N. Nishimura, R. Hirschi, T. Rauscher, J. W. den Hartogh, A. St. J. Murphy. 2017-08-02. The s-process nucleosynthesis: impact of the uncertainties in the nuclear physics determined by Monte Carlo variations. https://arxiv.org/abs/1708.01629

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