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

TL;DR

This study assesses how uncertainties in nuclear reaction rates influence s-process nucleosynthesis in stars, highlighting neutron capture rate uncertainties as the primary source of abundance variations and proposing key reactions for future experimental refinement.

Contribution

It introduces a Monte Carlo-based method to quantify the impact of nuclear physics uncertainties on s-process nucleosynthesis in stars.

Findings

Neutron capture rate uncertainties dominate abundance variations.

Beta-decay rate uncertainties affect only a few nuclei near branchings.

Identifies key nuclear reactions for targeted experimental improvements.

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.