Impacts of nuclear-physics uncertainties in the s-process determined by Monte-Carlo variations [SSA]

http://arxiv.org/abs/1802.05836


The s-process, a production mechanism based on slow-neutron capture during stellar evolution, is the origin of about half the elements heavier than iron. Abundance predictions for s-process nucleosynthesis depend strongly on the relevant neutron-capture and $\beta$-decay rates, as well as on the details of the stellar model being considered. Here, we have used a Monte-Carlo approach to evaluate the nuclear uncertainty in s-process nucleosynthesis. We considered the helium burning of massive stars for the weak s-process and low-mass asymptotic-giant-branch stars for the main s-process. Our calculations include a realistic and general prescription for the temperature dependent uncertainty for the reaction cross sections. We find that the adopted uncertainty for (${\rm n},\gamma$) rates, tens of per cent on average, effects the production of s-process nuclei along the line of $\beta$-stability, and that the uncertainties in $\beta$-decay from excited state contributions, has the strongest impact on branching points.

Read this paper on arXiv…

N. Nishimura, G. Cescutti, R. Hirschi, et. al.
Mon, 19 Feb 18
12/41

Comments: 6 pages, 4 figures, 2 tables, the Proceedings of “the 2017 Symposium on Nuclear Data”; a supplementary article of arXiv:1701.00489