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arXiv · 1505.07789

The impact of individual nuclear masses on $r$-process abundances

M. R. Mumpower·R. Surman·D. -L. Fang·M. Beard·P. Moller·T. Kawano·A. Aprahamian
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Abstract

We have performed for the first time a comprehensive study of the sensitivity of $r$-process nucleosynthesis to individual nuclear masses across the chart of nuclides. Using the latest version (2012) of the Finite-Range Droplet Model, we consider mass variations of $\pm0.5$ MeV and propagate each mass change to all affected quantities, including $Q$-values, reaction rates, and branching ratios. We find such mass variations can result in up to an order of magnitude local change in the final abundance pattern produced in an $r$-process simulation. We identify key nuclei whose masses have a substantial impact on abundance predictions for hot, cold, and neutron star merger $r$-process scenarios and could be measured at future radioactive beam facilities.

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M. R. Mumpower, R. Surman, D. -L. Fang, M. Beard, P. Moller, T. Kawano, A. Aprahamian. 2015-05-28. The impact of individual nuclear masses on $r$-process abundances. https://doi.org/10.1103/physrevc.92.035807

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