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arXiv · 1410.7275

The impact of nuclear masses near $N=82$ on $r$-process abundances

M. Mumpower·D. -L. Fang·R. Surman·M. Beard·A. Aprahamian
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Abstract

We have performed for the first time a complete $r$-process mass sensitivity study in the $N=82$ region. We take into account how an uncertainty in a single nuclear mass propagates to influence important quantities of neighboring nuclei, including Q-values and reaction rates. We demonstrate that nuclear mass uncertainties of $\pm0.5$ MeV in the $N=82$ region result in up to an order of magnitude local change in $r$-process abundance predictions. We identify key nuclei in the study whose mass has a substantial impact on final $r$-process abundances and could be measured at future radioactive beam facilities.

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M. Mumpower, D. -L. Fang, R. Surman, M. Beard, A. Aprahamian. 2014-10-27. The impact of nuclear masses near $N=82$ on $r$-process abundances. https://doi.org/10.22323/1.204.0018

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