Influence of nuclear mass uncertainties on radiative neutron-capture rates

Abstract

Neutron-capture rate plays a crucial role in the rapid neutron-capture process (r-process) and nuclear mass is one of the most important inputs for the estimations of neutron-capture rates. In this work, we employ ten nuclear mass models, including macroscopic, macroscopic-microscopic, and microscopic models, to calculate the radiative neutron-capture rates for the nuclei relevant to the r-process at various temperatures $T={10}^{5}--{10}^{10}\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. It is found that the differences in the predictions of neutron-capture rate using these mass models get larger when moving to the neutron-rich and superheavy regions, whereas they generally become smaller with the increase of temperature. Taking the nuclei on the $N=126$ r-process path as examples, we find that the uncertainties of neutron-capture rates at $T={10}^{9}\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ range from about one to four orders of magnitude. The influence of the experimental mass errors on neutron-capture rates is investigated as well.