Correlations between nuclear landscape boundaries and neutron-rich r-process abundances

Abstract

Motivated by the newly observed ${}^{39}$Na in experiments, systematic calculations of global nuclear binding energies with seven Skyrme forces are performed. We demonstrate the strong correlation between the two-neutron separation energies ($S_{2n}$) of ${}^{39}$Na and the total number of bound nuclei of the whole nuclear landscape. Furthermore, with calculated nuclear masses, we perform astrophysical rapid-neutron capture process ($r$-process) simulations by using nuclear reaction code TALYS and nuclear reaction network code SkyNet. $r$-process abundances from ejecta of neutron star mergers and core-collapse supernova are compared. Prominent covariance correlations between nuclear landscape boundaries and neutron-rich $r$-process abundances before the third peak are shown. This study highlights the needs for further experimental studies of drip-line nuclei around ${}^{39}$Na for better constraints on nuclear landscape boundaries and $r$-process.

Comments: 7 pages, 5 figures