Orateur
Description
We investigate outer crust compositions for a wide range of pressures (densities) and magnetic-field strengths, adopting the latest experimental masses (AME2020) supplemented with various theoretical mass models. By exploring the optimal composition of nuclei in the entire nuclear chart, we find emergence of neutron-rich heavy nuclei, which are much heavier than previously thought (that was at most $Z\approx50$), mainly because of the increasing electron density with the magnetic field strength, which allows nuclei to exist at higher densities without leakage of neutrons. We point out a clear manifestation of neutron magic numbers, e.g. $N=50, 82, 126$, as well as $184$, and possibly those around the next spherical magic number $N\approx 258$. Furthermore, surprisingly enough, for $B\geq4\times10^{18}$ G, we find that superheavy nuclei with $Z>110$, including the unknown element $119$, naturally emerge as optimal compositions that minimize the Gibbs energy. In this talk, we will explain the aforementioned findings and discuss possible consequences.
