Speaker
Description
This study focuses on constructing equations of state based on relativistic mean-field (RMF) theory to investigate the impact of remaining uncertainties in nuclear matter properties. We examine two key factors: the nucleon effective mass and the presence of multineutron states in non-uniform nuclear matter.
Our results demonstrate that a larger nucleon effective mass within the RMF enhances the abundance of heavy nuclei in neutron-rich environments, primarily due to variations in the density dependence of the symmetry energy. Regarding multineutron states, we evaluate the effects of incorporating dineutron and tetraneutron states. In highly neutron-rich environments, the fraction of the multineutron states becomes dominant at high densities, significantly reducing the fraction of unbound neutrons.
Furthermore, the formation of dineutrons and tetraneutrons increases the fractions of unbound protons and heavy nuclei with larger mass and proton numbers.
Our findings suggest that an increased effective mass in RMF formalism and the presence of multineutron states lead to stronger neutrino trapping and extend the duration of neutrino emission from proto-neutron stars. In particular, the increase in free protons can enhance neutrino emission rates, potentially improving the efficiency of neutrino heating.