Symmetry energy: nuclear masses and neutron stars

TL;DR

This paper presents advanced nuclear mass models based on Skyrme forces, linking nuclear symmetry energy to neutron star properties, and finds a symmetry coefficient J of about 30 MeV consistent with various measurements.

Contribution

The paper introduces new Hartree-Fock-Bogoliubov nuclear mass models fitted to experimental data, integrating ab initio neutron matter equations of state for neutron star modeling.

Findings

Symmetry coefficient J ≈ 30 MeV supported by nuclear and neutron star data.

Models accurately reproduce nuclear masses with a deviation of 0.549 MeV.

Predicted neutron star properties align with observational constraints.

Abstract

We describe the main features of our most recent Hartree-Fock-Bogoliubov nuclear mass models, based on 16-parameter generalized Skyrme forces. They have been fitted to the data of the 2012 Atomic Mass Evaluation, and favour a value of 30 MeV for the symmetry coefficient J, the corresponding root-mean square deviation being 0.549 MeV. We find that this conclusion is compatible with measurements of neutron-skin thickness. By constraining the underlying interactions to fit various equations of state of neutron matter calculated {\it ab initio} our models are well adapted to a realistic and unified treatment of all regions of neutron stars. We use our models to calculate the composition, the equation of state, the mass-radius relation and the maximum mass. Comparison with observations of neutron stars again favours a value of J = 30 MeV.