Nuclear Potentials Relevant to the Symmetry Energy in Chiral Models

Abstract

We employ the extended Nambu-Jona-Lasinio (NJL), linear-σ models, and the density-dependent model with chiral limits to work out the mean fields and relevant properties of nuclear matter. To have the constraint from the data, we re-examine the Dirac optical potentials and symmetry potential based on the relativistic impulse approximation (RIA). Unlike the extended NJL and the density-dependent models with the chiral limit in terms of the vanishing scalar density, the extended linear-σ model with a sluggish changing scalar field loses the chiral limit at the high-density end. The various scalar fields can characterize the different Schrödinger-equivalent potentials and kinetic symmetry energy in the whole density region and the symmetry potential in the intermediate density region. The drop in the scalar field due to the chiral restoration results in a clear rise of the kinetic symmetry energy. The chiral limit in the models gives rise to the softening of the symmetry potential and thereof the symmetry energy at high densities.

Neutron star core-crust transition and the crustal moment of inertia in the nonlinear relativistic Hartree approximation*

“…( 22), gradually fail owing to an increase in and a decrease in , widening the separation between the results obtained from Eqs. ( 21) and (22). Interestingly, the required to reach the limit of % with the complete formula in Eq.…”