Isovector channel of quark-meson-coupling model and its effect on symmetry energy

TL;DR

This paper investigates how the Fock exchange in the quark-meson-coupling model influences the isovector channel and the density dependence of symmetry energy, comparing it with the Skyrme-Hartree-Fock model.

Contribution

It introduces a non-relativistic approximation of the quark-meson-coupling model highlighting the role of Fock exchange in symmetry energy behavior.

Findings

Fock exchange significantly affects finite nuclei and nuclear matter descriptions.

The nonlinear density dependence of the isovector channel arises from Fock exchange.

The symmetry energy's density dependence is altered by Fock exchange effects.

Abstract

The non-relativistic approximation of the quark-meson-coupling model has been discussed and compared with the Skyrme-Hartree-Fock model which includes spin exchanges. Calculations show that the spin-exchange interaction has important effect on the descriptions of finite nuclei and nuclear matter through the Fock exchange. Also in the quark-meson-coupling model, it is the Fock exchange that leads to a nonlinear density-dependent isovector channel and changes the density-dependent behavior of the symmetry energy.