Isovector properties of the nuclear energy density functional from the quark-meson coupling model

TL;DR

This paper introduces a new nuclear energy density functional derived from the quark-meson coupling model, aiming to improve isovector property predictions with fewer phenomenological parameters, and demonstrates its effectiveness through nuclear structure calculations.

Contribution

The study develops a Skyrme-QMC functional based on the QMC model, reducing phenomenological assumptions and enhancing isovector property accuracy in nuclear calculations.

Findings

SQMC performs comparably to modern phenomenological functionals.

Isovector terms are crucial for neutron-rich nuclei binding energies.

Isovector dependence affects r-process nucleosynthesis predictions.

Abstract

Background: The Skyrme energy density functional is widely used in mean-field calculations of nuclear structure and dynamics. However, its reliance on phenomenology may compromise its isovector properties and its performance for exotic nuclear systems. Purpose: This work investigates the possibility of removing some phenomenology from the density functional by drawing on the high-energy degrees-of-freedom of the quark-meson coupling (QMC) model. The QMC model has microscopically derived isovector properties and far fewer adjustable parameters. Method: The parameters of the Skyrme interaction are fixed using the energy density functional of the QMC model, to give the Skyrme-QMC (SQMC) parameterisation. Results: Hartree-Fock-Bogoliubov calculations of the Sn, Pb and $N=126$ chains are reported, in which SQMC performs with an accuracy comparable to modern phenomenological functionals. Conclusions: The isovector terms of the energy density functional are significant for the binding energies of neutron-rich nuclei. The isovector dependence of the nuclear spin-orbit interaction must be taken into account for calculations of r-process nucleosynthesis abundances.