Proton-Neutron Pairing in N=Z Nuclei within the Quark-Meson-Coupling Energy Density Functional

TL;DR

This study explores how proton-neutron pairing correlations influence the ground-state properties of N=Z nuclei using the quark-meson coupling energy density functional and quartet condensation model, showing improved agreement with experimental data.

Contribution

It introduces a combined QMC and QCM approach to account for proton-neutron pairing in N=Z nuclei, enhancing the understanding of their ground-state energies.

Findings

Proton-neutron pairing significantly affects binding energies.

The combined QMC+QCM model improves agreement with experimental data.

Pairing correlations are crucial for accurate nuclear structure predictions.

Abstract

We investigate the impact of isovector and isoscalar proton-neutron pairing correlations on the ground-state properties of even-even N=Z nuclei with mass numbers between A=16 and A=120. Nuclear mean fields are generated using the quark-meson coupling (QMC) energy density functional, while pairing correlations are treated within the quartet condensation model (QCM). Ground-state energies are obtained from axially deformed, self-consistent QMC+QCM calculations employing a zero-range pairing interaction with a density-dependent term derived consistently within the QMC framework. We show that proton-neutron pairing provides a significant contribution to the binding energies of N=Z nuclei, leading to improved agreement with experimental data.