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arXiv · 2603.25359

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

T. Popa·N. Sandulescu·D. Gambacurta
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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.

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T. Popa, N. Sandulescu, D. Gambacurta. 2026-03-26. Proton-Neutron Pairing in N=Z Nuclei within the Quark-Meson-Coupling Energy Density Functional. https://arxiv.org/abs/2603.25359

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