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arXiv · 2503.01398

Effective proton-neutron interaction in mirror nuclei

Y. M. Xing·Y. F. Luo·K. H. Li·Y. H. Zhang·J. G. Li·M. Wang·Yu. A. Litvinov·K. Blaum·X. L. Yan·T. Liao·M. Zhang·X. Zhou
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Abstract

Effective proton-neutron interactions, $V_{pn}$, in mirror nuclei are systematically analyzed using the ground-state atomic masses. A mirror symmetry of $V_{pn}$ is found for bound nuclei with a standard deviation of $\sigma=32$ keV. However, this mirror symmetry is apparently broken for some mirror-nuclei pairs when a proton-unbound nucleus is involved in extracting the $V_{pn}$ values. Such a mirror-symmetry breaking is attributed to the Thomas-Ehrman shift of the proton-unbound nucleus and investigated by using the Gamow shell model. It is concluded that the Thomas-Ehrman shift originates mainly from reduced Coulomb energies in the proton-unbound nuclei due to the extended radial density distribution of valence protons.

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Y. M. Xing, Y. F. Luo, K. H. Li, Y. H. Zhang, J. G. Li, M. Wang, Yu. A. Litvinov, K. Blaum, X. L. Yan, T. Liao, M. Zhang, X. Zhou. 2025-03-03. Effective proton-neutron interaction in mirror nuclei. https://arxiv.org/abs/2503.01398

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