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arXiv · 2303.04990

Deformed ground state of $^{32}$Mg and breaking of pseudo-spin symmetry

Yong Peng·Jing Geng·Yi Fei Niu·Wen Hui Long
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Abstract

Deformed ground state of $^{32}$Mg is investigated using the axially deformed relativistic Hartree-Fock-Bogoliubov (D-RHFB) model with the effective Lagrangian PKA1, which provides coincident description with the experimental measurements. It is illustrated that obvious breaking of the pseudo-spin symmetry (PSS) given by PKA1, being consistent with the experimental observation in nearby isotone $^{40}$Ca, is crucial for describing correctly the deformed ground state by producing unique shape evolution of neutron orbit $1/2_4^+$ in $^{32}$Mg. The PSS breaking is essentially determined by characteristic in-medium balance between nuclear attractions and repulsions that is manifested as unparalleled density dependent behaviors for coupling strengths $g_\sigma$ and $g_\omega$ in dominant $\sigma$-scalar and $\omega$-vector channels.

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Yong Peng, Jing Geng, Yi Fei Niu, Wen Hui Long. 2023-03-09. Deformed ground state of $^{32}$Mg and breaking of pseudo-spin symmetry. https://arxiv.org/abs/2303.04990

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