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arXiv · 1907.00597

Pseudo-spin symmetry restoration and the in-medium balance between nuclear attractive and repulsive interactions

Jing Geng·Jia Jie Li·Wen Hui Long·Yi Fei Niu·Shi Yao Chang
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Abstract

The mechanism that restores the pseudo-spin symmetry (PSS) are investigated under the relativistic Hartree-Fock (RHF) approach, by focusing on the in-medium balance between nuclear attractive and repulsive interactions. It is illustrated that the modelings of both the equilibrium of nuclear dynamics and the in-medium effects can be essentially changed by the $ρ$-tensor coupling that play the role almost fully via the Fock terms, from which the model discrepancy on the PSS restoration is verified. Specifically, the largely different density-dependent behaviors of the isoscalar coupling strengths $g_σ$ and $g_ω$, deduced from the parametrization of the RHF Lagrangian PKA1, play an essential role in restoring the PSS of the high-$l'$ pseudo-spin doublets around the Fermi levels. Qualitatively, a guidance is provided for the modelings of both the equilibrium of nuclear dynamics and the in-medium effects via the PSS restoration.

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Jing Geng, Jia Jie Li, Wen Hui Long, Yi Fei Niu, Shi Yao Chang. 2019-07-01. Pseudo-spin symmetry restoration and the in-medium balance between nuclear attractive and repulsive interactions. https://doi.org/10.1103/physrevc.100.051301

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