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arXiv · 2201.02114

Anatomy of octupole correlations in $^{96}$Zr with a symmetry-restored multidimensionally-constrained covariant density functional theory

Yu-Ting Rong·Xian-Ye Wu·Bing-Nan Lu·Jiang-Ming Yao
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Abstract

A recent analysis based on the STAR measurement in relativistic heavy-ion collision experiments provides evidence of octupole correlation in the ground state of $^{96}$Zr, the description of which presents a challenge to nuclear structure models. In this work, we perform projection-after-variation calculations for $^{96}$Zr based on a multidimensionally-constrained relativistic Hartree-Bogoliubov model. Our results show that an octupole deformed shape is favored in energy after symmetry restoration, and this phenomenon cannot be reproduced in the pure mean-field calculations. These complex structures originate from the competition among various shell structures in this mass region. Our results suggest that the allowance of symmetry breaking at the mean-field level and the restoration of broken symmetries are essential elements for understanding the structure of $^{96}$Zr in density functional theories.

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Yu-Ting Rong, Xian-Ye Wu, Bing-Nan Lu, Jiang-Ming Yao. 2022-01-06. Anatomy of octupole correlations in $^{96}$Zr with a symmetry-restored multidimensionally-constrained covariant density functional theory. https://doi.org/10.1016/j.physletb.2023.137896

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