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arXiv · 1003.2231

Octupole degree of freedom for the critical-point candidate nucleus $^{152}$Sm in a reflection-asymmetric relativistic mean-field approach

W. Zhang·Z. P. Li·S. Q. Zhang·J. Meng
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Abstract

The potential energy surfaces of even-even $^{146-156}$Sm are investigated in the constrained reflection-asymmetric relativistic mean-field approach with parameter set PK1. It is shown that the critical-point candidate nucleus $^{152}$Sm marks the shape/phase transition not only from U(5) to SU(3) symmetry, but also from the octupole-deformed ground state in $^{150}$Sm to the quadrupole-deformed ground state in $^{154}$Sm. By including the octupole degree of freedom, an energy gap near the Fermi surface for single-particle levels in $^{152}$Sm with $β_2 = 0.14 \sim 0.26$ is found, and the important role of the octupole deformation driving pair $ν2f_{7/2}$ and $ν1i_{13/2}$ is demonstrated.

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W. Zhang, Z. P. Li, S. Q. Zhang, J. Meng. 2010-03-11. Octupole degree of freedom for the critical-point candidate nucleus $^{152}$Sm in a reflection-asymmetric relativistic mean-field approach. https://doi.org/10.1103/physrevc.81.034302

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