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arXiv · 2511.05918

Search for shape-isomers in the Pt-Hg-Pb region

J. Bartel·H. Molique·B. Nerlo-Pomorska·M. Warda·K. Pomorski
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Abstract

Potential energy surfaces of nine even-even isotopes of Pt, Hg, and Pb around $^{186}$Pt are evaluated within a macroscopic-microscopic model based on the Lublin-Strasbourg-Drop macroscopic energy and the microscopic energy obtained using the Yukawa-folded mean-field potential to establish the Strutinski shell corrections and the pairing correlation energy through the BCS approach with a monopole pairing force. The rapidly converging Fourier-over-Spheroid shape parametrization is used to describe nuclear deformations. The stability of the identified shape isomeric states with respect to non-axial and higher-order deformations is investigated. It is also found that in the description of non-axial deformations special attention needs to be devoted to the orientation of the triaxial shape. For the example of the $^{186}$Hg nucleus, where three prolate shape-isomeric states are found, it is shown that the potential energy surface obtained in our model is close to the one obtained in the Hartree-Fock-Bogoliubov theory with the Gogny energy-density functional.

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J. Bartel, H. Molique, B. Nerlo-Pomorska, M. Warda, K. Pomorski. 2025-11-08. Search for shape-isomers in the Pt-Hg-Pb region. https://doi.org/10.1103/gk8b-jl6y

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