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arXiv · 2309.07903

Shell-model study for allowed and forbidden $\beta^-$ decay properties in the mass region "south" of $^{208}$Pb

Shweta Sharma·Praveen C. Srivastava·Anil Kumar·Toshio Suzuki·Cenxi Yuan·Noritaka Shimizu
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Abstract

The large-scale shell-model calculations have been performed for the neutron-rich nuclei in the south region of $^{208}$Pb in the nuclear chart. The $\beta$-decay properties, such as the $\log ft$, average shape factor values, half-lives, and partial decay rates are calculated for these neutron-rich nuclei using recent effective interaction for the $^{208}$Pb region. These calculations have been performed without truncation in a particular model space for nuclei $N\leq 126$; additionally, particle-hole excitations are included in the case of core-breaking nuclei ($Z\leq 82, N>126$). An extensive comparison with the experimental data has been made, and spin parities of several states have been proposed.

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Shweta Sharma, Praveen C. Srivastava, Anil Kumar, Toshio Suzuki, Cenxi Yuan, Noritaka Shimizu. 2023-09-14. Shell-model study for allowed and forbidden $\beta^-$ decay properties in the mass region "south" of $^{208}$Pb. https://doi.org/10.1103/physrevc.110.024320

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