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arXiv · 2304.11780

Shape transition of Nd and Sm isotopes and neutrinoless double-beta decay nuclear matrix element of $^{150}$Nd

Yusuke Tsunoda·Noritaka Shimizu·Takaharu Otsuka
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Abstract

Neutron-rich Nd and Sm isotopes are known to exhibit shape phase transition as a function of neutron number. Among them, $^{150}$Nd and $^{150}$Sm are important not only because they are transitional nuclei, but also the parent and daughter nuclei of double-beta decay. We performed large-scale shell-model calculations of even-even Nd and Sm isotopes including the spherical-deformed shape transition. The quasi-particle vacua shell model enables us to perform shell-model calculations with sufficiently large model space with the $^{110}$Zr inert core. The shell-model result well reproduces the experimental excitation energies and quadrupole properties of the yrast and non-yrast states. The nuclear matrix element of neutrinoless double-beta decay of $^{150}$Nd is evaluated showing its modest enhancement by shape mixing.

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Yusuke Tsunoda, Noritaka Shimizu, Takaharu Otsuka. 2023-04-24. Shape transition of Nd and Sm isotopes and neutrinoless double-beta decay nuclear matrix element of $^{150}$Nd. https://doi.org/10.1103/physrevc.108.l021302

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