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arXiv · 2406.09803

Triaxial shape of the one-proton emitter $^{149}$Lu

Qi Lu·Kai-Yuan Zhang·Shi-Sheng Zhang
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Abstract

We revisit the proton emitter $^{149}$Lu utilizing the recently developed triaxial relativistic Hartree-Bogoliubov theory in continuum (TRHBc). By incorporating the microscopic nuclear structure properties from the TRHBc theory into the WKB approximation, we successfully reproduce the measured proton-emission half-life of $^{149}$Lu within experimental uncertainties. A triaxial ground state characterized by ($\beta=0.17,\gamma=31^\circ$) has been clarified for $^{149}$Lu. The inclusion of triaxiality significantly changes nuclear density distributions and potentials, which results in enhanced binding of both the nuclear system and the proton-emitting orbital. As a result, a slightly extended half-life for the proton emission of $^{149}$Lu is achieved after considering triaxial deformation degrees of freedom.

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Qi Lu, Kai-Yuan Zhang, Shi-Sheng Zhang. 2024-06-14. Triaxial shape of the one-proton emitter $^{149}$Lu. https://arxiv.org/abs/2406.09803

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