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arXiv · 2510.16313

Symmetry restoration in the axially deformed proton-neutron quasiparticle random phase approximation for nuclear beta decay: The effect of angular-momentum projection

R. N. Chen·Y. N. Zhang·J. M. Yao·J. Engel
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Abstract

We examine the effects of symmetry restoration on nuclear beta decay within the axially deformed proton-neutron quasiparticle random phase approximation (QRPA). We employ the proton-neutron finite-amplitude method (pnFAM) to compute transition amplitudes, and perform angular-momentum projection both after variation and after the QRPA to restore rotational symmetry. Exact projection reduces the calculated beta decay half-lives from those that use the needle approximation by up to 60%, and even more when taking the effects of projection on the ground-state energy into account.

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R. N. Chen, Y. N. Zhang, J. M. Yao, J. Engel. 2025-10-18. Symmetry restoration in the axially deformed proton-neutron quasiparticle random phase approximation for nuclear beta decay: The effect of angular-momentum projection. https://doi.org/10.1103/lk7x-bqdf

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