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arXiv · 2511.02999

Large-Scale Calculations of $\beta$-Decay Rates and Implications for $r$-Process Nucleosynthesis

A. Ravlić·Y. Saito·W. Nazarewicz
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Abstract

Nuclear $\beta$ decay is a key element of the astrophysical rapid neutron capture process ($r$-process). In this paper, we present state-of-the-art global $\beta$-decay calculations based on the quantified relativistic nuclear energy density functional theory and the deformed proton-neutron quasiparticle random-phase approximation. Our analysis considers contributions from allowed and first-forbidden transitions. We used two point-coupling functionals with carefully calibrated time-odd terms and isoscalar pairing strength. The new calculations display consistent results for both employed functionals, especially near the neutron drip line, suggesting slower $\beta$ decays past the $N=126$ neutron shell closure than in commonly used $\beta$-decay models. The new rates, along with the existing rates based on the latest non-relativistic calculations, are found to slow down the synthesis of heavy elements in the $r$-process and significantly reduce the contribution of neutron-induced fission.

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A. Ravlić, Y. Saito, W. Nazarewicz. 2025-11-04. Large-Scale Calculations of $\beta$-Decay Rates and Implications for $r$-Process Nucleosynthesis. https://arxiv.org/abs/2511.02999

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