Accurate spontaneous fission half-lives from a microscopic large-scale nuclear structure model

Adrián Sánchez-Fernández; Silvia Bara; Wouter Ryssens; Stéphane Goriely

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arXiv · 2508.16240

Accurate spontaneous fission half-lives from a microscopic large-scale nuclear structure model

Adrián Sánchez-Fernández·Silvia Bara·Wouter Ryssens·Stéphane Goriely

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Abstract

We demonstrate the ability of the BSkG3 model to predict large-scale fission properties. In particular, we focus on the description of spontaneous fission half-lives, which are crucial for modeling the r-process. To assess the model accuracy, we compare predicted and experimental values for all nuclei with available data. The combination of BSkG3 predictive power for ground state and fission properties, the inclusion of triaxial and octupole degrees of freedom, the use of microscopic collective inertias, and the minimization of the action make our approach sophisticated yet practical when it comes to large-scale astrophysical applications.

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Adrián Sánchez-Fernández, Silvia Bara, Wouter Ryssens, Stéphane Goriely. 2025-08-22. Accurate spontaneous fission half-lives from a microscopic large-scale nuclear structure model. https://arxiv.org/abs/2508.16240

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