https://doi.org/10.65770/CCMZ5800
ABSTRACT
Neutron skin thickness is an important structural property of neutron-rich superheavy nuclei because variations in the spatial extension of the neutron distribution can modify nuclear geometry, surface properties, interaction barriers, and radioactive-decay behaviour. This study presents a systematic comparative re-analysis of two previously developed approaches for cluster radioactivity and spontaneous fission: the conventional density-dependent cluster model within the Wentzel–Kramers–Brillouin (DDCM–WKB) framework and a unified neutron-skin-modified formulation that explicitly incorporates neutron skin thickness into nuclear geometry and barrier-dependent decay quantities. The objective is to determine quantitatively whether explicit neutron-skin treatment improves predictive performance relative to the conventional formulation. Cluster-radioactivity calculations exhibit pronounced nucleus-dependent sensitivity to barrier penetrability, Q-value, shell structure, daughter-nucleus configuration, and neutron skin effects, whereas spontaneous fission shows a more systematic variation with neutron skin thickness within the modified formulation. The conventional and neutron-skin-modified formulations previously reported root-mean-square (RMS) deviations of 1.822 and 1.437, respectively, for the available experimental spontaneous-fission half-life data. Direct comparison of these values in the present study corresponds to an RMS reduction of approximately 21.1%. Nucleus-resolved analysis further shows that the neutron-skin-modified formulation provides the closer prediction for six of the nine nuclei in the common experimental validation subset and substantially reduces systematic underprediction. However, the improvement is not universal across individual nuclei. Overall, the results indicate that explicit neutron-skin treatment improves the description of the available spontaneous-fission half-life data while neutron skin thickness remains one of several structural factors governing the competition between cluster radioactivity and spontaneous fission.
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