Fission path analysis in 48Ca-induced actinide reactions using the dynamical cluster-decay model

Abstract

Generally, the most probable fission path corresponds to the lowest energy in the fragmentation potential calculated within theoretical models. However, recent experimental mass yields measured in ⁴⁸Ca-induced actinide reactions show discrepancies compared to theoretical predictions based on the proximity potential (Prox77), particularly in the symmetric mass region. To investigate this discrepancy, the dynamical cluster-decay model is used, incorporating bulk and neutron-proton asymmetry coefficients, in the shape-dependent mass excess formula, recently updated to reproduce the ground-state mass excess data of AME2020 and/or FRDM(2012). Temperature dependence is used in both the deformation parameter and the surface energy coefficient of the proximity potential. Calculations are performed using various nuclear radius formulae. The most probable fission channel, corresponding to the minimum in the fragmentation potential, is found to match the experimental observations in both symmetric and asymmetric regions when using the radius formula of Bass along with the updated model inputs. The spherical and/or deformed shell closures associated with the most probable fission paths in the fission fragment mass distributions are analyzed. The most probable channels are associated with ¹³⁴Te in the symmetric region and lead isotopes (Pb) in the asymmetric region, except in the case of ²⁸⁰Ds^⁎. The dominant fission mode is asymmetric, which agrees with experimental findings.