Nuclear surface diffuseness in cluster decay

Abstract

Yukawa-plus-exponential potential, a generalisation of modified liquid drop model, incorporates the finite range of nuclear force and diffuse nuclear surface. The range of Yukawa folding function, a, accounts for both surface diffuseness and saturation condition. The present study deals with the influence of a, in experimentally identified cluster decay of heavy nuclei. Further, its dependence on neutron excess of the parent nucleus, has been studied. For the experimentally identified cluster emitters, systematic calculations for values of a between 0.54 fm and 0.8 fm have been carried out. The results suggest that as a increases, the nuclear interaction potential widens and deepens, which subsequently influences the total potential. The study shows the dependence of surface diffuseness on neutron excess of isotopes of a parent nucleus. A correlation between a, corresponding to the best-matching half-lives with experimental ones, and the neutron excess of the corresponding parent nuclei has been carried out with an appropriate fitting function. Based on the good agreement between the calculated and experimental half-lives and the branching ratio for cluster emission relative to alpha, the analysis has been extended to alpha and cluster emission of heavy and superheavy nuclei in the range \(99\le Z \le 116\) with \(252 \le A \le 293\). Half-lives of alpha decay of the superheavy nuclei match reasonably well with the experimental values. Predicted half-lives of the clusters, \(^{46}\)Ar and \(^{48}\)Ca from \(^{253}\)Es and \(^{252}\)Fm respectively, compare well with other predictions.