Cluster decay dynamics of Actinides yielding non-Pb-daughter

TL;DR

This study investigates the decay of actinides into non-Pb daughters using a novel preformation formula within the relativistic mean-field approach, providing new insights into cluster decay energies and shell effects.

Contribution

It introduces a new preformation formula for cluster decay, quantifies preformation energy, and compares phenomenological and microscopic potentials within the PCM framework.

Findings

Predictions agree well with experimental half-lives.

Shell effects influence cluster emission kinematics.

Recoil energy systematics can aid superheavy element synthesis.

Abstract

The cluster dynamics of radioactive nuclei decaying to neighbouring daughter nuclei of the double magic $^{132}$Sn and $^{208}$Pb is investigated using the relativistic mean-field (RMF) approach with NL3$^*$ parameter set within the preformed cluster-decay model (PCM). The novel feature of the present study is the application of the newly derived preformation formula, laying the groundwork for accessing the break-up of the Q-value: preformation energy, cluster emission energy and the recoil energy of the daughters formed. The energy associated with cluster preformation is theoretically quantified for the first time. This treatment underscores the shell effect, pairing correlation as well as the blocking of particular orbitals by unpaired nucleons. To ascertain the applicability of the new formula, the PCM based calculations are carried out with nuclear potential obtained using the phenomenological M3Y and microscopic RMF-based R3Y nucleon-nucleon (NN) potentials along with corresponding densities. We found a marginal variation that can be attributed to the difference in their barrier properties, however, the predictions for the case of both M3Y and R3Y potentials are found to agree well with the experimental half-lives. Although none of the considered reaction systems yields a double magic daughter nucleus, we found that the kinematics of their cluster emissions is governed by their proximity to the shell closure. The deduced systematic of the recoil energy in cluster decays can provide valuable insight for the synthesis of elements in superheavy mass region in the future.