Theoretical Investigation of α-decay Chains of Fm-isotopes

Abstract

Background: The theoretical and experimental investigations of decay properties of heavy and superheavy nuclei are crucial to explore the nuclear structure and reaction dynamics. Purpose: The aim of this study is to probe the α-decay properties of ²⁴³Fm and ²⁴⁵Fm isotopic chains using relativistic mean-field (RMF) approach within the framework of preformed cluster-decay model (PCM). Methods: The RMF densities are folded with the relativistic R3Y NN potential to deduce the nuclear interaction potential between the α particle and daughter nucleus. The penetration probability is calculated within the WKB approximation. Results: The α-decay half-lives of even-odd ²⁴³Fm and ²⁴⁵Fm isotopes and their daughter nuclei are obtained from the preformed cluster-decay model. These theoretically calculated half-lives are found to be in good agreement with the recent experimental measurements. Conclusions: The novel result here is the applicability of the scaling factor within the PCM as a signature for shell/sub-shell closures in α-decay studies. As such, we have also demonstrated that N=137, 139 and Z=94 corresponding to ^231,233Pu could be shell/sub-shell closures. The least T_1/2 is found at ^243,245Fm which indicate their individual stability and α-decay as their most probable decay mode.