Predictions of alpha decay half lives of heavy and superheavy elements

Abstract

Theoretical estimates for the lifetimes of several isotopes of heavy elements with Z = 102 – 120 are presented by calculating the quantum mechanical tunneling probability in a WKB framework and using microscopic nucleus–nucleus potential obtained by folding the densities of interacting nuclei with the DDM3Y effective nuclear interaction. The α-decay half lives calculated in this formalism using the experimental Q-values are in good agreement over a wide range of experimental data. Half lives are also calculated using Q-values extracted from two mass formulae. The Viola–Seaborg–Sobiczewski (VSS) estimates of α-decay half lives with the same Q-values are presented for comparison. The half life calculations are found to be quite sensitive to the choice of Q-values. Comparison with the experimental data delineates the inadequacies of older mass predictions in the domain of heavy and superheavy elements as compared to the newer one by Muntian–Hofmann–Patyk–Sobiczewski, and highlights necessity of a more accurate mass formula which can predict Q-values with even higher precision.