Alpha clustering preformation probability in even-even and odd-A270−317(116 and 117) using cluster formation model and the mass formulae : KTUY05 and WS4

The calculations were carried out using an energy-dependent formula, where the superheavy-nuclei mass defect was evaluated by using both the KTUY05 and WS4 nuclear mass formulae. This formula reproduced successfully the value of 212Po calculated from a combined microscopic shell and cluster model and described satisfactorily the alpha decay of heavy nuclei. The values of the preformation probability and the cluster formation energy, and their dependence on the neutron number, confirmed the shell and subshell closures and the similarities of alpha clustering between heavy and superheavy nuclei. The calculations carried out with the WS4 mass formula showed larger alpha-clustering effects than the KTUY05. •Alpha clustering is represented with a factor called preformation factor, preformation probability.•Alpha formation energy is determined from a formula derived from the nucleon-nucleon interaction (pairing energy) that is calculated from the binding energy.•Superheavy mass formulae: KTUY05 and WS4 were evaluated.•The use of WS4 led to PF values with very slight difference from the KTUY05 in the present work.•The cluster formation energy reveals magic and submagic at N = 162, 178, 184, 190 (in only TUY05) and 194 (in only WS4).