The calculated $Q$ values and half widths of α-decay of superheavy elements using both the S-matrix and the WKB methods are analyzed. The calculations are carried out using the microscopically derived α-daughter potentials for the parents appearing in the α-decay chain of super heavy element ($A=277,Z=112$). Both the S-matrix and the WKB methods though yield comparable results for smaller, in fact negative log ${\tau }_{1/2}$ values, the former is superior. However, for the case of positive log ${\tau }_{1/2}$ it is found that the S-matrix method though exact, runs into some numerical difficulties.

• Received 25 April 2006

DOI:https://doi.org/10.1103/PhysRevC.74.057601