A semiempirical evaluation of half-life of 146Sm isotope

A physical model that can quantitatively describe the spontaneous alpha-particle emission mechanism from atomic nuclei in the spherical nucleus approximation has been applied to the evaluation of the half-life of the [Formula: see text]Sm nuclide. The one-parameter, semi-empirical model used in this study has been developed in the frame of a quantum mechanical mechanism of alpha tunnelling through a potential barrier, taking into account centrifugal and overlapping effects. The calculation procedure yielded a value of [Formula: see text][Formula: see text]Myr for the half-life of the extinct [Formula: see text]Sm isotope. This value, even if in disagreement with the few old measurements performed on the artificially obtained [Formula: see text]Sm, is thought to represent the most reliable indication of the [Formula: see text]-decay rate for such challenging nuclide.