Effects of differences between neutron and proton density distributions onα-decay half-lives

Abstract

The neutron skin of heavy nuclei is one of the hot topics in contemporary nuclear physics. In this article, effects of differences between neutron and proton density distributions on $\ensuremath{\alpha}$ decay are investigated. $\ensuremath{\alpha}$-decay calculations are performed within the generalized density-dependent cluster model, where the $\ensuremath{\alpha}$-core potential is determined in the double-folding model using the neutron and proton density distributions of daughter nuclei. The proton and neutron density distributions, assumed to be of two-parameter Fermi form, are constrained by the experimental nuclear charge radii as well as the neutron skin thickness of heavy nuclei. The resulting distribution of daughter nuclei results in an improved $\ensuremath{\alpha}$-core potential which is important for $\ensuremath{\alpha}$-decay calculations. It is found that the neutron skin thickness plays an important role in reducing the calculated $\ensuremath{\alpha}$-decay half-lives, implying a smaller $\ensuremath{\alpha}$ preformation factor. The calculations with neutron skin thickness show good agreement with the available experimental data for even-even nuclei including the known heaviest nuclei.