α-decay half-lives in medium mass nuclei

Systematical calculations on the alpha-decay half-lives of even-even medium mass nuclei with 82 < N <= 126 are carried out within the density-dependent cluster model using a two-potential approach. The decay width is achieved in terms of the bound state wavefunction, the scattering wavefunction and the outer potential, where the effective alpha-nucleus potential is obtained from the double-folded integral of the realistic nucleon-nucleon interaction with the mass distributions of a particle and daughter nucleus. Instead of the Wentzel-Kramers-Brillouin (WKB) barrier penetration probability, the numerical solution of the Schrodinger equation for the bound state is presented. In addition, the shell effect on the alpha-preformation factor has been taken into account for even-even N = 126 isotones. The calculated alpha-decay half-lives are found to agree with experimental data with a mean factor of less than 2.