Exoticαdecays around theN=126magic shell

Abstract

We investigate the $\alpha$-decay half-lives of the exotic $N=125,126,127$ isotones by the generalized density-dependent cluster model (GDDCM) in combination with the microscopic two-level model. The decay widths are calculated using the overlap integral of the quasibound state wave function, the scattering state wave function, and the difference of potentials, instead of using the simple semiclassical WKB method along with the Bohr-Sommerfeld quantization condition. The $\alpha$-preformation factors are evaluated by the $Z$-dependent formula based on the two-level model, where the closed-shell effect is included. The calculated half-lives of $\alpha$ transitions to both ground states and excited states are found to be in good agreement with the experimental data.