Semi-classical calculations of the α decay half-lives for even-even nuclei

The half-lives of the alpha decay for even-even nuclei having Z = 62-118 (164 nuclei) have been calculated by using the Wentzel-Kramers-Brillouin (WKB) method together Bohr-Sommerfeld (BS) quantization condition for cosh potential in two-different forms with and without the isospin effects for six different parameter sets. By comparing the obtained results with the experimental values, the rms deviations have been computed. It is obtained that when the cosh potential is used in 2 different type forms, the rms values are also changed and the better one for obtaining the half-lives is cosh-2 form. Even if the isospin-dependent potential does not have so much effect on rms values in this sort of WKB with BS calculations with cosh potential forms, considering the isospin effect together the isospin-dependent nuclear diffuseness parameter have a strong influence on the rms values. New hindrance factor formula based on liquid drop model was used in order to show the influence of hindrance factor on the alpha decay half-lives. It is pointed out that this new function of the hindrance factor does not depend on the magic numbers, it contains fewer free parameters and using of this improves the calculations positively. New estimates by using present model have also been made for even-even nuclei having with Z = 118-120 which do not have the measured alpha decay half-lives yet and they have been compared the results of the ImSahu model. The present results would provide useful information and knowledge for the explanation of half-lives of alpha decay of nuclei and future possible experimental studies.