Theoretical studies on the fine structure of α decay for even-odd and even-even isotopes of Cm, Cf, Fm and No nuclei

Using the cubic plus Yukawa plus exponential model (CYEM), half-lives of α decay from the ground state of the parent nuclei to the ground state of the daughter nuclei and from the ground state to an excited state of the daughter nuclei have been systematically investigated for even-odd and even-even isotopes of Cm, Cf, Fm and No nuclei by incorporating centrifugal potential term, rotational energy term, deformation effects (β₂ and β₄) of the parent and daughter nuclei and spin-parity effects.We have done our calculations by considering the Coulomb, centrifugal and Yukawa plus exponential potentials as an interacting barrier for separated fragments and the cubic potential for the overlapping region. The calculated half-lives are compared with the available data. Our results are found to be in good agreement with each other. The effect of the centrifugal potential on half-life was evaluated. The branching ratio, hindrance factor and standard deviation of half-lives from the ground state of the parent nuclei to the ground state of the daughter nuclei have been calculated. (author)