Cluster approach to spontaneous fission of even-even isotopes of U, Pu, Cm, Cf, Fm, No, Rf, Sg, and Hs

Abstract

For even isotopes of nuclei U, Pu, Cm, Cf, Fm, No, Rf, Sg, and Hs, spontaneous fission and $\ensuremath{\alpha}$-decay half-lives are calculated within the dinuclear system model and compared with existing experimental data. Cluster radioactivity half-lives are also described for even U, Pu, and Cm isotopes. All these processes are considered for the evolution of a nucleus in the charge (mass) asymmetry coordinate and in the relative distance between the centers of clusters formed. The important roles of the driving potential and mass parameter in the charge asymmetry coordinate are shown for spontaneous fission. The global isotopic trends of spontaneous fission and $\ensuremath{\alpha}$-decay half-lives are studied. Drastic changes in the functional dependence of spontaneous fission half-life on the neutron number and in the absolute values of half-lives in the U--No and Rf--Hs nuclear groups are explained.