Multidimensional model of cluster radioactivity

The cluster decays Th-228 -> Pb-208 + O-20, U-232 -> Pb-208 + Ne-24, Pu-236 -> Pb-208 + Mg-28, and Cm-242 -> Pb-208 + Si-34 are considered in the framework of the multidimensional cluster-preformation model. The macroscopic potential-energy surface related to the interaction between the cluster and the residue nucleus is evaluated in the framework of the nonlocal h(4) extended Thomas-Fermi approach with Skyrme and Coulomb forces. The shell correction to the macroscopic potential energy is also taken into account. The dynamical surface deformations of both the cluster and the residue nucleus are taken into consideration at the barrier penetration path. The heights of saddle points related to deformed nuclear shapes are lower than the barrier height between the spherical cluster and residue nuclei; therefore the dynamical deformations of nuclei increase the barrier penetrability and reduce the half-life of cluster decay. The shell-correction contribution into the potential energy between cluster and residue nucleus is important for both the potential landscape and the half-life evaluation. The experimental values of cluster-decay half-lives are well reproduced in the model.