Generalization of α-Decay Cluster-Model to Nuclei Near Spherical and Deformed Shell Closures

摘要

＜正＞ The cluster model of α-decay is extended to the regions around doubly magic spherical nucleus 208Pband around deformed shell closure 270Hs,respectively.The effects of spherical shell closures （N=126 and Z=82） onα-decay are investigated by introducing an N-dependent α-preformation factor and a Z-dependent one inspired by amicroscopic model.Good agreement between the theoretical α-decay hag-fives and the measured ones is obtained forthe spherical nuclei near the doubly magic nucleus 208Pb,where the nuclear shell effect is included in the expression ofα-preformation factor.The cluster model is also generalized for the decay of deformed nuclei.The branching ratios ofα-decays from the ground state of a parent nucleus to the ground state （0+） of its deformed daughter nucleus and to thefirst excited state （2+） are calculated in the framework of the cluster model.The results indicate that a measurement ofa spectroscopy is a feasible method to extract the information of nuclear deformation of superheavy nuclei around thedeformed nucleus 270Hs.