Recent Investigations of Superheavy Elements

Abstract

We investigate [1] the possibilities of the formation of superheavy nuclei in cold fusion reactions [2] with the emission of only one neutron [3, 4]. We refine [1] our original quantal model [5]. The refinement consists in using a smooth effective fusion barrier with the height and the curvature modeled phenomenologically. Moreover, the survival probability of the compound nucleus is calculated by using a modified statistical model formula. The latter takes implicitly into account the influence of shell effects on the level density through different temperatures for the equilibrium and the saddle-point configurations. The optimal bombarding energy corresponding to the maximum of the excitation function is calculated as the sum of thresholds for neutron emission and fission following neutron emission. We reproduce measured formation cross sections of elements Z=102–112 [3, 4, 6, 7]. All the details of the calculation are given in Ref.[1].