Entrance Channel Dependence of Production Cross Sections of Superheavy Nucleus ²⁶⁶Hs

Abstract：

For the ²⁶Mg+²⁴⁴Cm, ²⁷Al+²⁴³Am and ³²S+²³⁸U systems, the capture cross sections and the formation of the compound nucleus ²⁷⁰Hs are calculated and compared. In the entrance channel, the projectile is captured after overcoming the Coulomb barrier that has a distribution due to the deformation of the target nucleus. After contact, the system is assumed to be injected into an "asymmetric fission valley'' by the neutron induced neck formation. The dynamic process of the composite nucleus in the "asymmetric fission valley'' is treated in a two-parameter Smoluchowski equation in which neutron flow and diffusion in elongation coordinates are taken into account. The compound nucleus configuration is achieved only for those events where the system has diffused over the conditional saddle-point in the "asymmetric fission valley''. Our results show that the Coulomb barrier in the entrance channel and the height of the conditional saddle-point in the "asymmetric fission valley'' have obvious influence in the processes of the capture and compound nucleus formation.