Shell Effect of Superheavy Nuclei in Self-consistent Mean-Field Models

We analyze in detail the numerical results of superheavy nucleiin deformed relativistic mean-field model and deformedSkyrme-Hartree-Fock model. The common points and differences ofboth models are systematically compared and discussed. Theirconsequences on the stability of superheavy nuclei are exploredand explained. The theoretical results are compared with new dataof superheavy nuclei from GSI and from Dubna and reasonableagreement is reached. Nuclear shell effect in superheavy regionis analyzed and discussed.The spherical shell effect disappears in some cases due to the appearance of deformation or superdeformation in the ground states of nuclei, where valence nucleons occupy significantly the intruder levels of nuclei. It is shown for the first time that the significant occupation of valence nucleons on the intruder states plays an important role for the ground state properties of superheavy nuclei. Nuclei are stable in the deformed or superdeformed configurations. We further point out that one cannot obtain the octupole deformation of even-even nuclei in the present relativistic mean-field model with the σ, ω and ρmesons because there is no parity-violating interaction and theconservation of parity of even-even nuclei is a basic assumptionof the present relativistic mean-field model.