POTENTIAL-ENERGY SURFACES OF SUPERHEAVY NUCLEI

We investigate the structure of the potential energy surfaces of the s uperheavy nuclei Fm-258(158)100, (264)(156)Hs(108), (278)(166)112, (29 8)(184)114, and (292)(172)120 within the framework of self-consistent nuclear models, i.e., the Skyrme-Hartree-Fock approach and the relativ istic mean-field model. We compare results obtained with one represent ative parametrization of each model which is successful in describing superheavy nuclei. We find systematic changes as compared to the poten tial energy surfaces of heavy nuclei in the uranium region: there is n o sufficiently stable fission isomer any more, the importance of triax ial configurations to lower the first barrier fades away, and asymmetr ic fission paths compete down to rather small deformation. Comparing t he two models, it turns out that the relativistic mean-field model giv es generally smaller fission barriers. [S0556-2813(98)05510-1].