EFFECT OF NON-AXIAL DEFORMATIONS OF HIGHER MULTIPOLARITY ON THE FISSION-BARRIER HEIGHT OF HEAVIEST NUCLEI

The static fission-barrier height B-f(st) of heaviest nuclei is studied in a multidimensional deformation space. The main attention is given to the effect of the hexadecapole non-axial shapes on B-f(st). The analysis is performed within a macroscopic-microscopic approach. A 10-dimensional deformation space is used. A large number of about 300 even-even heavy and superheavy nuclei with proton number 98 <= Z <= 126 and neutron number 134 <= N <= 192 are considered. It is found that the inclusion of the non-axial hexadecapole shapes lowers the barrier by up to about 1.5 MeV.