Fission barriers of heavy nuclei within a microscopic approach

The fission barriers of twenty-six isotopes of Thorium, Uranium, Plutonium, Californium, Fermium and Nobelium have been microscopically calculated up to and beyond the second saddle point within a constrained Hartree-Fock plus pairing approach. The Skyrme density-dependent effective force in its SkM* parametrization-rather well suited to the description of fission barriers-has been used in the particle-hole channel, whereas the usual HF plus BCS formalism with either a seniority force or a delta force has been implemented to treat pairing correlations. The energy correction due to the rotational zero-point motion has been approximately taken into account and the effects of triaxial and reflection asymmetric deformations have been investigated. When known, the experimental fission barrier heights are reproduced within about 1-2 MeV.