Structure properties of Th 226 and Fm 256 , 258 , 260 fission fragments: Mean-field analysis with the Gogny force

The constrained Hartree-Fock-Bogoliubov method is used with the Gogny interaction DlS to calculate potential energy surfaces of fissioning nuclei 226 Th and 256,258,260 Fm up to very large deformations. The constraints employed are the mass quadrupole and octupole moments. In this subspace of collective coordinates, many scission configurations are identified ranging from symmetric to highly asymmetric fragmentations. Corresponding fragment properties at scission are derived yielding fragment deformations, deformation energies, energy partitioning, neutron binding energies at scission, neutron multiplicities, charge polarization, and total fragment kinetic energies.