Adiabatic fusion barriers from self-consistent calculations

Adiabatic fusion barriers are studied within the static Hartree-Fock method with the effective Skyrme interactions SkM* and SLy6. The problem of kinetic energy of the relative motion becoming spurious for separate fragments, relevant for both fusion and fission barriers, is discussed in some detail. Also discussed are the specific assumptions necessary to compensate for the nonuniqueness of the static method. Barriers obtained with two forces agree to within 2 MeV and seem nearly decoupled from errors in binding energies, specific to each force. For a number of reactions, comparisons are made with experimental estimates of barriers and barriers calculated with the frozen densities. The adiabatic barriers are generally lower than the experimental estimates. The offset amounts to less than 3 MeV in lighter systems and varies between 0 and ∼10 MeV in heavy ones. Compared to the data, the frozen-density barriers in heavy systems do not seem more realistic than ours, perhaps, except for tip collisions with deformed heavy targets. We also calculate HF energy surfaces for three heavy systems, looking for a relation between adiabatic potential and the fusion hindrance at large ZTZP. One can see a link between quasifission and the force opposing fusion, acting inside the Coulomb barrier. One surface illustrates the identity of the adiabatic fusion barrier with the fission saddle of a compound nucleus