Isotopic yields for the cold fission of 252 Cf

The isotopic yields for the spontaneous cold fission of 252 Cf are predicted by using a double folding potential and the M3Y nucleon-nucleon force with central, isospin and single nuclear exchange terms. The spin-spin and spin-isospin components are disregarded since their contributions tend to be very small. We evaluate the nuclear plus Coulomb interaction between two coaxial deformed fragments by making a general multipole expansion of the potential. The penetrabilities through the barrier between the two final nuclei are obtained within the one-dimensional WKB approximation. Realistic fragment ground-state deformations are used for the calculations. The results are in good agreement with zero neutron channel yields extracted from γ-γ-γ coincidence studies in the spontaneous fission of 252 Cf recorded with the early version of the Gammasphere detector. The double fine structure in such cold fragmentation has been experimentally observed for the first time