Study of the Mo-Ba partition in 252Cf spontaneous fission

Measurements of fission fragment yields and neutron multiplicities have been carried out for the Mo-Ba fragment pairs in the spontaneous fission of ²⁵²Cf, using the γ-ray spectroscopy technique to analyze γ-γ-γ coincidence data. Prompt γ -ray multiplicities were also measured as a function of the number of neutrons emitted in the fission process leading to the Mo-Ba partition. We do not observe the enhancement in the yields of events with high neutron emission multiplicity (ν_n > 7) that has been associated to a second fission mode leading to the production of hyperdeformed Ba fragments, as reported in some earlier studies. The average γ-ray multiplicity is found to be rather weakly dependent on the number of neutrons emitted in the fission process. Received: 21 July 1999 / Revised version: 19 November 1999