Ternary Fission of Cf-249(n,f) and Cf-250(SF)

During the last years, several Cm and Cf isotopes have been studied by our research group in the frame of a systematic investigation of gas emission characteristics in ternary fission. Here we report on new results on the energy distribution and the emission probability of H-3, He-4 and He-6 particles emitted in the spontaneous ternary fission of Cf-250 (E-exc, = 0 MeV) and in the neutron induced ternary fission of Cf-249 (E-exc = 6.625 MeV). Both measurements were performed using suited and well-calibrated Delta E-E telescope detectors, at the IRMM (Geel, Belgium) for the spontaneous fission and at the very intense neutron beam PF1b at the Institute Laue-Langevin (Grenoble, France) for the neutron induced fission measurement. In this way, the existing database can be enlarged with new results for Z=98 isotopes, which is important for the systematic investigation. Moreover, the investigation of the 'isotope couple' Cf-249(n,f) - Cf-250(SF), together with corresponding data for other isotopes, will yield valuable information on the influence of the excitation energy on the particle emission probabilities.