Post-Neutron Mass Yield Distribution in the Spontaneous Fission of ~(252)Cf

摘要

Cumulative and independent yields of various fission products within mass ranges of 86 to 119 and 127 to 162 were measured in the spontaneous fission of ~(252)Cf by using an off-line gamma-ray spectrometric technique. From the cumulative yields of the fission products, their mass chain yields were obtained by using the charge distribution correction. Mass yield distribution parameters such as full-width at tenth-maximum of light and heavy mass wings, average light mass and heavy mass , and total average neutron multiplicity < ν>_(expt) were obtained. Fission yield data in the ~(252)Cf(SF) reaction were compared with similar data in neutron-induced fission and spontaneous fission of other actinides to examine the role of excitation energy and nuclear structure effect. The role of standard Ⅰ and standard Ⅱ asymmetric modes of fission is also discussed.