Cross sections for fission of 244Cm and 246Cm by neutrons in the near-threshold energy region

The time-of-flight method with use of a nuclear explosion as a pulsed source of neutrons has been used to measure the energy dependence of the fission cross sections of 244Cm and 246Cm in the energy range 0.3< or =E/sub n/< or =4.5 MeV with a resolution 4.6 nsec/m. The effective parameters of the fission thresholds of these nuclei are determined. Some features of the fission cross sections near threshold are discussed