On the shape of prompt neutron spectrum from 252Cf spontaneous fission

The spectrum of prompt neutrons from the 252Cf spontaneous fission has been measured by the time-of-flight method within the wide energy range of 0.01-10 MeV using the detectors on the basis of 235U. The results of studies are analysed and weight average of spectrum within the energy range from 0.01 to 12 MeV are calculated. On the basis of the data obtained the spectrum excess over the Maxwell distribution is shown to be equal to approximately 20% within the energy range of 0.05-0.15 MeV and to 5-7% within the energy range of 0.15-0.4 MeV