Prompt neutron spectrum and average neutron multiplicity in spontaneous fission of252Cf

Abstract

A simple analytical expression is introduced for the average neutron multiplicity depending on the fission fragment mass using directly the prompt neutron energy spectrum in the framework of statistical theory of neutron evaporation from fission fragments. The theoretical results are compared with the experimental data for the spontaneous fission of ${}^{252}\mathrm{Cf}.$ The possibility of oscillative character of neutron average multiplicity versus fragment masses is discussed in terms of the neutron average binding energy for a given fragment mass.