Prediction of the Prompt Neutron Multiplicity Distribution ν(A) for ²³⁵U(n,f) and ²³⁹Pu(n,f) in the Incident Energy Range of Multichance Fission

Abstract

Measurements of fission fragment data at incident energies (En) up to several tens of MeV require prompt neutron multiplicity distribution ν(A) to determine the preneutron fragment properties. Those ν(A) data are not readily experimentally available. Consequently, model predictions of ν(A) at En where multichance fission occurs are needed. The Point-by-Point model of prompt emission provides the individual ν(A) of compound nuclei of the main and secondary nucleus chains that are undergoing fission at any En. Total ν(A) calculations for n + ²³⁵U and n + ²³⁹Pu are presented together with systematic behaviors of individual ν(A) with increasing energy.

Keywords:

• Prompt emission in fission
• prompt fission neutron distributions
• average number of prompt neutrons
• fission fragment distributions

Acknowledgments

A part of this work was done in the frame of the Romanian Exploratory Research Project PCE-2016-0014.

One of the authors (A.T.) acknowledges the short-term visit support by the European Commission within the framework of the CHANDA program.