Prompt fission neutron spectra of 240Pu(n, F)

TL;DR

This paper predicts and analyzes the variation of prompt fission neutron spectra of 240Pu induced by neutrons up to 20 MeV, comparing it with spectra of other actinides and exploring the influence of exclusive neutron emissions.

Contribution

It introduces a comprehensive analysis of 240Pu prompt fission neutron spectra, incorporating data from related isotopes and predicting detailed spectral features and neutron emission characteristics.

Findings

240Pu(n, F) spectra are harder than 238U but softer than 239Pu.

Exclusive neutron spectra influence is significant at E=6-8 MeV.

Predicted spectra and neutron emissions align with existing cross-section data.

Abstract

Variation of fission neutron spectra of 240Pu (sf) and 240Pu (n, F) for E up to 20 MeV predicted.Features of angle-integrated prompt fission neutron spectra of 240Pu (n, F) stem from simultaneous analysis of data for 238U (n, F), 239Pu (n, F) and available data on 240Pu (n, F) prompt fission neutron spectra.The data on average energies of 240Pu (n, F) prompt fission neutron spectra support the approach pursued in case of 238U (n, F) and 239Pu (n, F). Soft influence of exclusive neutron spectra on prompt fission neutron spectra observed in case of 240Pu (n, F) and 240Pu (n, xnf) at E = 7-8 MeV. The largest relative amplitude of exclusive neutron spectra 240Pu (n, xnf) is envisaged at E = 6-6.25 MeV. Prompt fission neutron spectra of 240Pu (n, F) are harder than those of 238U (n,F), but softer than prompt fission neutron spectra for 239Pu(n, F). 240Pu (n, F) prompt fission neutron spectra 240Pu shape is rather close to that of 239Pu(n, F), though the contribution of pre-fission neutrons is relatively higher. Exclusive neutron spectra (n, xnf) are consistent with (n,F) cross sections of 237-240Pu(n, F), as well as neutron emissive spectra of 239Pu(n, xn) at E = 14 MeV. We predict the exclusive pre-fission neutron spectra, exclusive neutron spectra of (n,xn) reactions, average total kinetic energy TKE of fission fragments and products, partials of of average prompt fission neutron number and observed prompt fission neutron spectra.