Simulation of the 2E Technique on neutron multiplicity measurement as a function of fragment mass in spontaneous fission of 252Cf

TL;DR

This paper presents a Monte Carlo simulation of the 2E technique to measure prompt neutron multiplicity in spontaneous fission of 252Cf, revealing discrepancies between simulated and theoretical curves due to mass relationship inaccuracies.

Contribution

It introduces a simulation approach combining experimental and model data to analyze the 2E technique's effectiveness in neutron multiplicity measurement.

Findings

Simulated and experimental curves show different maxima at A=122 and A=118.

Discrepancies are linked to inaccuracies in mass relationship assumptions.

The simulation highlights potential improvements in data processing methods.

Abstract

A Monte Carlo simulation algorithm to investigate the measurement of the average prompt neutron multiplicity as a function of pre-neutron mass, for fragments from the spontaneous fission of 252Cf is presented. The input data consist of experimental measurements of the kinetic energy and mass distributions obtained by Gook et al. and the values calculated using the FIFRELIN model by Piau et al. We analyze the output curve obtained by simulation of the 2E technique, which should ideally match the theoretical curve. However, we find that the simulated as experiential curve exhibits a maximum value at A=122, close to mass symmetry, while the pre-neutron curve has a maximum at A=118. Additionally, we observe that que the simulated as pre neutron values are higher than the theoretical values for A<90 and A>162, respectively. We attribute this discrepancy to inaccuracies in the relationship between provisional mass and the pre-neutron mass used in the 2E technique for data processing in each fission event.