Monte Carlo simulation of prompt gamma-ray spectra from depleted uranium under D-T neutron irradiation and electron recoil spectra in a liquid scintillator detector

TL;DR

This paper presents a two-step Monte Carlo simulation method to efficiently and reliably calculate prompt gamma-ray and electron recoil spectra from depleted uranium under D-T neutron irradiation, validated against experimental data.

Contribution

The study introduces a two-step Monte Carlo approach combining MCNP5 and EGSnrc codes to improve computational efficiency and accuracy in gamma-ray and electron recoil spectrum simulations.

Findings

Simulations agree well with experimental data in the 0.4-3 MeV gamma-ray energy range.

The method accurately predicts electron recoil spectra below 4 MeVee.

The two-step approach enhances reliability and reduces computation time.

Abstract

To overcome the problem of inefficient computing time and unreliable results in MCNP5 calculation, a two-step method is adopted to calculate the energy deposition of prompt gamma-rays in detectors for depleted uranium spherical shells under D-T neutrons irradiation. In the first step, the gamma-ray spectrum for energy below 7 MeV is calculated by MCNP5 code; secondly, the electron recoil spectrum in a BC501A liquid scintillator detector is simulated based on EGSnrc Monte Carlo Code with the gamma-ray spectrum from the first step as input. The comparison of calculated results with experimental ones shows that the simulations agree well with experiment in the energy region 0.4-3 MeV for the prompt gamma-ray spectrum and below 4 MeVee for the electron recoil spectrum. The reliability of the two-step method in this work is validated.