CTOF Measurements and Monte Carlo Analyses of Neutron Spectra for the Backward Direction from a Copper Target Irradiated with 800, 1000, and 1200 MeV Protons

TL;DR

This study employs the CTOF technique to measure neutron spectra from a copper target irradiated with high-energy protons and compares these measurements with predictions from multiple Monte Carlo simulation codes, assessing their accuracy.

Contribution

It provides high-precision neutron spectrum measurements at backward angles and evaluates the performance of various Monte Carlo codes in predicting these spectra.

Findings

All tested codes reasonably agree with experimental data.

Code accuracy varies with neutron energy and proton incident energy.

The study highlights strengths and limitations of current simulation models.

Abstract

A calorimetric-time-of-flight (CTOF) technique was used for real-time, high-precision measurement of the neutron spectrum at an angle of 175 deg from the initial proton beam direction, which hits a face plane of a cylindrical copper target of 20 cm in diameter and 25 cm thick. A comparison was performed between the neutron spectra predicted by the MARS, RTS&T, GEANT4, and the MCNP6 codes and that measured for 800, 1000, and 1200 MeV protons. The transport codes tested here describe with different success the measured spectra, depending on the energy of the detected neutrons and on the incident proton energy, but all the models agree reasonably well with our data.