A First Comparison of the responses of a He4-based fast-neutron detector and a NE-213 liquid-scintillator reference detector

TL;DR

This study compares a novel helium-4 based fast-neutron detector with a traditional NE-213 liquid scintillator, focusing on their ability to discriminate neutrons from gamma-rays using pulse-shape analysis.

Contribution

It provides the first comparison of pulse-shape discrimination capabilities between a helium-4 based detector and a NE-213 scintillator for neutron and gamma-ray detection.

Findings

The helium-4 detector shows excellent neutron/gamma discrimination above 750 keVee.

The NE-213 detector produces a wide range of scintillation yields for gamma-rays.

The helium-4 detector's maximum scintillation yield for gamma-rays is limited to 750 keVee.

Abstract

A first comparison has been made between the pulse-shape discrimination characteristics of a novel $^{4}$He-based pressurized scintillation detector and a NE-213 liquid-scintillator reference detector using an Am/Be mixed-field neutron and gamma-ray source and a high-resolution scintillation-pulse digitizer. In particular, the capabilities of the two fast neutron detectors to discriminate between neutrons and gamma-rays were investigated. The NE-213 liquid-scintillator reference cell produced a wide range of scintillation-light yields in response to the gamma-ray field of the source. In stark contrast, due to the size and pressure of the $^{4}$He gas volume, the $^{4}$He-based detector registered a maximum scintillation-light yield of 750~keV$_{ee}$ to the same gamma-ray field. Pulse-shape discrimination for particles with scintillation-light yields of more than 750~keV$_{ee}$ was excellent in the case of the $^{4}$He-based detector. Above 750~keV$_{ee}$ its signal was unambiguously neutron, enabling particle identification based entirely upon the amount of scintillation light produced.