Characterization of a scintillating lithium glass ultra-cold neutron detector

TL;DR

This paper characterizes a $^{6}$Li glass scintillation detector for ultra-cold neutrons, demonstrating high background rejection efficiency and comparing its performance with a commercial detector at PSI.

Contribution

It provides a detailed performance assessment of a $^{6}$Li glass scintillation detector for ultra-cold neutrons, including efficiency and background rejection capabilities.

Findings

Background rejection efficiency estimated at 99.7%.

Detector efficiency around 89.7% for varying neutron rates.

Comparison with a commercial detector shows competitive performance.

Abstract

A $^{6}$Li glass based scintillation detector developed for the TRIUMF neutron electric dipole moment experiment was characterized using the ultra-cold neutron source at the Paul Scherrer Institute (PSI). The data acquisition system for this detector was demonstrated to perform well at rejecting backgrounds. An estimate of the absolute efficiency of background rejection of $99.7\pm0.1$% is made. For variable ultra-cold neutron rate (varying from $<$1 kHz to approx. 100 kHz per channel) and background rate seen at the Paul Scherrer Institute, we estimate that the absolute detector efficiency is $89.7^{+1.3}_{-1.9}$%. Finally a comparison with a commercial Cascade detector was performed for a specific setup at the West-2 beamline of the ultra-cold neutron source at PSI.