Characterization of a CLYC detector for underground experiments

TL;DR

This paper thoroughly characterizes a CLYC detector's performance for underground experiments, highlighting its capabilities and limitations in gamma-ray and neutron detection through experimental and simulation methods.

Contribution

It provides comprehensive experimental data and Monte Carlo simulations for a large CLYC detector, advancing understanding of its suitability for low-background applications.

Findings

Achieved 4.7% energy resolution at 662 keV

Neutron/gamma separation figure of merit of 4.2

Identified intrinsic background contamination in the detector

Abstract

Large size detectors based on Cs2LiYCl6:Ce (CLYC) are capable of performing a combined $\gamma$-ray and neutron spectrometry and constitute a promising technology for a wide range of applications in nuclear and high energy physics. Due to their novelty, the comprehensive characterization of the performance of individual CLYC detectors is of great importance for determining their range of applicability. In this work we report on a wide series measurements performed with a commercial 2"x2" CLYC crystal. Good energy and timing resolution values of 4.7% (@ 662 keV) and 1340 ps (FWHM), respectively, were achieved, and a neutron/$\gamma$ separation figure of merit value of 4.2 was obtained. A dedicated measurement for investigating the intrinsic background of the detector was performed at the Laboratorio Subterr\'aneo de Canfranc (Spain). It evidenced a sizeable contamination in the detector materials which poses limits in the use of CLYC in low background experiments. In addition, detailed Monte Carlo simulations with the GEANT4 toolkit were performed for modeling the response function of the CLYC detector to gamma-rays. An excellent agreement with the experimental data has been achieved.