Investigation into the potential of GAGG:Ce as a neutron detector

Abstract

In this work we investigate the potential use as a thermal neutron detector of cerium-doped gadolinium aluminium gallium garnet (GAGG:Ce) coupled to a silicon photomultiplier (SiPM). The response to thermal neutrons has been measured, with two strong low energy neutron-indicative peaks clearly identifiable below 100 keV and additional γ peaks at higher energies. The neutron-related peaks are produced by a combination of contributions from excited states of the two isotopes 156 Gd and 158 Gd which can be clearly resolved in our GAGG scintillation detector. In particular, two peaks due to neutron-induced γ-ray emission are observed at approximately 82 keV and 260 keV, with best achieved energy resolutions of 24.1 ± 0.2% and 22.7 ± 0.7% respectively. Three different scintillator volumes (0.1 cm 3 , 0.4 cm 3 , and 1 cm 3 ) were investigated and the respective results for each configuration will be presented. Our findings show that a GAGG-SiPM based detector can be used as a compact, efficient thermal neutron detector in a low γ-ray contamination environment.