Next-Generation Neutron Detection Using a 6Li Glass Scintillator Composite

Abstract Neutron detectors play a crucial role in fundamental science, nuclear security, safeguards, and civil applications. Traditionally, 3 He-filled gas proportional counters are the gold standard for thermal neutron detection, prized for their efficiency, neutron/gamma discrimination, and stability—however, the scarcity of 3 He has prompted the search for alternatives. Here, we introduce an innovative neutron detector design based on a scintillating composite consisting of 6 Li-enriched glass scintillator particles dispersed in an organic matrix. A detector consisting of this scintillating composite, photomultiplier tubes (PMTs) for optical detection, and electronics for reading out the PMT signal in both pulse and current modes was prototyped and characterized using various neutron and gamma sources. The prototype (69.7 mm diameter and 260 mm length) achieves a detection efficiency of 6.7%, a die-away time of 10.5 µs, a negligible gamma misidentification probability (for 137 Cs and 60 Co gamma sources), and response linearity up to at least 3.7×10 6 incident neutrons/s established via an innovative cross-calibration technique. This novel detector holds the potential to outperform traditional 3 He-gas-based neutron systems, offering a viable alternative amidst the ongoing 3 He shortage and promising advancements in neutron detection technology. LA-UR-24-20569