Comparison of neutron sensitive scintillators for use with a solid-state optical detector

The detection of illicit nuclear sources and SNM requires an ubiquitous network of sensors. While 3He proportional counters are excellent neutron detectors, there is an insufficient global supply of 3He to create the required number of detectors. Alternatives to 3He must be efficient, insensitive to gamma radiation, easily manufactured, rugged, and inexpensive to enable the procurement of a large numbers of sensors. The use of a high sensitivity solid-state optical detector coupled to scintillation materials, loaded with a neutron absorber such as 6Li or 10B, can fulfill these design constraints. In this work, we compare the properties of neutron-sensitive scintillation materials utilizing Monte Carlo simulations and experiments. Cs2LiLaBr6:Ce is compared to commercially available boron-loaded plastic scintillators and 3He tubes. The scintillators are compared for neutron detection efficiency, limitations on size, gamma-rejection ratio, neutron detection limits, manufacturing cost, and availability for mass-production.