High-efficiency scintillation detector for thermal and high-energy neutrons and gamma radiation

Subcriticality experiments require high-efficiency radiation detectors that are sensitive to neutrons (thermal and fast) over a wide energy range and to gamma radiation. A scintillation detector design that meets these criteria is described. It consists of two scintillators assembled on a single photomultiplier tube. One scintillator is a glass, loaded with lithium enriched in /sup 6/Li, and has high efficiency for low-energy neutrons. The second scintillator is a plastic having very good efficiency for higher-energy neutrons. Efficiency values are reported for various neutron energy ranges and for gamma radiation.<>