Fig. 1: Schematic illustration of the operating principle of the ⁶Li-glass scintillator composite neutron detector.

a Fast incident neutrons (red arrow) are moderated within the matrix consisting of ⁶Li glass (GS20^TM) particles suspended in mineral oil, where they undergo capture in the ⁶Li glass particle through the ⁶Li(n,α)³H nuclear reaction. Subsequently, the reaction products produce scintillation light within the ⁶Li glass particle, which propagates (green arrows) to the two photomultipliers (PMT) for detection. Electric signals from the PMTs are pre-amplified and shaped, followed by digitization and summing. b The summed signals are sorted in a multichannel analyzer to produce a pulse height histogram. The channel number is proportional to pulse height. In this pulse-height spectrum, the ⁶Li neutron capture peak is evident and well separated from the low amplitude signal due to gamma interactions.