Multilayer High-Performance Neutron Scintillation Counter Based on SiPM and an Organic Light Guide

New neutron scintillation detectors based on silicon photomultipliers and organic-glass light guides are described. This type of detector may become an alternative to gas-filled detectors, in which the medium used (He-3) is expensive. In this work, ZnS:(LiF)-Li-6(Ag) is used as a scintillator with a calculated efficiency of 42% for thermal neutrons. An optically transparent plastic is used as the light guide. The dimensions of the finished detector are 60 x 5 x 5 mm. The thickness of the scintillator layers is fixed and equal to 0.5 mm. The fiber thickness is varied in the range from 0.3 to 1.8 mm depending on the number of scintillator layers; it is limited by the total detector thickness. A method for manufacturing and joining together such scintillation detectors is described. The first results of testing neutron counters with different numbers of scintillator layers are presented. When using two scintillator layers, the efficiency of this neutron-detector type is 42%. With an increase in the number of scintillator layers to five, the efficiency increased to 90%.