Preparation and characterization of 6LiF/ZnS(Ag) scintillator with varying granulometry

Abstract

The effect of the dispersity of 6LiF and ZnS(Ag) powders on the performance of a 6LiF/ZnS(Ag) composite scintillator with a mass ratio of 6LiF/ZnS(Ag)/binder component mass ratio of 1 6LiF:4ZnS(Ag):2.1 binder was studied. It has been established that for a singlelayer 6LiF/Zn S(Ag) composite with a thickness of 0.2 mm, the best light output and thermal neutron detection efficiency (~29%) is provided at ratios of 1 to (10.3-13.3) for 6LiF and ZnS(Ag) grain size and (550-1150) to 1 for their number of grains respectively. Outside these optimal ratios, the detection efficiency drops to 20-22%. When the ratio of the number of the 6LiF and ZnS(Ag) grains is below optimal, the detection efficiency decreases due to a decrease in the probability of neutron capture by a reduced number of 6Li nuclei. A significant excess of 6LiF increases both the neutron capture probability and the absorption probability of the charged products of the neutron capture reaction in the same 6LiF converter, without causing scintillations in ZnS(Ag). It has been shown that a scintillation detector constructed from five 6LiF/ZnS(Ag) layers, alternating with four organic glass plates acting as light guides ensures a thermal neutron detection efficiency of 75%.