Calculation of efficiency and resolution of a hexagonal NaI(Tl) detector as a function of source position

Most gamma-ray scintillation detectors currently in use are made from inorganic materials that have a relatively high electron density. Quite often they are used to build multidetector systems that provide high scintillation light output. The performance of a gamma radiation detector (its detection efficiency) depends on the shape and size of the crystal, as well as on the source-to-detector geometry used. The NaI(Tl) gamma detector exhibits moderate energy resolution but relatively high gamma-ray detection efficiency and fast time response. In this work, the efficiency and resolution of a scintillation hexagonal detector are studied to optimize its response function. This type and size of scintillator were selected to construct a budget-friendly, reconfigurable, easy-to-maintain multidetector system for registering gamma-rays following fission, capture, and inelastic neutron scattering reactions, with reasonably good energy and time resolutions The research results made it possible to establish a geometric solid angle that increases the efficiency of recording gamma-ray radiation of the hexagonal NaI(Tl) scintillation probe under study.