The Study of Zinc Sulphide Scintillator for Fast Neutron Radiography

Fast neutron radiography is a promising application for accelerators. The potential effectiveness of this technique depends on the development of suitable imaging detectors for fast neutrons. Zinc sulphide based scintillators have the largest light output per event in the family of imaging scintillators used so far in fast neutron radiography. This paper investigated different aspects of this scintillator in order to determine the factors which might affect the light output. A mathematical model was established to estimate effectiveness of this scintillator. Zinc sulphide screens were prepared with ZnS particles of different concentration in polypropylene matrix. A 14MeV fast neutron source was used in the experiments. The light output was detected using a CCD camera or a film coupled to the scintillator screen. The results showed that the optimum scintillators is 3-mm in thickness with the weight ratio of 1:1 to 2:1 for ZnS and polypropylene.