Study on Response Function Model for γ-ray Scintillation Detector

The detector response function (DRF) model of scintillation over the range of incident γ-ray energy from 0.05 MeV to 1.5 MeV was established and applied to fit radiation source spectra. Each function for describing the feature of γ-ray spectra is based on the analysis of fundamental interaction mechanism. These functions were combined to form a DRF model to fit ²²Na, ⁶⁰Co, ¹³⁷Cs, ²³⁸Pu experiment spectra by weighted least square fitting method, and nonlinear parameters in this model were obtained simultaneously which are dependent on the source energy. The validity of DRF model was demonstrated by fitting ¹⁵²Eu spectra measured by CsI(Tl) detector. The result shows that this model is useful to analyze γ-ray spectrum.