Construction of γ Energy Spectrum Response Function Matrix in NaI Detector

Abstract

In energy spectrum analysis, establishing accurate spectral response function plays a key role in the application of this technology. Generally, the response function of the detector is calculated by using experimentally measured data. This method needs to decompose the gamma spectrum into a single energy spectrum and then perform data fitting to obtain a response function. In reality, a sufficient number of gamma radiation sources cannot be found to establish an accurate response function. However, a simple theoretical calculation is difficult because the secondary process of gamma photons is complicated. Therefore, it is necessary to use simulation software. In this paper, 43 different energy gamma spectra are simulated, and the required data are extracted by function fitting, formula calculation, etc. The mathematical laws and physical principles between the data are analyzed. The incident ray energy is the main variable, the peak value of the full energy, the count ratio of the full energy and peak, the coefficient of the peak width of the full energy, the Compton side energy and other parameters are used as the response variables to establish an accurate single-energy gamma spectrum response matrix. It has important guiding significance for future research on the energy spectrum of NaI detector.