Technical research on positional offset correction and spectrum restoration of gamma energy channels using a CeBr3 detector

Abstract

In environmental gamma radioactivity measurements, the measurement of potassium, uranium, and thorium is crucial for strategic resource exploration, geological surveys, and environmental background investigations. This study focused on CeBr₃ detector measurements and discovered that artificial radionuclides affected the intrinsic peaks and peak positions in the regions of interest for potassium, uranium, and thorium, resulting in offsets and distortions in the energy spectrum. Based on principal component analysis and linear regression, the study corrected the interference of artificial radionuclides in the measurements of potassium, uranium, and thorium. The results demonstrated that the peak offset was effectively corrected, with a maximum offset of 0.8 channels, compared to a maximum offset of 6.5 channels before correction. Additionally, correcting the peak area changes yielded better results, effectively reducing the errors in peak area calculations. Specifically, the error in peak area calculations was reduced from 10.52 % to 1.62 % for potassium, from 13.48 % to 1.79 % for uranium, and from 7.00 % to 4.96 % for thorium. The study successfully mitigated the peak position shifts and peak area variations caused by the counting contributions of artificial radionuclide ¹³⁷Cs to the regions of interest for potassium, uranium, and thorium, thereby improving the accuracy of peak area calculations. The analytical method effectively addresses the issue of gamma energy spectrum offset and deformation, holding significant research significance and practical value in various applications, including aerial gamma energy spectrum measurements, environmental radioactivity measurements, geological exploration, and mineral investigations.