Characterization of the thickness of dead layer and cold finger for portable HPGe γ-spectrometer

• Published in: Radiation physics and chemistry (Oxford, England : 1993) England : 1993), 2023-03, Vol.204, p.110665, Article 110665
• Main Authors: Wu, Zeqian, Wang, Bairong, Sun, Jian
• Format: Article
• Language: English
• Subjects: Dead layer; Detection efficiency; HPGe γ detector
• ISSN: 0969-806X; 1879-0895
• DOI: 10.1016/j.radphyschem.2022.110665

The internal structure of the HPGe γ-spectrometer will change with increasing use time, which will significantly impact the accuracy of the modelling simulation results. In this paper, the characterization method of the structural parameters of the HPGe γ-spectrometer is investigated, and the characterization results are presented. Experimental measurements and Monte Carlo simulations are performed at four different positions using six radioactive point sources covering low, medium, and high energies of γ-rays, respectively. The thickness of the dead layer on the front and lateral surface and cold finger on the front and lateral surface are adjusted sequentially according to the characterization algorithm. The thickness of the dead layer on the front surface is corrected to 0.21 cm, and the dead layer on the lateral surface is corrected to 0.08 cm. The thickness of the cold finger on the front surface and lateral surface does not change. The maximum relative deviation of the Monte Carlo simulation results from the experimental results was reduced from 72.7% before correction to 4.3%. •Characterization of the thickness of dead layer and cold finger on the front and lateral of a HPGe γ spectrometer.•Design a characterization algorithm and implement it through MC simulations and experiments.•The characterization can be considered valid when the maximum relative error is less than 5%.