Counting loss correction in 37Ar activity measurement based on Geant4 simulation
- VernacularTitle:基于Geant4模拟37Ar活度测量计数损失的修正方法
- Author:
Shuying KONG
1
;
Baolu YANG
1
;
Rensheng WANG
2
;
Ming ZHANG
3
;
Tianxiang LU
1
;
Fei TUO
1
Author Information
- Publication Type:Journal Article
- Keywords: 37Ar; Geant4; Proportional counter; Detection efficiency; Counting loss correction
- From: Chinese Journal of Radiological Health 2023;32(2):93-97
- CountryChina
- Language:Chinese
- Abstract: Objective To correct the counting loss of 37Ar below the activity threshold during the measurement of the absolute activity of the inert radioactive gas 37Ar using the proportional counter filled with gas. Methods Monte Carlo simulation with Geant4 was performed to establish a proportional counter model and output the energy deposition spectrum of 37Ar, which were used to simulate and analyze the causes and correction of counting loss. Results The photon detection efficiency was only 38.7% at 60 kPa. The counting loss was mainly caused by the wall effect produced by the photons, which could be reduced by increasing the gas pressure and corrected by extrapolation. The influence of wall effect at 100 kPa was 4.4%, and the deviation between simulation and experiment was < 0.6%. Conclusion A factor could be calculated by Geant4 simulation for the correction of counting loss, thus achieving the accurate measurement of 37Ar activity by proportional counter.
