Study on peak shape fitting method in radon progeny measurement.
Alpha spectrum measurement is one of the most important methods to measure radon progeny concentration in environment. However, the accuracy of this method is affected by the peak tailing due to the energy losses of alpha particles. This article presents a peak shape fitting method that can overcome the peak tailing problem in most situations. On a typical measured alpha spectrum curve, consecutive peaks overlap even their energies are not close to each other, and it is difficult to calculate the exact count of each peak. The peak shape fitting method uses combination of Gaussian and exponential functions, which can depict features of those peaks, to fit the measured curve. It can provide net counts of each peak explicitly, which was used in the Kerr method of calculation procedure for radon progeny concentration measurement. The results show that the fitting curve fits well with the measured curve, and the influence of the peak tailing is reduced. The method was further validated by the agreement between radon equilibrium equivalent concentration based on this method and the measured values of some commercial radon monitors, such as EQF3220 and WLx. In addition, this method improves the accuracy of individual radon progeny concentration measurement. Especially for the (218)Po peak, after eliminating the peak tailing influence, the calculated result of (218)Po concentration has been reduced by 21 %.
State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China.
Jinmin
J
Yang
Solid Dosimetric Detector and Method Laboratory, Beijing 102205, China.
Lei
L
Zhang
State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China.
Kadir
K
Abdumomin
State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China.
Yushi
Y
Tang
State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China qjguo@pku.edu.cn.
Qiuju
Q
Guo
D000396:Air Pollutants, Radioactive / Q000032:analysis*; D000465:Algorithms; D000512:Alpha Particles; D009716:Numerical Analysis, Computer-Assisted; D010363:Pattern Recognition, Automated / Q000379:methods*; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000379:methods*; D017687:Radon Daughters / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D000396:Air Pollutants, Radioactive; D017687:Radon Daughters