Study on source thickness and counting efficiency calibration for determining gross alpha activity in drinking water
10.3760/cma.j.issn.0254-5098.2021.12.010
- VernacularTitle:水中总α放射性测量的制源厚度及效率校准研究
- Author:
Yuxin QIAN
1
;
Liangliang YIN
;
Yuhan XIE
;
Yanqin JI
Author Information
1. 中国疾病预防控制中心辐射防护与核安全医学所 辐射防护与核应急中国疾病预防控制中心重点实验室，北京 100088
- Keywords:
Drinking water;
Radioactivity;
Gross α;
Mass thickness;
Counting efficiency
- From:
Chinese Journal of Radiological Medicine and Protection
2021;41(12):937-940
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To study the influence of source thickness and counting efficiency calibration on the measurement of gross alpha activity in water.Methods:241Am and natural uranium reference materials were spiked in drinking water to prepare source on a planchet with different thickness, for counting alpha activity on the planchet. Results:The effective thickness measured by spiking 241Am or uranium standard solution in water sample was consistent with the empirical value of 4 mg/cm 2. The alpha counting rate was in a linear increase trend from 2A-5A mg/cm 2 and was basically stable and no longer increase when thickness was higher than 10A mg/cm 2 (A was area of planchet). The result calculated by effective thickness method and thick source method were in good agreement when thickness was 10A mg/cm 2. Conclusions:In order to reduce the deviation of gross alpha counting rate caused by the source thickness and counting efficiency calibration, the source thickness is recommended to be 10A mg/cm 2.
