基于<sup>90</sup>Sr源β射线的外推电离室入射窗修正因子

吴琦; 李德红; 黄建微; 郝艳梅; 周青芝

doi:10.7538/yzk.2018.youxian.0465

基于⁹⁰Sr源β射线的外推电离室入射窗修正因子

1.
南华大学核科学技术学院,湖南衡阳421001
2.
中国计量科学研究院,北京100029

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出版历程
- 刊出日期: 2019-05-19

Extrapolation Chamber Entrance Window Correction Factor on ⁹⁰Sr β Ray Radiation Field

1.
School of Nuclear Science and Technology, University of South China, Hengyang 421001, China
2.
National Institute of Metrology, Beijing 100029, China

摘要

摘要: 为实现外推电离室对β辐射吸收剂量的准确测量，对影响外推电离室入射窗修正因子k_wi的主要量进行了研究。实验测量了外推电离室不同极间距和不同源探距（源到外推电离室入射窗表面的距离）下的k_wi。研究结果表明，在源探距不变的条件下，k_wi随电离室极间距的增大而减小；在电离室极间距为3 mm的条件下，k_wi随源-探距的增大而减小。利用蒙特卡罗模拟计算出不带展平过滤器、源探距为30 cm、电离室极间距为3 mm时，k_wi为1.0845，与实验测量结果比较，其相对偏差为0.11%。因此，在给出k_wi的同时，应提供相应的源-探距和电离室极间距。
- ⁹⁰Sr源 ,
- β射线 ,
- 外推电离室 ,
- 修正因子 ,
- 蒙特卡罗
Abstract: In order to achieve accurate measurement of the absorbed dose of beta radiation, the main influence factors of the extrapolation chamber entrance window correction factor k_wi were studied. k_wi at different cavity lengths and different sourcedetection distances was measured by experiments. The results show that the correction factor k_wi with the same source-detection distance decreases with the increase of the cavity length. And k_wi decreases with the increase of the source-detection distance when the cavity length is 3 mm. The calculated k_wi without flattened filter at source-detection distance of 30 cm and cavity length of 3 mm was simulated using Monte Carlo method. The simulation result is 1.084 5, which differs from the experiment result by 0.11%. Therefore, in addition to the correction factor k_wi, corresponding source-detection distance and cavity length should be supplied.
- ⁹⁰Sr source ,
- β ray ,
- extrapolation chamber ,
- correction factor ,
- Monte Carlo

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参考文献(11)

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