作者：张园月, 陈晓渊, 鄢玲, 黄杨, 林滔
作者单位：中国测试技术研究院, 四川成都 610021
关键词：平板电离室; 辐射质; 吸收剂量; 电子束; 校准因子
摘要：
基于平板电离室的结构和物理特性,比圆柱形电离室更适用于电子束的水中吸收剂量测量,特别是在能量相对较低的电子束测量中更具优越性。介绍了基于两种量传体系的平板电离室溯源方式,提出了在现场如何利用已知校准因子的参考电离室得到平板电离室的校准因子的方法。在国内尚未建立水吸收剂量量传体系时,借助该方法可获得平板电离室水吸收剂量校准因子,据此按照TRS-398报告开展高能电子束水中吸收剂量测量,进一步减小测量结果的不确定度。
Parallel-plane chamber calibration for measuring medical electron beam absorbed dose
ZHANG Yuan-yue, CHEN Xiao-yuan, YAN Ling, HUANG Yang, LIN Tao
National Institute of Measurement and Testing Technology, Chengdu 610021, China
Abstract: Parallel plane chamber, in view of its structure and physical properties, has more advantages in the absorbed dose measurement of electron beam in water compared with the cylindrical ionization chamber, especialy in the measurement of relatively low energy electron beam. In this paper, the traceability of plate ionization chambers is presented according to two transferring systems, and an approach using the known calibration factor of reference chamber to obtain the calibration factor of the water absorbed dose of plane parallel chambers in the condition that there is no corresponding transferring system in our country. Thus, the measurement uncertainty would be further reduced if the absorbed dose of the high-energy electron beam in water is measured in accordance with TRS-398 and this method.
Keywords: Parallel-plane chamber; Radiation quality; Absorbed dose; Electron beam; Calibration factor
2009, 35(3): 24-27 收稿日期: 2008-9-17;收到修改稿日期: 2008-12-5
基金项目: 国家科技条件平台项目(2005DKA10709)
作者简介: 张园月(1965-),男,四川平昌人,高级工程师,主要从事电离辐射计量检测与研发工作。
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