医用电子束水吸收剂量测量及其不确定度讨论

doi:10.3969/j.issn.1000-1158.2023.12.16

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摘要目前医用电子束水吸收剂量测量不确定度超过3%,很难满足临床治疗和医用电子加速器辐射源检定规程的要求。中国计量科学研究院采用水量热法开展了电子束辐射剂量学的研究,实现了电子束水吸收剂量绝对测量相对标准不确定度为0.35%,同时也开展了医用电子束的同质溯源工作,总结了电子束水吸收剂量测量的5个方案,相对标准不确定度包含最高的3.7%和最低的1.4%。为方便临床电子束水吸收剂量测量,给出了电离室剂量计选取、送检和使用不同校准系数的注意事项。

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	王志鹏
	王坤
	金孙均
	杨小元
	齐雅平
	黄骥
	刘福斌

关键词 ：电离辐射, 医用电子束, 水吸收剂量, 电离室剂量计, 校准系数

Abstract：The measurement uncertainty of absorbed dose to water, Dw, in medical electron beams exceeds 3%, which is difficult to meet the requirements of clinical treatment and verification regulation of medical electron accelerator radiation source. The research on measuring electron beam radiation dosimetry using water calorimetry was carried out by the National Institute of Metrology (NIM), which realized the direct measurement of the Dw, with a relative standard uncertainty of 0.35%. At the same time, the research on the homogenous traceability of medical electron beams have also been carried out. Five schemes for measuring the absorbed dose to water in electron beams have been summarized. The relative standard uncertainty includes the highest 3.7% and the lowest 1.4%. In order to facilitate the measurement of the Dw in clinical electron beams, some suggestions on the selection and calibration methods of ionization chambers were provided, and precautions for different calibration coefficients were emphasized.

Key words： Ionizing radiation medical electron absorbed dose to water;ionization chamber dosimeter;calibration coefficient

收稿日期: 2022-12-29 发布日期: 2023-12-27

PACS:

TB98

基金资助:国家重点研发计划(2021YFF0603600)

通讯作者: 王坤(1980-)男,辽宁朝阳人,中国计量科学研究院研究员,博士,主要从事辐射剂量学研究。Email:wangkun@nim.ac.cn E-mail: wangkun@nim.ac.cn

作者简介: 王志鹏(1991-),男,安徽太和人,中国计量科学研究院助理研究员,博士,主要从事水吸收剂量基标准相关研究。Email:wangzp@nim.ac.cn

引用本文:

王志鹏,王坤,金孙均,杨小元,齐雅平,黄骥,刘福斌. 医用电子束水吸收剂量测量及其不确定度讨论[J]. 计量学报, 2023, 44(12): 1897-1903.
WANG Zhi-peng,WANG Kun,JIN Sun-jun,YANG Xiao-yuan,QI Ya-ping,HUANG Ji,LIU Fu-bin. Measurements of Absorbed Dose to Water in Medical Electron Beams and Discussion of Its Uncertainty. Acta Metrologica Sinica, 2023, 44(12): 1897-1903.

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http://jlxb.china-csm.org:81/Jwk_jlxb/CN/10.3969/j.issn.1000-1158.2023.12.16 或 http://jlxb.china-csm.org:81/Jwk_jlxb/CN/Y2023/V44/I12/1897

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