重离子束水吸收剂量的电离法实验研究  

Experimental Study for Absorbed-dose to Water of Heavy Ion Beam via Ionization Method

作　　者：金孙均[1] 王坤[1] 王志鹏[1] 范耀东 杨小元[1] 张健[1] 贺鹏博[3] 申国盛 戴天缘 李强[3] JIN Sunjun;WANG Kun;WANG Zhipeng;FAN Yaodong;YANG Xiaoyuan;ZHANG Jian;HE Pengbo;SHEN Guosheng;DAI Tianyuan;LI Qiang(National Institute of Metrology,Beijing 100029,China;Beijing Institute of Metrology,Beijing 100029,China;Institute of Modern Physics,Chinese Academy of Science,Lanzhou 730000,China)

机构地区：[1]中国计量科学研究院,北京100029 [2]北京市计量检测科学研究院,北京100029 [3]中国科学院近代物理研究所,甘肃兰州730000

出　　处：《原子能科学技术》2020年第9期1722-1728,共7页Atomic Energy Science and Technology

基　　金：国家重点研发计划资助项目(2017YFF0205405,2016YFF0200804)。

摘　　要：重离子束水吸收剂量是开展重离子束治疗最基本的物理量。在开展重离子束水吸收剂量的量值复现研究前,需用间接测量的方法开展相关工作以熟悉实验条件。本文用传统电离法开展了能量400 MeV/u、具有6 cm展宽Bragg峰的碳离子束的水吸收剂量测量研究,并评价了重离子束条件下的相关电离室的极化、离子复合修正因子。在电离室的极化和离子复合修正项方面,重离子束水吸收剂量测量的相关不确定度分量显著大于^60Coγ辐射水吸收剂量的相关值。用不同电离室测量重离子束水吸收剂量的结果在不确定度允许的范围内符合。以电离室测量为基础,开展更深入的包括量热法绝对测量在内的辐射剂量学研究,对进一步优化重离子束水吸收剂量测量的不确定度至关重要。The absorbed-dose to water of heavy ion beam is a fundamental quantity for heavy ion therapy.It is necessary to perform the relevant work with in-direct measurement prior to the study of the reproduction for the absorbed-dose to water of heavy ion beam.The absorbed-dose to water of a carbon ion beam,whose incident energy was 400 MeV/u and spread-out Bragg peak was 6 cm,was studied with conventional ionization method.The correction factors of polarity and ion recombination for the ionization chambers were evaluated with the incident heavy ion beam.The uncertainty components for the measurement of the absorbed-dose to water of heavy ion beam are significantly larger than that of the ^60Coγradiation,in terms of the corrections for the polarity and ion recombination of the ionization chambers.The absorbed-dose to water of heavy ion beam deduced from different ionization chambers is consistent within the acceptance of uncertainty.Based on the measurement with ionization chambers,it is crucial to conduct more intensive research activities of radiation dosimetry including the absolute measurement with calorimetric facility,with the purpose of further optimizing the uncertainty in the measurement for the absorbed-dose to water of heavy ion beam.

关 键 词：重离子 水吸收剂量 电离法 修正因子 量热法 

分 类 号：R144.1[医药卫生—公共卫生与预防医学]