⁶⁰coγ射线空气比释动能绝对测量中国测试科技资讯平台 -凯发真人

作者：杨乾¹, 张园月¹, 刘操¹, 许诗朦¹, 张晓栋¹, 张秋辰²

作者单位：1. 中国测试技术研究院，四川 成都 610000;
2. 四川中测辐射科技有限公司，四川 成都 610000

关键词：空气比释动能;石墨空腔电离室;相对标准不确定度;绝对测量;电离辐射

摘要：

为解决⁶⁰coγ射线空气比释动能量值溯源与传递的问题以及进一步提升量值溯源与传递能力，中国测试技术研究院采用石墨空腔电离室以布拉格-格雷理论为基础测量光子辐射空气比释动能的方法建立⁶⁰coγ射线空气比释动能绝对测量装置，复现⁶⁰coγ射线空气比释动能，其量值复现的相对标准不确定度为0.2%。文中阐述和研究石墨空腔电离室结构和⁶⁰coγ射线空气比释动能量值复现的影响因子。为进一步验证⁶⁰coγ射线空气比释动能量值复现结果的准确性与一致性，中国测试技术研究院与加拿大国家实验室nrc (national recerche coucil) ，就 ⁶⁰coγ射线空气比释动能量值复现进行测量比对，比对结果在相对标准不确定度0.52%以内一致，e_n值为–0.07。

absolute measurement of air kerma for ⁶⁰co gamma ray
yang qian¹, zhang yuanyue¹, liu cao¹, xu shimeng¹, zhang xiaodong¹, zhang qiuchen²
1. national institute of measurement and testing technology, chengdu 610000, china;
2. sichuan zhongce radiation technology co., ltd., chengdu 610000, china
abstract: in order to solve the problem of traceability and transfer of ⁶⁰co γ - ray air kerma and improve the traceability and transfer ability, national institute of measurement and testing technology (nimtt) established an absolute measurement device of ⁶⁰co γ - ray air kerma by using graphite cavity ionization chamber based on bragg-gray theory. air kerma in ⁶⁰co gamma ray was measured absolutely by graphite cavity ionization chamber, the combined relative standard uncertainty is 0.2%. the structure of graphite cavity ionization chamber and the correction factor of measurement results were described and researched. a comparison was made between nimtt and national research council (nrc). the results were agreement with the relative standard uncertainty of 0.52%. the value of e_n was -0.07.
keywords: air kerma;graphite cavity ionization chamber;relative standard uncertainty;absolute measurement;ionizing radiation
2022, 48(6):45-50  收稿日期: 2020-11-09;收到修改稿日期: 2021-04-28
基金项目: 科技创新基地（平台）和人才计划（2020jdky0001）
作者简介: 杨乾（1986-），男，宁夏吴忠市人，助理研究员，主要从事辐射物理与医学物理领域的计量测试与研究工作
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