| 室内环境中子能谱及剂量率的多球谱仪测量 |
| 胡庆东1, 曾志1, 马豪1, 程建平1, 李君利1, 张辉1, 王鑫1, 武祯1,2 |
| 1. 清华大学 工程物理系, 粒子技术与辐射成像教育部重点实验室, 北京 100084; 2. 同方威视股份有限公司, 北京 100084 |
| Measurement of indoor natural neutron spectrum with a Bonner sphere spectrometer |
| HU Qingdong1, ZENG Zhi1, MA Hao1, CHENG Jianping1, LI Junli1, ZHANG Hui1, WANG Xin1, WU Zhen1,2 |
| 1. Key Laboratory of Particle and Radiation Imaging of the Ministry of Education, Department of Engineering Physics, Tsinghua University, Beijing 100084, China; 2. Nuctech Company Limited, Beijing 100084, China |
摘要:
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| 摘要利用自主研发的多球中子谱仪对北京市某室内环境中子能谱及剂量率进行了测量。从中子能谱获得了能量低于20 MeV的环境中子注量率为2.83×10-3cm-2·s-1, 估算出环境中子总注量率为3.54×10-3cm-2·s-1; 利用中子注量与周围剂量当量转换系数计算出了能量低于20 MeV中子周围剂量当量率为(1.5±0.1) nSv/h, 总中子周围剂量当量率为(2.1±0.1) nSv/h, 与中子剂量仪测量值(2.3±0.2) nSv/h基本一致。该文测量结果与相近纬度比较相差不多, 可以为评估北京室内环境中子剂量提供参考。 | |||
| 关键词 ：多球中子谱仪,环境中子,能谱,遗传算法,中子剂量 | |||
| Abstract：A Bonner sphere spectrometer was used to measure indoor natural neutron spectra in Beijing with the neutron energy spectrum obtained using an unfolding procedure with a genetic algorithm. The spectra and fluence-to-dose conversion coefficients gave a neutron flux of 2.83×10-3 cm-2·s-1 and a neutron ambient dose equivalent of (1.5±0.1) nSv/h for neutron energy below 20 MeV. The total neutron flux was 3.54×10-3 cm-2·s-1 and the total neutron ambient dose equivalent was (2.1±0.1) nSv/h which are comparable with the dose of (2.3±0.2) nSv/h measured by a 3He neutron monitor. The results are consistent with other measurements at similar latitudes, which verifies the reliability of this instrument and the indoor neutron dose equivalent in Beijing. | |||
| Key words：Bonner sphere spectrometernatural neutronsspectrumgenetic algorithmneutron dose | |||
| 收稿日期: 2014-01-14 出版日期: 2016-01-12 | |||
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| 通讯作者:曾志,副研究员,E-mail:zengzhi@mail.tsinghua.edu.cnE-mail: zengzhi@mail.tsinghua.edu.cn | |||
| 引用本文: |
| 胡庆东, 曾志, 马豪, 程建平, 李君利, 张辉, 王鑫, 武祯. 室内环境中子能谱及剂量率的多球谱仪测量[J]. 清华大学学报（自然科学版）, 2015, 55(12): 1332-1334,1341. HU Qingdong, ZENG Zhi, MA Hao, CHENG Jianping, LI Junli, ZHANG Hui, WANG Xin, WU Zhen. Measurement of indoor natural neutron spectrum with a Bonner sphere spectrometer. Journal of Tsinghua University(Science and Technology), 2015, 55(12): 1332-1334,1341. |
| 链接本文: |
| http://jst.tsinghuajournals.com/CN/10.16511/j.cnki.qhdxxb.2015.24.010或 http://jst.tsinghuajournals.com/CN/Y2015/V55/I12/1332 |
图表:
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| 图1 多球中子能谱仪MNSIL100 |
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| 图2 不同半径探测器的响应函数曲线 |
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| 表1 不同慢化球的1000s的平均计数 |
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| 图3 北京市室内中子能谱 |
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| 图4 室内中子周围剂量当量率的变化(2013年) |
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| 表2 多球谱仪计算值和剂量仪测量值 |
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