| PHYSICS AND ENGINEERING PHYSICS |
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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 |
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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.
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| Keywords
Bonner sphere spectrometer
natural neutrons
spectrum
genetic algorithm
neutron dose
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Issue Date: 15 December 2015
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2015,
Vol. 55
