Neutron background measurements at China Jinping underground laboratory with a Bonner Multi-sphere Spectrometer

Qingdong Hu; Hao Ma; Zhi Zeng; Jianping Cheng; Yunhua Chen; Shenming He; Junli Li; Manbin Shen; Shiyong Wu; Qian Yue; Jianfeng Yue; Hui Zhang

doi:10.1016/j.nima.2017.03.048

arXiv · 1612.04054

Neutron background measurements at China Jinping underground laboratory with a Bonner Multi-sphere Spectrometer

Qingdong Hu·Hao Ma·Zhi Zeng·Jianping Cheng·Yunhua Chen·Shenming He·Junli Li·Manbin Shen·Shiyong Wu·Qian Yue·Jianfeng Yue·Hui Zhang

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Abstract

The neutron background spectrum from thermal neutron to 20 MeV fast neutron was measured at the first experimental hall of China Jinping underground laboratory with a Bonner multi-sphere spectrometer. The measurement system was validated by a Cf252 source and inconformity was corrected. Due to micro charge discharge, the dataset was screened and background from the steel of the detectors was estimated by MC simulation. Based on genetic algorithm we obtained the energy distribution of the neutron and the total flux of neutron was (2.69 +/-1.02) *10^-5 cm^-2s^-1

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Qingdong Hu, Hao Ma, Zhi Zeng, Jianping Cheng, Yunhua Chen, Shenming He, Junli Li, Manbin Shen, Shiyong Wu, Qian Yue, Jianfeng Yue, Hui Zhang. 2016-12-13. Neutron background measurements at China Jinping underground laboratory with a Bonner Multi-sphere Spectrometer. https://doi.org/10.1016/j.nima.2017.03.048

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