作者：姚顺和, 刁立军, 朱保吉, 杨巧玲, 姚艳玲, 邢雨, 吕晓侠, 陈克胜
作者单位：中国原子能科学研究院计量与校准技术重点实验室, 北京 102413
关键词：氡;低本底;α电离室;γ谱仪
摘要：
利用大面积低本底α电离室和反宇宙射线低本底γ谱仪对低本底测量中氡的影响和去除进行研究。大面积低本底α电离室采用流气模式充入高纯氮气去除探测器中的氡，可以将本底计数率从0.83/s降低到0.037/s，消除氡的影响。反宇宙射线低本底γ谱仪将高纯锗探测器液氮罐挥发出来的氮气充入屏蔽室中去除氡，可以将本底的计数率从0.31/s降低到0.11/s，并消除氡子体的干扰峰。该研究证实在低本底测量中氡的影响是显著的且对氡的去除是必要的。
The influence and elimination of radon in low background measurement
YAO Shunhe, DIAO Lijun, ZHU Baoji, YANG Qiaoling, YAO Yanling, XING Yu, LÜ Xiaoxia, CHEN Kesheng
National Key Laboratory for Metrology and Calibration Techniques, China Institute of Atomic Energy, Beijing 102413,China
Abstract: The paper presents the influence and elimination of radon in low background measurements through the low background alpha ionization chamber and the anti-cosmic low-background γ-ray spectrometer at CIAE. The low background alpha ionization chamber is operated in flow mode and purged with high purity nitrogen gas to eliminate the influence of radon, resulting in the background rate decreasing from 0.83/s to 0.037/s. The shielding room of the anti-cosmic low-background γ-ray spectrometer is purged with the boil-off nitrogen gas from the liquid nitrogen Dewar. Consequently, the background rate decreases from 0.31/s to 0.11/s and the energy peaks from radon daughter products are removed. It is clear that the influence of radon is obvious and the elimination of radon is necessary in low background measurements.
Keywords: radon;low background;alpha ionization chamber;γ-ray spectrometer
2020, 46(4):70-72,96 收稿日期: 2019-04-30;收到修改稿日期: 2019-07-16
基金项目:
作者简介: 姚顺和(1981-),男,甘肃镇原县人,副研究员,博士,主要研究方向为放射性计量与测量
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