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arXiv · 2301.00959

System upgrade for $\mu$Bq/m$^3$ level $^{222}$Rn concentration measurement

Y. Liu·Y. P. Zhang·J. C. Liu·C. Guo·C. G. Yang. P. Zhang·Q. Tang·Z. F. Xu·C. Li·T. Y. Guan·S. B. Wang
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Abstract

The Jiangmen Underground Neutrino Observatory (JUNO), a 20 kton multipurpose underground liquid scintillator detector, was proposed for the determination of the neutrino mass hierarchy as primary physics goal. The central detector will be submerged in a water Cherenkov detector to lower the background from the environment and cosmic muons. Radon is one of the primary background sources. Nitrogen will be used in several sub-systems, and a highly sensitive radon detector has to be developed to measure its radon concentration. A system has been developed based on $^{222}$Rn enrichment of activated carbon and $^{222}$Rn detection based on the electrostatic collection. This paper presents the detail of a $\mu$Bq/m$^3$ level $^{222}$Rn concentration measurement system and gives detailed information about how the adsorption coefficient was measured and how the temperature, flow rate, and $^{222}$Rn concentration affect the adsorption coefficient.

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Y. Liu, Y. P. Zhang, J. C. Liu, C. Guo, C. G. Yang. P. Zhang, Q. Tang, Z. F. Xu, C. Li, T. Y. Guan, S. B. Wang. 2023-01-03. System upgrade for $\mu$Bq/m$^3$ level $^{222}$Rn concentration measurement. https://arxiv.org/abs/2301.00959

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