ATM analysis results on radioxenons detected in Japan by JAEA/NDC

Kijima, Yuichi ; Yamamoto, Yoichi ; Tomita, Yutaka 

Using the contribution from the Japanese government to the CTBTO for the purpose of strengthening of the CTBTO's detection capability for nuclear tests, the JAEA installed the Transportable Xenon Laboratories (TXLs) in collaboration with the CTBTO at Horonobe, Hokkaido and Mutsu, Aomori, and has been measuring radioxenon since 2018. Therefore, the measurements of radioxenon in Japan for monitoring nuclear tests are currently conducted at total 3 measuring points (Horonobe TXL, Mutsu TXL and Takasaki IMS station). In the past measurement results, the radioxenon isotopes with activity concentration above the background level were detected at these measuring points. The JAEA/NDC carried out the ATM analyses for the investigation of an emission source of the radioxenon isotopes for some detection cases. We report the measurement results of radioxenon and the ATM analysis results.