Radionuclide monitoring stations in CTBT verification regime

Kumata, Masahiro; Oda, Tetsuzo; Miyamoto, Yutaka   ; Uchikoshi, Takako*; Nakahara, Yoshinori; Yamamoto, Yoichi ; Hokida, Takanori; Hirota, Naoki*; Inoue, Yoji; Shinohara, Nobuo 

The International Monitoring System (IMS) will be established across the world to verify compliance with the Comprehensive Test Ban Treaty (CTBT). The IMS will be capable of detecting and identifying nuclear explosions of detonated within the atmosphere, underwater and underground. 321 monitoring stations will be set around the world as a monitoring network of the IMS. The four technologies of seismology, hydroacoustic, infrasound, and radionuclide will be used for monitoring purposes. In order to build the radionuclide monitoring network, 80 radionuclide stations were chosen. Particles in the atmosphere are collected on a filter at each station to measure radioactivity by a HP-Ge detector. Further, 40 out of these 80 stations will be equipped with an automatic radioactive noble gas sampler/analyzer. The JAERI is establishing infrastructure to host radionuclide air monitoring equipment for two raionuclide stations in Japan. This paper presents the current status of the establishment and promising performance of the stations in Japan.