Process of off-gas generated from the spallation neutron source (JSNS) in J-PARC

Kasugai, Yoshimi  ; Kai, Tetsuya   ; Otsu, Kiichi; Futakawa, Masatoshi  ; Ikeda, Yujiro

Various kinds of the spallation products are generated in the mercury used as the spallation neutron source (JSNS) at the Materials and Life Science Facility in J-PARC. In particular, gas products are accumulated in the gas phase of the mercury tank in the mercury circulation system. An off-gas processing system has been installed in order to process the off-gas and enable the gas release to the environment under the concentration limit of radioactivity. In this presentation, we report the calculation of the amount of the radioactive gas product in the mercury, which is used for the system design as a basis, outline of the off-gas process and the activity measurement of the off-gas after the commissioning of JSNS with low power operation.