Evaluation of residual tritium in stainless steel irradiated at SINQ target 3

Kikuchi, Kenji; Nakamura, Hirofumi; Tsujimoto, Kazufumi ; Kobayashi, Kazuhiro; Yokoyama, Sumi; Saito, Shigeru   ; Yamanishi, Toshihiko

A high-energy proton of 580MeV at SINQ target generates almost all constituents through spallation process with hydrogen and helium gases. For the SINQ target hydrogen and helium are generated to hundreds appm H and tens appm He, respectively. However, tritium gas production has not been yet reported. Evaluation of tritium gas generation in the specimens of target 3 was done by calculation. Results were compared with gamma spectrum measurement. Residual tritium measurement was carried by the thermal desorption method. It is found that a release of tritium began over 250C and material included 4 MBq/g. The ratio of residual tritium to generated one is estimated to be less than 20%.