Update of DPA and nuclear heat calculations in spallation neutron source at J-PARC

Harada, Masahide   ; Takada, Hiroshi   

In the spallation neutron source at J-PARC, proton beam hits a mercury target. Above or below the target, there are three liquid hydrogen moderators. Around the target and moderator, beryllium and iron reflectors are located. These components with helium atmosphere are set into the vessel which has a proton-beam windows. In the design stage, for a construction of maintenance and storage scenarios, DPA which is a major index of radiation damage were evaluated for each component with the PHITS code. And for mechanical designs of the target, the moderator and so on, nuclear heat was also estimated with the PHITS code. The PHITS code was recently updated recently. Therefore, the DPA calculation and the nuclear heat calculation were updated with the latest PHITS code. As results, it was confirmed that there was little significant difference between the latest estimated data and the old ones.