Completion of J-PARC mercury target system; Outline and topics

Haga, Katsuhiro  ; Kogawa, Hiroyuki  ; Wakui, Takashi  ; Hanano, Kohei; Futakawa, Masatoshi  

The construction of the mercury target system which is the 1MW class spallation neutron source under the J-PARC project has been completed. The mercury target system consists of the mercury target vessel, the mercury circulation system and the target trolley. The outline of the spallation neutron source in the material and life science experimental facility, and the mercury target system is reported. Several topics appeared in the course of the system fabrication and assembling are also reported. For the target vessel, the residual stress at the beam window was evaluated, and it was confirmed that the stress level is low and no problem. For the mercury pump, the outer shape and the structure of the mechanical PM pump which was newly developed and its operational results are reported. For the target trolley, the characteristic structure where all of the mercury related devices are mounted on the single trolley is reported.