• S.I. Meigo, M. Futakawa, M. Ohi, S. Shinichi
  JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
• H. Fujimori
  KEK/JAEA, Ibaraki-Ken

In J-PARC, Ma­te­ri­als and Life Sci­ence ex­per­i­men­tal Fa­cil­i­ty (MLF) is aimed at pro­mot­ing ex­per­i­ments using the world high­est in­ten­si­ty pulsed neu­tron and muon beams which are pro­duced at a thick mer­cury tar­get and a thin car­bon graphite tar­get by 3-GeV pro­ton beams, re­spec­tive­ly. The first beam was achieved at the tar­get with­out sig­nif­i­cant beam loss in May 2008. It is suc­ceed­ed sta­ble op­er­a­tion with beam power of larg­er than 300 kW. After beam ir­ra­di­a­tion, the resid­u­al dose of ra­di­a­tion on the beam trans­port line is re­mark­ably small where the high­est dose is 20 mi­croSv/h. In order to con­firm sta­ble op­er­a­tion of the fa­cil­i­ty, es­pe­cial­ly for the well­ness of the tar­get, it is im­por­tant to ob­tain the beam pro­file at the tar­get. We de­vel­oped new tech­nique by using imag­ing plate which is at­tached on the tar­get ves­sel by re­mote han­dling tech­nique via mas­ter slave ma­nip­u­la­tors. It is found that the beam pro­file shows good agree­ment with the cal­cu­la­tion. It is also found that the beam scat­ter­ing ef­fect on the muon pro­duc­tion tar­get shows good agree­ment with the sim­u­la­tion cal­cu­la­tion.