• F. Noda
  Hitachi, Ltd., Energy and Environmental Systems laboratory, Hitachi-shi, Ibaraki-ken
• H. Akiyama
  Hitachi Ltd., Power & Industrial Systems, 1-1, Saiwai-cho, 3-chome
• F. Ebina, F. Fujitaka, H. Hae, H. Hiramoto, H. Nishiuchi, K. Saito, M. Umezawa
  Hitachi, Ltd., Energy and Environmental System Laboratory, Hitachi-shi

Slow cycle synchrotron system for cancer therapy is presented to realize the pencil beam scanning with carbon and proton. The designed synchrotron’s circumference is 60m and the maximum beam energies are 480MeV/u for carbon and 250MeV for proton. These energies correspond to the beam range of 35cm in water. In the treatment system with the present synchrotron, the discrete spot scanning scheme for lateral irradiation is employed using fast beam ON/OFF that is characteristic of the RF driven slow beam extraction from the synchrotron. Distal dose distribution is controlled with energy stacking technique, which is superimposing various bragg peaks which are controlled with the energy of the beam accelerated by the synchrotron. Furthermore, respiratory-gated operation with high throughput will be realized by the variable flat top length and timing for the beam extraction.

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

In J-PARC, Materials and Life Science 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, respectively, by 3-GeV proton beams. The first beam was achieved at the target without significant beam loss. To obtain the beam profile at the target, we applied an activation technique by using thin aluminum foil. In order to obtain reliable profile, it is required that a small number of shots for the beam adjustment and the beam stability. Since beam monitors works very well located at the beam transport line even in the first beam, the beam centralization can be finished by very small number of shots. The stability of beam for each pulse is recognized to be smaller than 1 mm. After many shots of irradiation, the 2-D beam profile can be obtained. It is found that the observed profile shows good agreement with the prediction calculation including the beam scattering at the proton beam window. The beam emittance is measured by the MWPM. It is found that the rms-beam emittance agree with the calculation by the SIMPSONS.