Fujimoto, T.

Paper	Title	Page
THPLT062	Alternating-phase-focused Linac for an Injector of Medical Synchrotrons	2628
	Y. Iwata, T. Fujisawa, T. Furukawa, T. Kanai, M. Kanazawa, N. Kanematsu, M. Komori, S. Minohara, T. Murakami, M. Muramatsu, K. Noda, M. Torikoshi, S. Yamada NIRS, Chiba-shi Y.F. Fujii, T. Mitsumoto, H. Tsutsui SHI, Tokyo T. Fujimoto, H.O. Ogawa, S. Shibuya AEC, Chiba V. Kapin MEPhI, Moscow
	Tumor therapy using Heavy Ion Medical Accelerator in Chiba (HIMAC) has been made over ten years at National Institute of Radiological Sciences (NIRS). Due to the successful clinical results, the project on developing compact medical accelerators for the tumor therapy has been started. To design these compact facilities, the size of a linac as well as the construction and operation costs is important. To satisfy these requirements, we propose Alternating-Phase-Focused (APF) linac using an Interdigital H-mode cavity. Since the axial and radial focusing of beam is made just with the acceleration rf field, no additional focusing elements is needed for the APF linac. This feature would make the costs lower than those of conventional linacs. The practical design of the APF linac will be presented.
THPLT065	Study of Multiturn Injection at HIMAC Synchrotron	2637
	T.H. Uesugi, T. Furukawa, T. Naruse, K. Noda NIRS, Chiba-shi T. Fujimoto, S. Shibuya AEC, Chiba
	In the multiturn injection method at the HIMAC synchrotron, a collapsing speed of the bump orbit was decreased from 200 to 350 microseconds in order to obtain higher intensity beam. The injection line was readjusted to satisfy the optimum condition of multiturn injection method. Furthermore, COD correction and bump-orbit optimization were carried out. On the other hand, in order to prevent the resonance by tune shift and to keep the beam intensity constant, tune survey was carried out. While vertical tune is adjusted, we propose that the method to reduce beam loss after injection by expanding vertical beam size by means of the RF-knockout. This paper describes the improvement of injection at HIMAC synchrotron.
TUPLT087	Deflection Element for S-LSR	1357
	M. Ikegami, H. Fadil, A. Noda, T. Shirai, M. Tanabe, H. Tongu Kyoto ICR, Uji, Kyoto T. Fujimoto, K. Noda, H. Ogawa, S. Shibuya, T. Takeuchi NIRS, Chiba-shi M. Grieser MPI-K, Heidelberg H. Okamoto HU/AdSM, Higashi-Hiroshima
	Main lattice of the ion storage and cooler ring, S-LSR is composed of 6 dipole and 12 quadrupole magnets. The maximum magnetic field, the radius of curvature and gap height are 0.95 T, 1050 mm and 70 mm, respectively. The field measurement of the dipole magnets has been completed with use of Hall-probe position controlled by driving mechanism composed of stepping motors and ball-screws. In order to cancel out the momentum dispersion, the radial electric field is superposed with the magnetic field. The radial electric field is applied by the electrodes installed into the vacuum vessel set inside the rather limited gap of the dipole magnet. Good field quality is to be realized with use of intermediate electrodes. In the present paper, the results of the magnetic field measurements are presented together with the design of the superposed electric field.
WEPLT116	Lattice Design and Cooling Simulation at S-LSR	2119
	T. Shirai, H. Fadil, S. Fujimoto, M. Ikegami, A. Noda, M. Tanabe, H. Tongu Kyoto ICR, Uji, Kyoto T. Fujimoto, H. Fujiwara, K. Noda, S. Shibuya, T. Takeuchi NIRS, Chiba-shi M. Grieser MPI-K, Heidelberg H. Okamoto, Y. Yuri HU/AdSM, Higashi-Hiroshima E. Syresin JINR, Dubna, Moscow Region
	A compact ion cooler ring, S-LSR is under construction in Kyoto University. The circumference is 22.557 m and the maximum magnetic rigidity is 1 Tm. One of the important roles of S-LSR is a test bed to examine the lowest temperature limit of the ion beams using cooling techniques. The ultimate case is a crystalline one. The ring optics of S-LSR has a high super periodicity and a low phase advance to reduce the beam heating from the lattice structure. S-LSR has an electron beam cooling device and a laser cooling system for Mg. The simulation results show the possible limit of the ion beam temperature and the dependence on the operating betatron tunes.
THOBLH01	Recent Improvement of Slow-extraction at HIMAC Synchrotron	267
	T. Furukawa, T. Furukawa, T.H. Uesugi Chiba University, Graduate School of Science and Technology, Chiba T. Fujimoto, M. Kanazawa, K. Noda, S. Shibuya, E. Takada, S. Yamada NIRS, Chiba-shi T. Naruse Seikei University, Graduate School of Engineering, Tokyo
	At HIMAC synchrotron, two kinds of slow-extraction method have been developed and utilized: third-order resonant slow-extraction and that with RF-knockout, not only for ion therapy but also for physics and biological experiments. Thus, the improvements of the extracted beam quality have also been carried out in both methods. One of the improvements is the global spill control. The global spill is improved owing to analytical approach in both methods. Cooperating with the feedback system, the flat spill is easily obtained without gain control of the feedback during the extraction. On the other hand, the effect of longitudinal motion for the bunched beam was studied to suppress the frequency component of the synchrotron oscillation in the spill ripple. Further, the transport of the extracted beam is readjusted for controlling the beam size. In this paper, recent improvement of slow-extraction at HIMAC is presented.
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