A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

Hattori, T.

Paper Title Page
THPP022 IH Linac with Higher-order Modes 3419
 
  • N. Hayashizaki, T. Hattori
    RLNR, Tokyo
 
  As one of a drift tube type linac, an Interdigital H-type (IH) linac has been applied for ion acceleration in low beta range. It can realize a resonant cavity of convenient size at low frequency band and higher shunt impedance at low velocity range. These characteristics are advantageous especially for heavy ion acceleration; therefore, this structure has been applied for heavy ion cancer therapy. The RF field is resonated in TE111 mode and the electric field does not have the axial field component. The accelerating field is excited by using the electrode of Interdigital shape. In order to apply this structure to intermediate beta range, we propose a IH linac with the TE11n mode of the higher-order mode (HOM). Although the operating frequency becomes higher by using HOM, it is convenient to accelerate ion beam of intermediate energy. The design of the cavity structure and the possibility are presented.  
THPP107 Lifetime Comparisons of Single and Double Layered HBC-Foils using 3.2MeV Ne+ Ion Beam 3617
 
  • I. Sugai, Y. Irie, H. Kawakami, M. Oyaizu, A. Takagi, Y. Takeda
    KEK, Ibaraki
  • T. Hattori, K. K. Kawasaki
    RLNR, Tokyo
 
  The Japan-Proton Accelerator Research Complex (J-PARC) requires thick carbon stripper foils of 300-500 μg/cm2 thick to strip electrons from the H-beam supplied by the linac before injection into the RCS. The energy depositions upon foil by the intense circulating proton bunched beam as well as H-beam result in the foil temperature of ~1800K. Thus, conventional carbon stripper foils will rupture in a very short time and even a high quality diamond foil will be broken at around 1800 K. Therfore, thick carbon stripper foils with high durability even at 1800K are indispensable for such accelerators. We have developed HBC (Hybrid type Boron mixed Carbon)-foil. We have measured the lifetime of a double and single-layered HBC-foils, diamond (DM) foils and commercially available carbon (CM) foils for comparisons using 3.2 MeV Ne+ ion beam, in which a significant amount of energy loss is deposited in the foils. The lifetime of the double-layered HBC- foil (180 μg/cm2 x 2) was found to be long 18 and 446 times longer than those of DM-foil (360μg/cm2 x 1) and double-layered CM foils ( 207μg/cm2 x 2), respectively.