Author: Natsui, T.
Paper Title Page
MOPLB02 Positron Injector Linac Upgrade for SuperKEKB 141
 
  • T. Kamitani, M. Akemoto, D.A. Arakawa, Y. Arakida, A. Enomoto, S. Fukuda, K. Furukawa, Y. Higashi, T. Higo, H. Honma, N. Iida, M. Ikeda, E. Kadokura, K. Kakihara, H. Katagiri, M. Kurashina, S. Matsumoto, T. Matsumoto, H. Matsushita, S. Michizono, K. Mikawa, T. Miura, F. Miyahara, T. Mori, H. Nakajima, K. Nakao, T. Natsui, Y. Ogawa, S. Ohsawa, M. Satoh, T. Shidara, A. Shirakawa, H. Sugimoto, T. Suwada, T. Takatomi, T. Takenaka, Y. Yano, K. Yokoyama, M. Yoshida, L. Zang, X. Zhou
    KEK, Ibaraki, Japan
  • D. Satoh
    TIT, Tokyo, Japan
 
  The KEKB B-factory is under an upgrade construction for the SuperKEKB. To achieve 40 times higher luminosity, the linac is required to inject electrons and positrons with higher intensities (e-: 1 nC → 5 nC, e+: 1 nC → 4 nC) and lower emittances (e-: 300 → 20 μm, e+: 2100 → 10 μm). This paper describes the upgrade scheme of the positron source. A new positron capture section will have larger transverse and energy acceptances by introducing a flux concentrator and large aperture L-band and S-band accelerating structures. Beam line layout and quadrupole focusing system will be rearranged for the enlarged beam acceptance. Beam optics is designed to be compatible for positron and electron beams with different energies and emittances. Pulsed quadrupoles and steering magnets are added for better flexibility in optics and orbit tuning. Parameter optimization of the positron source by optics calculation and particle tracking simulation is described.  
slides icon Slides MOPLB02 [0.575 MB]  
 
MOPB002 Positron Injector Linac Upgrade for SuperKEKB 177
 
  • T. Kamitani, M. Akemoto, D.A. Arakawa, Y. Arakida, A. Enomoto, S. Fukuda, K. Furukawa, Y. Higashi, T. Higo, H. Honma, N. Iida, M. Ikeda, E. Kadokura, K. Kakihara, H. Katagiri, M. Kurashina, S. Matsumoto, T. Matsumoto, H. Matsushita, S. Michizono, K. Mikawa, T. Miura, F. Miyahara, T. Mori, K. Nakao, T. Natsui, Y. Ogawa, S. Ohsawa, T. Shidara, A. Shirakawa, H. Sugimoto, T. Suwada, T. Takatomi, T. Takenaka, Y. Yano, K. Yokoyama, M. Yoshida, L. Zang, X. Zhou
    KEK, Ibaraki, Japan
  • D. Satoh
    TIT, Tokyo, Japan
 
  The KEKB B-factory is under an upgrade construction for the SuperKEKB. To achieve 40 times higher luminosity, the linac is required to inject electrons and positrons with higher intensities (e-: 1 nC → 5 nC, e+: 1 nC → 4 nC) and lower emittances (e-: 300 → 20 μm, e+: 2100 → 10 μm). This paper describes the upgrade scheme of the positron source. A new positron capture section will have larger transverse and energy acceptances by introducing a flux concentrator and large aperture L-band and S-band accelerating structures. Beam line layout and quadrupole focusing system will be rearranged for the enlarged beam acceptance. Beam optics is designed to be compatible for positron and electron beams with different energies and emittances. Pulsed quadrupoles and steering magnets are added for better flexibility in optics and orbit tuning. Parameter optimization of the positron source by optics calculation and particle tracking simulation is described.  
 
THPB095 Designing of a Phase-mask-type Laser Driven Dielectric Accelerator for Radiobiology 1041
 
  • K. Koyama
    UTNL, Ibaraki, Japan
  • A. Aimidura, M. Uesaka
    The University of Tokyo, Nuclear Professional School, Ibaraki-ken, Japan
  • Y. Matsumura
    University of Tokyo, Tokyo, Japan
  • T. Natsui, M. Yoshida
    KEK, Ibaraki, Japan
 
  Funding: This work is supported by KAKENHI, Grant-in-Aid for Scientific Research (C) 24510120
In order to estimate the health risk of a low radiation dose, basic processes of the radiobiology should be clarified by shooting a DNA using a spatially and temporary defined particle beam or X-ray. A suitable beam size is as small as a resolving power of an optical microscope of a few hundred nanometers. Photonic crystal accelerators (PCA) are capable of delivering nm-beams of sub-fs pulses because the characteristic length and frequency of PCAs are on the order of the laser light. Since the phase-mask type accelerator has a simpler structure than other types of PCAs, we are designing a phase-mask type laser driven dielectric accelerator. By adopting an unbalanced length of pillar and ditch (grating) of 4:1, a standing wave like acceleration field is produced in a acceleration channel. A pillar height and initial speed of injected electron are determined by analytically. The maximum acceleration gradient of 2 GeV/m is estimated. The required laser power is roughly estimated to be 6.5 GW. The simulation using CST-code also shows similar values to accelerate electrons by the phase-mask type accelerator.