Author: Kumaki, M.
Paper Title Page
MOPRI010 Laser Ablation Ion Source for the KEK Digital Accelerator 598
 
  • N. Munemoto
    Department of Energy Sciences, Tokyo Institute of Technology, Yokohama, Japan
  • Y. Fuwa, S. Ikeda, M. Kumaki
    RIKEN, Saitama, Japan
  • Y. Fuwa
    Kyoto ICR, Uji, Kyoto, Japan
  • S. Ikeda, K. Takayama
    TIT, Yokohama, Japan
  • M. Kumaki
    RISE, Tokyo, Japan
  • M. Okamura
    BNL, Upton, Long Island, New York, USA
  • S. Takano, K. Takayama
    KEK, Ibaraki, Japan
  • K. Takayama
    Sokendai, Ibaraki, Japan
 
  KEK Digital Accelerator (DA) is a small scale induction synchrotron and operated at 10Hz and recently has succeeded to accelerate gaseous ions*. There is a strong demand of fully striped carbon ions because the DA is regarded as the second generation of cancer therapy driver, which does not require an injector and electron stripper. We need a novel carbon ion source providing C6+ beams, which are directly injected into the DA and accelerated up to required energy. For this purpose, a laser ablation ion source(LAIS) is promising**. To obtain high yield C6+ ions from ablation plasma, the laser irradiation condition has been evaluated and relationship between beam properties of charge spectrum, intensity, and temperature, and carbon target materials were examined. Two laser systems, long pulse (6 ns) and short pulse (170 ps), were employed to irradiate a graphite and amorphous carbon target. The current densities and profile of the generated plasmas in time were measured and charge state distributions were analyzed. In addition we will report a full design integrating this LAIS, the extraction system, the longitudinal chopper system, and the low energy beam transport line.
* T.Yoshimoto et al., presented in this conference
** N.Munemoto et al., Proceedings of ICIS2013, published in Rev. Sci. Inst.
 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI010  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPRI011 Control of Plasma Flux with Pulsed Solenoid for Laser Ion Source 601
SUSPSNE027   use link to see paper's listing under its alternate paper code  
 
  • S. Ikeda, K. Horioka
    TIT, Yokohama, Japan
  • Y. Fuwa, S. Ikeda, M. Kumaki
    RIKEN, Saitama, Japan
  • T. Kanesue, M. Okamura
    BNL, Upton, Long Island, New York, USA
 
  We discuss the behavior of laser-ablation plasma spreading through a pulsed solenoidal field to minimize the beam emittance of laser-ablation ion source (LIS). LIS is expected to produce high-flux and low emittance ion beams from various solid materials in vacuum because of the high drift velocity and low temperature of the ablation plasma due to the adiabatic expansion. However, the ion flux level from the ablation plasma into an extraction gap changes within a pulse and then the shape of the sheath boundary changes transiently. Then, the integrated emittance is larger than the stroboscopic emittance at a certain time slice. To prevent the transient effect, we tried to control the plasma flux with a pulsed solenoidal magnetic field. The field is expected to change the direction of the plasma flow like a lens. By changing the magnetic flux density according to the transient flux level of ablation plasma, we can expect to control the plasma flux at the extraction gap. To investigate the controllability of the plasma flow, we measured the plasma flux as a function of parameters of the pulsed magnetic field. We scanned ion probes along the beam.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-MOPRI011  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)