Author: Fujinawa, T.
Paper Title Page
MOPFI025 Progress Towards High-Intensity Heavy-Ion Beams at RIKEN RIBF 333
  • O. Kamigaito, T. Dantsuka, M. Fujimaki, T. Fujinawa, N. Fukunishi, H. Hasebe, Y. Higurashi, E. Ikezawa, H. Imao, T. Kageyama, M. Kase, M. Kidera, M. Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, T. Nakagawa, M. Nakamura, J. Ohnishi, H. Okuno, K. Ozeki, N. Sakamoto, K. Suda, H. Watanabe, T. Watanabe, Y. Watanabe, K. Yamada, H. Yamasawa
    RIKEN Nishina Center, Wako, Japan
  The RIKEN RIBF(Radioactive Isotope Beam Factory) accelerator complex has been designed and constructed to provide heavy-ion beams from D to U ions with the energy of 400 MeV/u to the maximum. Though the goal intensity is 1 particle μ amperes for the whole mass range, the intensities of very heavy-ions from Ca to U are still not satisfactory. In 2012, owing to the intensity upgrade of 48Ca beams from ECR ion source, the beam current of 48Ca was 400 pnA which was improved by factors of 2 in comparison with that in 2011. Since 2011, the new injector RILAC2 has been successfully commissioned and operated very stably for beam service time, increasing the U beam intensity by an order of magnitude. Because it was no longer realistic to use carbon foil to strip the charge of intense U beams, in 2012 the Low-Z gas stripper system instead of the standard carbon foil system has been introduced and successfully worked. To accelerate the 238U64+ beams provided by the Low-Z gas stripper, modification of the following Fixed-frequency Ring Cyclotron was performed. In 2012, 15 pnA uranium beams which was four times larger than that provided in 2011 has been achieved.