• N. Fukunishi, T. Dantsuka, M. Fujimaki, A. Goto, H. Hasebe, Y. Higurashi, E. Ikezawa, T. Kageyama, O. Kamigaito, M. Kase, M. Kidera, M. Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, T. Nakagawa, J. Ohnishi, H. Okuno, N. Sakamoto, Y. Sato, K. Sekiguchi, K. Suda, H. Suzuki, M. Wakasugi, H. Watanabe, T. Watanabe, Y. Watanabe, K. Yamada, Y. Yano, S. Yokouchi
  RIKEN Nishina Center, Wako

The RIKEN RI Beam Factory (RIBF) is pushing the limits of energy for heavy ion cyclotrons. The first experiment of the RIBF has successfully finished with the discovery of new isotopes ¹²⁵Pd and ¹²⁶Pd* in June 2007 with a 345-MeV/nucleon uranium beam. However, the total transmission efficiency was limited to be less than 1%. In addition, a carry-over of oil was found in the refrigerator of the Superconducting Ring Cyclotron (SRC), which was the main accelerator of the RIBF. To solve these problems, we have improved beam monitors, upgraded the oil remover system of the compressor of the liquid helium cryogenic plant at SRC and made a series of acceleration tests. As a result, 0.3 pnA of a 345-MeV/nucleon uranium beam was stably delivered to RIBF users in November 2008 and a 345-MeV/nucleon ⁴⁸Ca beam with the intensity of 170 pnA was obtained in December 2008. In the PAC09 presentation, we will summarize our operating experience with the SRC and developments of RIBF accelerators in addition to most up-to-date performance of the RIBF accelerator complex.

*T. Ohnishi et al., J. Phys. Soc. Jpn. 77 (2008) 083201

Slides

• T. Nakagawa
  RIKEN Nishina Center, Wako

Significant progress has been achieved since first ECR ion source was developed more than three decades ago and it became one of the best ion sources for heavy ion accelerators in the world. Such progress has been mainly due to utilization of higher microwave frequency and stronger magnetic confinement, technical innovations, and understanding of the production mechanisms of highly charged heavy ions in ECR plasma. Especially, in the last decade, the progress is strongly dependent on advances in the superconducting magnet technology and understanding of the Physics of ECR plasma. Very recently, as the interest in the radioactive beam for research in various fields grows, the need for more intense beam of highly charged heavy ions to inject into the accelerator requires new innovation to improve the ECR ion source performance. In this contribution, I will present the progress of the technology and physics of ECR ion sources. Based on these results, the concepts for next generation ECR ion source for meet the requirements will be presented.

Slides