• T. Mimashi, K. Furukawa, N. Iida, K. Kakihara, M. Kikuchi, T. Miyajima, S. Nagahashi, M. Sato, M. Tawada, A. Ueda
  KEK, Ibaraki
• N. Ishii
  Tigold, Chiba 289-1226
• K. Iwamoto
  KFG, NEUSS
• S. Kodama, A. Sasagawa
  KYOCERA Corporation, Higashiomi-city, Shiga
• T. Kudo
  MELCO SC, Tsukuba
• H. Mori
  Nichicon (Kusatsu) Corporation, Shiga

The KEK Linac delivers the beam to KEK-Photon factory storage ring, KEKB ring and the advanced ring for photon factory. In order to deliver the beam to the KEK-photon factory and KEKB ring simultaneously, the pulsed bending magnet was installed at the end of KEKB Linac. The pulsed bending magnet extract 2.5GeV electron beam to the PF beam transfer line. The deflection angle of the magnet is 0.114 radians and the field strength is almost 1.22T. The peak current stability is better than 0.1% at 24kA operation. The maximum repetition rate is 25Hz. The 1.2m long ceramic chamber is inserted into the 1m long magnet. This system makes possible the top up operation of PF ring.

• M. Tawada, M. Kikuchi, T. Mimashi, S. Nagahashi, A. Ueda
  KEK, Ibaraki

KEKB linac is a 600 m long electron linac and is used to deliver beam to four rings, KEKB HER ring (electron, 8 GeV), KEKB LER ring (positron, 3.5 GeV),PF ring (electron, 2.5 GeV) and PF-AR ring (electron, 6.5 GeV). KEKB rings are operated under top-up injection mode and have occupied the current linac operation mostly. Simultaneous injection to three rings (KEKB HER and KEKB LER and PF) is required due to the top-up injection to PF ring is required recently. We have developed the pulsed bending magnet for this. This magnet produces 114 mrad deflection angle for 2.5 GeV PF beam. The fast switching between KEKB and PF can be performed up to 25 Hz. We will describe this magnet system in detail.

• N. Iida, K. Furukawa, M. Ikeda, T. Kamitani, M. Kikuchi, E. Kikutani, Y. Kobayashi, T. Mimashi, T.M. Mitsuhashi, T. Miura, Y. Ogawa, Y. Ohnishi, S. Ohsawa, M. Satoh, M. Suetake, T. Suwada, M. Tawada, A. Ueda, Y. Yano, K. Yokoyama, M. Yoshida
  KEK, Ibaraki

The e+/e^- injector LINAC in KEK usually successively injects into four rings, which are Low Energy Ring (LER) of KEKB (3.5GeV/e+), High Energy Ring (HER) of KEKB (8.0GeV/e-), Photon Factory (PF) (2.5GeV/e-) and Advanced Ring for pulse X-rays (PF-AR) (3.0GeV/e-). While LINAC continuously injects into LER and HER alternatively every about five minutes, keeping both of KEKB rings almost their full operating currents. It takes about one minute to switch beam mode of LINAC. PF and PF-AR are injected a few times in a day. Time for PF or PF-AR including mode-switch had taken about 20 minutes for each other. For PF injection, the switching time was shortened in 2005 and the occupancy time is about 5 minutes. In 2008, we succeeded to make the switching time shorter, 2 seconds for HER/LER, and Pulse-to-pulse alternatively injection for PF/HER using an event system. Especially for KEKB, the short switching time is contributed to provide high currents and to improve luminosity at which beam lives are too short to keep the high currents. In 2009, we have a plan to inject also for LER/HER pulse-to-pulse alternatively.

• Y. Kobayashi, T. Aoto, S. Asaoka, K. Ebihara, K. Haga, K. Harada, T. Honda, T. Ieiri, M. Izawa, T. Kageyama, T. Kasuga, M. Kikuchi, K. Kudo, H. Maezawa, K. Marutsuka, A. Mishina, T.M. Mitsuhashi, T. Miyajima, H. Miyauchi, S. Nagahashi, T.T. Nakamura, T. Nogami, T. Obina, K. Oide, M. Ono, T. Ozaki, C.O. Pak, H. Sakai, Y. Sakamoto, S. Sakanaka, H. Sasaki, Y. Sato, M. Shimada, T. Shioya, M. Tadano, T. Tahara, T. Takahashi, R. Takai, S. Takasaki, Y. Tanimoto, M. Tejima, K. Tsuchiya, T. Uchiyama, A. Ueda, K. Umemori, S. Yamamoto, Ma. Yoshida, S.I. Yoshimoto
  KEK, Ibaraki

Two synchrotron light sources of the Photon Factory storage ring (PF-ring) and the Photon Factory advanced ring (PF-AR) have been stably operated at KEK. PF-ring covers the photon-energy range from VUV to hard X-ray using a 2.5 GeV (sometimes 3.0 GeV) electron beam. PF-AR is mostly operated in a single-bunch mode of 6.5GeV to provide pulsed hard X-rays. Recently, the operation has progressed to realize a so-called top-up injection at PF-ring. In a single-bunch mode, the continuous injection to preserve a constant beam current of 51 mA has been carried out since February 2007. In addition, the injection with continuing the experiments has been successfully operated in a multi-bunch mode since October 2008. At PF-AR, sputter ion pumps have been extensively reinforced to prolong the beam lifetime and to reduce the frequency of sudden lifetime drops by substituting for distributed ion pumps, which are considered as one of the dust sources. In this conference, we present the recent progress of the operation at PF-ring and PF-AR including machine developments.

• S. Sakanaka, M. Akemoto, T. Aoto, D.A. Arakawa, A. Enomoto, S. Fukuda, K. Furukawa, T. Furuya, K. Haga, K. Hara, K. Harada, T. Honda, Y. Honda, H. Honma, T. Honma, K. Hosoyama, M. Isawa, E. Kako, T. Kasuga, H. Kawata, M. Kikuchi, Y. Kobayashi, Y. Kojima, T. Matsumoto, H. Matsushita, S. Michizono, T.M. Mitsuhashi, T. Miura, T. Miyajima, T. Muto, S. Nagahashi, T. Naito, H. Nakai, H. Nakajima, E. Nakamura, K. Nakanishi, T. Nogami, S. Noguchi, T. Obina, S. Ohsawa, T. Ozaki, S. Sasaki, K. Satoh, M. Satoh, T. Shidara, M. Shimada, T. Shioya, T. Shishido, T. Suwada, T. Takahashi, R. Takai, Y. Tanimoto, M. Tawada, M. Tobiyama, K. Tsuchiya, T. Uchiyama, K. Umemori, K. Watanabe, M. Yamamoto, S. Yamamoto, Y. Yamamoto
  KEK, Ibaraki
• R. Hajima, H. Iijima, N. Kikuzawa, E.J. Minehara, R. Nagai, N. Nishimori, M. Sawamura
  JAEA/ERL, Ibaraki
• H. Hanaki
  JASRI/SPring-8, Hyogo-ken
• A. Ishii, I. Ito, T. Kawasaki, H. Kudo, N. Nakamura, H. Sakai, S. Shibuya, K. Shinoe, T. Shiraga, H. Takaki
  ISSP/SRL, Chiba
• M. Katoh
  UVSOR, Okazaki
• M. Kuriki
  HU/AdSM, Higashi-Hiroshima
• S. Matsuba
  Hiroshima University, Graduate School of Science, Higashi-Hiroshima
• K. Torizuka, D. Yoshitomi
  AIST, Tsukuba

Future synchrotron light source project using an energy recovery linac (ERL) is under proposal at the High Energy Accelerator Research Organization (KEK) in collaboration with several Japanese institutes such as the JAEA and the ISSP. We are on the way to develop such key technologies as the super-brilliant DC photo-injector and superconducting cavities that are suitable for both CW and high-current operations. We are also promoting the construction of the Compact ERL for demonstrating such key technologies. We report the latest status of our project, including update results from our photo-injector and from both superconducting cavities for the injector and the main linac, as well as the progress in the design and preparations for constructing the Compact ERL.

• Y. Funakoshi, T. Abe, K. Akai, Y. Cai, K. Ebihara, K. Egawa, A. Enomoto, J.W. Flanagan, H. Fukuma, K. Furukawa, T. Furuya, J. Haba, T. Ieiri, N. Iida, H. Ikeda, T. Kageyama, S. Kamada, T. Kamitani, S. Kato, M. Kikuchi, E. Kikutani, H. Koiso, M. Masuzawa, T. Mimashi, T. Miura, A. Morita, T.T. Nakamura, K. Nakanishi, M. Nishiwaki, Y. Ogawa, K. Ohmi, Y. Ohnishi, N. Ohuchi, K. Oide, M. Ono, Y. Seimiya, K. Shibata, M. Suetake, Y. Suetsugu, T. Sugimura, T. Suwada, M. Tawada, M. Tejima, M. Tobiyama, N. Tokuda, S. Uehara, S. Uno, Y. Yamamoto, Y. Yano, K. Yokoyama, M. Yoshida, S.I. Yoshimoto, D.M. Zhou
  KEK, Ibaraki

Crab cavities were installed at KEKB at the beginning of 2007. The beam operation with the crab cavities is in progress. In this paper, machine performance with crab crossing is described focusing on a specific luminosity and a beam lifetime issue related to the dynamic beam-beam effects.