• M. Tawada, Y. Funakoshi, H. Koiso, N. Ohuchi, K. Oide, K. Tsuchiya
  KEK, Ibaraki

KEK is studying the design of the superconducting final focus quadrupoles for the Super KEKB. The system consists of quadrupole-doublet cooled at 1.9 K. The vertical focusing quadrupole has the maximum magnetic field more than 8 T in the superconducting coils. The field gradient at the magnet center is more than 80 T/m and the effective magnetic length is 0.25 m. The horizontal focusing quadrupole is designed with the field gradient of 9.5 T/m and the effective magnetic length of 1.0 m. These magnet parameters will be iterated in the process of optimizing the beam optics. In this paper, the conceptual design of final focusing system and magnets will be reported.

• B. Parker, M. Anerella, J. Escallier, P. He, A.K. Jain, A. Marone
  BNL, Upton, Long Island, New York
• B. Bolzon, A. Jeremie
  IN2P3-LAPP, Annecy-le-Vieux
• P.A. Coe, D. Urner
  OXFORDphysics, Oxford, Oxon
• C. Hauviller
  CERN, Geneva
• A. Seryi
  SLAC, Menlo Park, California
• T. Tauchi, K. Tsuchiya, J. Urakawa
  KEK, Ibaraki

Funding: Work supported by the U.S. Department of Energy under Contract No. DE-AC02-98CH10886.

The Accelerator Test Facility (ATF2) at KEK is a scaled down version of the final focus design proposed for the future linear colliders (LC) and aims to experimentally verify the final focus (FF) technology needed to obtain very small, stable beam spots at a LC interaction point. Initially the ATF2 FF is made using conventional (warm) quadrupole and sextupole magnets; however, we propose to upgrade the FF by replacing some of the conventional magnets with new superconducting magnets constructed with the same technology as those of the International Linear Collider baseline FF magnets*. With the superconducting magnet upgrade we can look to achieve smaller interaction point beta-functions and to study superconducting magnet vibration stability in an accelerator environment. Therefore for the ATF2 R&D magnet we endeavor to incorporate cryostat design features that facilitate monitoring of the cold mass movement via interferometric techniques. The design status of the ATF2 superconducting upgrade magnets is reported in this paper.

*International Linear Collider Reference Design Report, ILC-REPORT-2007-001, August 2007.

• 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.

• N. Ohuchi, H. Hayano, N. Higashi, H. Nakai, K. Tsuchiya, A. Yamamoto
  KEK, Ibaraki
• T.T. Arkan, H. Carter, M.S. Champion, J. Grimm, J.S. Kerby, D.V. Mitchell, T.J. Peterson, M.C. Ross
  Fermilab, Batavia
• S. Barbanotti, C. Pagani, P. Pierini
  INFN/LASA, Segrate (MI)
• L. Lilje
  DESY, Hamburg

In an attempt at demonstrating an average field gradient of 31.5 MV/m as per the design accelerating gradient for ILC, a program called S1-Global is in progress as an international research collaboration among KEK, INFN, FNAL, DESY and SLAC. The S1-Global cryomodule will contain eight superconducting cavities from FNAL, DESY and KEK. The cryomodule will be constructed by joining two half-size cryomodules, each 6 m in length. The module containing four cavities from FNAL and DESY will be constructed by INFN. The design of this module is based on an improved 3rd generation TTF design. KEK will modify the 6-meter STF cryomodule to contain four KEK cavities. The designs of the cryomodules are ongoing between these laboratories, and the operation of the system is scheduled at the KEK-STF from June 2010. In this paper, the S1-Global cryomodule plan and the module design will be presented. ‘S1-Global collaboration’ as a co-author.