• N. Ohuchi, M. Akemoto, S. Fukuda, H. Hayano, N. Higashi, E. Kako, H. Katagiri, Y. Kojima, Y. Kondou, T. Matsumoto, H. Matsushita, S. Michizono, T. Miura, H. Nakai, H. Nakajima, S. Noguchi, M. Satoh, T. Shidara, T. Shishido, T. Takenaka, A. Terashima, N. Toge, K. Tsuchiya, K. Watanabe, S. Yamaguchi, A. Yamamoto, Y. Yamamoto, K. Yokoya, M. Yoshida
  KEK, Ibaraki
• C. Adolphsen, C.D. Nantista
  SLAC, Menlo Park, California
• T.T. Arkan, S. Barbanotti, H. Carter, M.S. Champion, R.D. Kephart, J.S. Kerby, D.V. Mitchell, Y. Orlov, T.J. Peterson, M.C. Ross
  Fermilab, Batavia
• A. Bosotti, C. Pagani, R. Paparella, P. Pierini
  INFN/LASA, Segrate (MI)
• D. Kostin, L. Lilje, A. Matheisen, W.-D. Möller, N.J. Walker, H. Weise
  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 design of the S1-G cryomodule began at May 2008 by INFN and KEK. The S1-Global cryomodule was designed to contain eight superconducting cavities from FNAL, DESY and KEK, and to be constructed by joining two half-size cryomodules, each 6 m in length. The module containing four cavities from FNAL and DESY was constructed by INFN. Four KEK cavities have been assembled in the 6 m module which KEK fabricated. All major components were transported to KEK from INFN, FNAL and DESY in December 2009. The assembly of the two 6-m cryomodules started from January 2010 in a collaborative work of FNAL, DESY, INFN and KEK. The construction of the S1-G cryomodule will complete in May, and the cool-down of the S1-G cryomodule is scheduled from June 2010 at the KEK-STF. In this paper, the construction and the cold tests of the S1-Global cryomodule in the worldwide research collaboration will be presented.

Slides

• J. Iversen, R. Bandelmann, G. Kreps, W.-D. Möller, D. Proch, J.K. Sekutowicz, W. Singer
  DESY, Hamburg

Since 1993 DESY ordered 165 1.3GHz 9-cell superconducting cavities. The cavities have been developed for TeV-Energy Superconducting Linear Accelerator (TESLA) and are used in the linac of the Free Electron Laser in Hamburg (FLASH). The fabrication of all cavities was done in 9 production groups at industry. From the beginning the industrialization was carried out in close collaboration between DESY and the industry. From order to order the cavity design was optimized and the fabrication sequences were improved to realize stable and better cavity performance and to safe costs. Now a final cavity design for the European XFEL is defined. We summarize the development phases and design changes up to the final XFEL design. An outlook on the near future production of hundreds of cavities for XFEL based on our experience will be given.