• 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.