• T.W. Habermann, A. Balkcum, R. Begum, H.P. Bohlen, M. Cattelino, E. Cesca, L. Cox, E.L. Eisen, S. Forrest, D. Gajaria, T. Kimura, J.L. Ramirez-Aldana, A. Staprans, B. Stockwell, L. Zitelli
  CPI, Palo Alto, California

Funding: The authors would like to thank DESY for their support. In addition, we appreciate SLAC helping us out with test equipment.

CPI has designed and is currently in the process of building a prototype of a horizontally oriented multiple beam klystron (MBK) required to provide at least 10 MW peak rf output and 65% efficiency at 1300 MHz and 1.5% rf duty. The klystron was ordered by DESY for the European XFEL. In our design six off-axis electron beams go through seven ring resonators operating in the fundamental-mode. This ensures sufficient beam separation for longer cathode life while keeping the overall diameter of the device small. The MBK was designed using sate-of-the-art multi-dimensional design codes which showed that it was exceeding all performance requirements. First rf hot test data at reduced duty produced 11.2 MW peak saturated rf output and 74% efficiency, which was however accompanied by high beam interception. Initial optimization of the electromagnet resulted in a 70% reduction of the rf body current, but at the expense of rf output power, efficiency (down to 67%) and gain. The magnetic field balance has to be further optimized for low body current and high efficiency at all required operating conditions. Complete test data after optimization and tuning will be presented at the conference.

Slides

• P.A. McIntosh, R. Bate, C.D. Beard, D.M. Dykes, S.M. Pattalwar
  STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
• S.A. Belomestnykh, M. Liepe, H. Padamsee, J. Sears, V.D. Shemelin, V. Veshcherevich
  CLASSE, Ithaca, New York
• A. Büchner, F.G. Gabriel, P. Michel
  FZD, Dresden
• M.A. Cordwell, J. Strachan
  STFC/DL, Daresbury, Warrington, Cheshire
• J.N. Corlett, D. Li, S.M. Lidia
  LBNL, Berkeley, California
• T. Kimura, T.I. Smith
  Stanford University, Stanford, California
• D. Proch, J.K. Sekutowicz
  DESY, Hamburg
• A. Quigley
  STFC/DL/SRD, Daresbury, Warrington, Cheshire

The collaborative development of an optimised cavity/cryomodule solution for application on ERL facilities, has now progressed to final assembly and testing of the cavity string components and their subsequent cryomodule integration. This paper outlines the verification of the various cryomodule sub-components and details the processes utilised for final cavity string integration. The paper also describes the modifications needed to facilitate this new cryomodule installation and ultimate operation on the ALICE facility at Daresbury Laboratory.