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TY - CPAPER AU - Walker, N. AU - Monaco, L. AU - Reschke, D. AU - Schaffran, J. AU - Steder, L. AU - Wiencek, M. TI - Update and Status of Vertical Test Results of the European XFEL Series Cavities J2 - Proc. of International Conference on RF Superconductivity (SRF2015), Whistler, BC, Canada, Sept. 13-18, 2015 AB - The series production by two industrial vendors of the 800 1.3-GHz superconducting cavities for the European XFEL has been on-going since the beginning of 2013 and will conclude towards the end of this year. As of publication some 740 cavities (~93%) have been produced at an average rate of 6 cavities per week. As part of the acceptance testing, all cavities have undergone at least one vertical RF test at 2K at the AMTF facility at DESY. The acceptance criterion for module assembly is based on the concept of a “usable gradient”, which is defined as the maximum field taking into account Q0 performance and allowed thresholds for field emission, as well as breakdown limits. Approximate 20% of the cavities have undergone further surface treatment in the DESY infrastructure to improve their usable gradient performance. In this paper we present the performance statistics of the vertical test results, as well as an analysis of the limiting criteria for the usable gradient, and finally the impact of the surface retreatment on both usable gradient and Q0. PB - JACoW CY - Geneva, Switzerland SP - 337 EP - 341 KW - cavity KW - status KW - linac KW - cryomodule KW - niobium DA - 2015/12 PY - 2015 SN - 978-3-95450-178-6 DO - 10.18429/JACoW-SRF2015-MOPB086 UR - http://srf2015.vrws.de/papers/mopb086.pdf ER -