Author: Cichalewski, W.
Paper Title Page
TUPB019 Second CW and LP Operation Test of XFEL Prototype Cryomodule 516
  • J.K. Sekutowicz, V. Ayvazyan, J. Branlard, M. Ebert, J. Eschke, A. Gössel, D. Kostin, W. Merz, F. Mittag, R. Onken
    DESY, Hamburg, Germany
  • W. Cichalewski, W. Jałmużna, A. Piotrowski, K.P. Przygoda
    TUL-DMCS, Łódź, Poland
  • K. Czuba, Ł. Zembala
    Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
  • I.M. Kudla, J. Szewiński
    NCBJ, Świerk/Otwock, Poland
  In summer 2011, we have performed the first test of continuous wave (cw) and long pulse (lp) operation of the XFEL prototype cryomodule, which originally has been designed for short pulse operation. In April and June 2012, the second test took place, with the next cryomodule prototype. For that test cooling in the cryomodule was improved and new LLRF system has been implemented. In this contribution we discuss results of the second RF test of these new types of operation, which can in the future extend flexibility in the time beam structure of the European XFEL facility  
THPB085 LLRF Automation for the 9mA ILC Tests at FLASH 1023
  • J. Branlard, V. Ayvazyan, O. Hensler, H. Schlarb, Ch. Schmidt, N.J. Walker, M. Walla
    DESY, Hamburg, Germany
  • G.I. Cancelo, B. Chase
    Fermilab, Batavia, USA
  • J. Carwardine
    ANL, Argonne, USA
  • W. Cichalewski, W. Jałmużna
    TUL-DMCS, Łódź, Poland
  • S. Michizono
    KEK, Ibaraki, Japan
  Since 2009 and under the scope of the International Linear Collider (ILC) R&D, a series of studies takes place twice a year at the Free electron Laser accelerator in Hamburg, (FLASH) DESY, in order to investigate technical challenges related to the high-gradient, high-beam-current design of the ILC. Such issues as operating cavities near their quench limit with high beam loading or in klystron saturation regime are investigated, always pushing the limits of FLASH nominal operational conditions. To support these studies, a series of automation algorithms have been developed and implemented at DESY. These include automatic detection of cavity quenches, automatic adjustment of the superconducting cavity quality factor, and automatic compensation of detuning due to Lorentz forces. This paper explains the functionality of these automation tools, details about their implementation, and shows the experience acquired during the last 9mA ILC test which took place at DESY in February 2012. The benefit of these algorithms and the R&D results these automation tools have permitted will be clearly explained.