Author: Schulz, S.
Paper Title Page
THP076 Measurements of the Timing Stability at the FLASH1 Seeding Experiment 913
  • C. Lechner, A. Azima, M. Drescher, L.L. Lazzarino, Th. Maltezopoulos, V. Miltchev, T. Plath, J. Rönsch-Schulenburg, J. Roßbach, M. Wieland
    Uni HH, Hamburg, Germany
  • S. Ackermann, J. Bödewadt, H. Dachraoui, N. Ekanayake, B. Faatz, M. Felber, K. Honkavaara, T. Laarmann, J.M. Mueller, H. Schlarb, S. Schreiber, S. Schulz
    DESY, Hamburg, Germany
  • G. Angelova Hamberg
    Uppsala University, Uppsala, Sweden
  • K.E. Hacker, S. Khan, R. Molo
    DELTA, Dortmund, Germany
  • P.M. Salen, P. van der Meulen
    FYSIKUM, AlbaNova, Stockholm University, Stockholm, Sweden
  Funding: Supported by Federal Ministry of Education and Research of Germany under contract No. 05K10PE1, 05K10PE3, 05K13GU4 and 05K13PE3 and the German Research Foundation programme graduate school 1355.
For seeding of a free-electron laser, the spatial and temporal overlap of the seed laser pulse and the electron bunch in the modulator is critical. To establish the temporal overlap, the time difference between pulses from the seed laser and spontaneous undulator radiation is reduced to a few pico-seconds with a combination of a photomultiplier tube and a streak camera. Finally, for the precise overlap the impact of the seed laser pulses on the electron bunches is observed. In this contribution, we describe the current experimental setup, discuss the techniques applied to establish the temporal overlap and analyze its stability.
THP090 Femtosecond Timing Distribution for the European XFEL 945
  • C. Sydlo, M.K. Czwalinna, M. Felber, C. Gerth, T. Lamb, H. Schlarb, S. Schulz, F. Zummack
    DESY, Hamburg, Germany
  • S. Jabłoński
    Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
  Accurate timing synchronization on the femtosecond timescale is an essential installation for time-resolved experiments at free-electron lasers (FELs) such as FLASH and the upcoming European XFEL. To date the required precision levels can only be achieved by a laser-based synchronization system. Such a system has been successfully deployed at FLASH and is based on the distribution of femtosecond laser pulses over actively stabilized optical fibers. Albeit its maturity and proven performance this system had to undergo a major redesign for the upcoming European XFEL due to the enlarged number of stabilized optical fibers and an increase by a factor of up to 10 in length. The experience and knowledge gathered from the operation of the optical synchronization system at FLASH has led to an elaborate and modular precision instrument which can stabilize polarization maintaining fibers for highest accuracy as well as economic single mode fibers for shorter lengths. This paper reports on the laser-based synchronization system focusing on the active fiber stabilization units for the European XFEL, discusses major complications, their solutions and and the most recent performance results.