Author: Felber, E.P.
Paper Title Page
WEB04 Laser-to-RF Synchronization with Femtosecond Precision 1
  • T. Lamb, Ł. Butkowski, E.P. Felber, M. Felber, M. Fenner, S. Jabłoński, T. Kozak, J.M. Müller, P. Prędki, H. Schlarb, C. Sydlo, M. Titberidze, F. Zummack
    DESY, Hamburg, Germany
  Optical synchronization systems are already in regular operation in many FELs, or they will eventually be implemented in the future. In FLASH and the European XFEL, phase-stable optical reference signals are provided by a pulsed optical synchronization system in order to achieve low timing jitter FEL performance. The generation of phase-stable RF signals from a pulsed optical synchronization system is still a field of active research. The optical reference module (REFM-OPT), designed at DESY for operation in both FELs, employs a laser-to-RF phase detector, based on an integrated Mach-Zehnder interferometer. The phase drift of the 1.3 GHz RF reference signals with respect to the optical pulses is measured and actively corrected within the REFM-OPT at multiple locations in the accelerator. Therefore the REFM-OPT provides phase stable 1.3 GHz RF reference signals at these locations. The short-term and long-term performance in the accelerator tunnel of the European XFEL is presented and carefully reviewed.  
slides icon Slides WEB04 [5.679 MB]  
MicroTCA.4 -Based Control for the Optical Synchronization System at the European XFEL  
  • M. Felber, E.P. Felber, M. Fenner, C. Gerth, M. Heuer, T. Kozak, T. Lamb, J.M. Müller, K.P. Przygoda, H. Schlarb, C. Sydlo, F. Zummack
    DESY, Hamburg, Germany
  The optical synchronization system at the European XFEL will serve as femtosecond-stable reference throughout the 3.5 km long facility. Its operation and performance is essential for the success of pump-probe experiments, first by enabling the LLRF system to stabilize the electron bunch arrival time and thereby the FEL X-ray pulse timing, and second by synchronizing the experimental laser with fs precision. The electronic hardware is realized in various MicroTCA.4 modules. Most of them are specially designed for this application but yet commercially available on the market due to licensing agreements between DESY and industry partners. In this paper we present the applied modules, the topology of the new systems and review the first operational experience.