The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
TY - UNPB AU - Lockmann, N.M. AU - Gerth, C. AU - Schmidt, B. AU - Wesch, S. ED - Tavares, Daniel ED - Picoreti, Renan ED - Bruno, Gustavo ED - Marques, Sergio ED - Schaa, Volker R.W. TI - Non-invasive Longitudinal Profile Measurements of Electron Bunches Simultaneously to FEL Operation at MHz Rates J2 - Proc. of IBIC2020, Santos, Brazil, 14-18 September 2020 CY - Santos, Brazil T2 - International Beam Instrumentation Conference T3 - 9 LA - english AB - Hard X-ray FELs require ultra-short electron bunches with peak currents of several kiloamperes. Therefore, longitudinal bunch profile characterization with femtosecond resolution is essential for a successful operation and control of the accelerator as well as a wide field of photon experiments. The high electron beam energies of hard X-ray FELs enable non-invasive longitudinal form factor monitoring down to a few micrometers utilizing coherent diffraction radiation spectroscopy. For this purpose, a 4-staged grating spectrometer has been recently installed at European XFEL. Here, current profiles are reconstructed with femtosecond time resolution based on phase retrieval algorithms which are in excellent agreement to results obtained with a transverse deflecting structure. The fast pyroelectric detectors allow, for the first time, to measure the current profile of all bunches inside the bunch train with repetition rates of up to 2.2 MHz. The low latency electronic readout of the 120 channels of the spectrometer provides high potential for fast compression feedbacks and machine learning applications. PB - JACoW Publishing CP - Geneva, Switzerland ER -