Author: Wamsat, T.
Paper Title Page
TUPRB019 Collimator Performance Study at the European XFEL 1717
 
  • S. Liu, F. Brinker, W. Decking, L. Fröhlich, N. Golubeva, T. Wamsat, J. Wilgen
    DESY, Hamburg, Germany
  
  Beam halo collimation is of great importance for the high repetition rate operation at the European XFEL and for the future CW machines. At the European XFEL several different types of collimators are installed at different locations of the beam line, which include the gun collimators, the bunch compressor collimators, and the main and supplementary collimators in the collimation section. Beam halo measurements have been performed using the wire scanners downstream of the main linac, which show that large part of beam halo is collimated by the gun collimator. Remaining losses in the collimation section are mainly due to misalignment. Alignment using orbit bumps in the collimation section is performed and presented in this paper.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPRB019  
About • paper received ※ 15 May 2019       paper accepted ※ 22 May 2019       issue date ※ 21 June 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPRB020 Status of the European XFEL 1721
 
  • W. Decking, F. Brinker, L. Fröhlich, R. Kammering, T. Limberg, S. Liu, D. Nölle, M. Omet, M. Scholz, T. Wamsat
    DESY, Hamburg, Germany
  
  The European XFEL is a Hard X-ray Free Electron Laser based on superconducting accelerator technology. In operation since 2017, it now serves 3 FEL beamlines simultaneously for user experiments. We will report on the present operation of the linear accelerator, the beam distribution to the various beamlines and the performance of the FEL radiators.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPRB020  
About • paper received ※ 15 May 2019       paper accepted ※ 17 May 2019       issue date ※ 21 June 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPRB075 Higher Order Mode Spectra Study of 3.9 GHz Superconducting Radio Frequency Cavities for the European XFEL 1840
 
  • L. Shi, S. Reiche
    PSI, Villigen PSI, Switzerland
  • N. Baboi, A. Sulimov, E. Vogel, T. Wamsat
    DESY, Hamburg, Germany
  • R.M. Jones, N.Y. Joshi
    UMAN, Manchester, United Kingdom
  • P. Pierini
    ESS, Lund, Sweden
  
  Funding: The work is part of EuCARD2 and was partly funded by the European Commission, GA 312453.
It is important to verify both by simulation and experiments the wakefields in superconducting radio frequency (SRF) cavities, which can degrade the electron beam quality considerably or impose excessive heat load if left undamped. In this paper, we investigate the Higher Order Mode (HOM) spectra of the 3.9 GHz SRF cavities, which are assembled in a cryogenic module and are used to linearize the longitudinal phase space of the electron beam in the injector of the European XFEL. The HOM spectra are significantly different from the ones from a single cavity due to the coupling of the modes amongst cavities. The measurements not only provide direct input for the beam dynamics studies but also for the beam instrumentation utilizing these modes. The mode spectra are also investigated with a number of numerical simulations and the comparison with measurements shows favorable agreement. 		 
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPRB075  
About • paper received ※ 13 May 2019       paper accepted ※ 23 May 2019       issue date ※ 21 June 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)