Author: Braun, H.-H.
Paper Title Page
TUPPP067 Collimation System Design and Performance for the SwissFEL 1753
  • F. Jackson, J.L. Fernández-Hernando
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • D. Angal-Kalinin
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • H.-H. Braun, S. Reiche
    Paul Scherrer Institut, Villigen, Switzerland
  Electron beam collimation in the SwissFEL is required for protection of the undulators against radiation damage and demagnetization. The design for the SwissFEL collimation for the hard X-ray undulator (Aramis) includes transverse collimation in the final accelerating linac sections, plus an energy collimator in a post-linac chicane. The collimation system must provide efficient protection of the undulator for various machine modes providing varied final beam energy to the undulator. The performance of the transverse and energy collimation design is studied in simulations including evaluation of the transverse collimation for various beam energies and the effect of grazing particles on the energy collimator. Collimator wakefields are also considered.  
WEPPR076 Positron Options for the Linac-ring LHeC 3108
  • F. Zimmermann, O.S. Brüning, Y. Papaphilippou, D. Schulte, P. Sievers
    CERN, Geneva, Switzerland
  • H.-H. Braun
    Paul Scherrer Institut, Villigen, Switzerland
  • E.V. Bulyak
    NSC/KIPT, Kharkov, Ukraine
  • M. Klein
    The University of Liverpool, Liverpool, United Kingdom
  • L. Rinolfi
    JUAS, Archamps, France
  • A. Variola, Z.F. Zomer
    LAL, Orsay, France
  • V. Yakimenko
    BNL, Upton, Long Island, New York, USA
  The full physics program of a future Large Hadron electron Collider (LHeC) requires both pe+ and pe- collisions. For a pulsed 140-GeV or an ERL-based 60-GeV Linac-Ring LHeC this implies a challenging rate of, respectively, about 1.8·1015 or 4.4·1016 e+/s at the collision point, which is about 300 or 7000 times the past SLC rate. We consider providing this e+ rate through a combination of measures: (1) Reducing the required production rate from the e+ target through colliding e+ (and the LHC protons) several times before deceleration, by reusing the e+ over several acceleration/deceleration cycles, and by cooling them, e.g., with a compact tri-ring scheme or a conventional damping ring in the SPS tunnel. (2) Using an advanced target, e.g., W-granules, rotating wheel, sliced-rod converter, or liquid metal jet, for converting gamma rays to e+. (3) Selecting the most powerful of several proposed gamma sources, namely Compton ERL, Compton storage ring, coherent pair production in a strong laser, or high-field undulator radiation from the high-energy lepton beam. We describe the various concepts, present example parameters, estimate the electrical power required, and mention open questions.  
FRYAP01 The Future of X-ray FELs 4180
  • H.-H. Braun
    Paul Scherrer Institut, Villigen, Switzerland
  Recent years have brought enormous progress with X-ray FELs. With LCLS and SACLA two facilities with quite different technological approaches have shown the feasibility of SASE FELs in the hard X-ray regime while the SASE FEL FLASH and the recently commissioned laser seeded FEL FERMI@ELETTRA provide coherent light beams of unprecedented brightness at EUV and soft X-ray wavelength. First user experiments at these facilities demonstrate the vast scientific potential of this new type of instrument and have accelerated and triggered R&D and planning for other facilities of its kind worldwide. Projects under construction or in advanced stage of planning are European XFEL, LCLS II, SwissFEL, PAL XFEL, Shanghai XFEL and NGLS. Worldwide R&D efforts for XFELs try to improve performance and reduce size and cost. Focuses are on injector, linac and undulator technologies as well as on FEL seeding methods.  
slides icon Slides FRYAP01 [24.324 MB]