Author: Holma, J.
Paper Title Page
TUPPC086 Conceptual Design of the CLIC damping rings 1368
 
  • Y. Papaphilippou, F. Antoniou, M.J. Barnes, S. Calatroni, P. Chiggiato, R. Corsini, A. Grudiev, J. Holma, T. Lefèvre, M. Martini, M. Modena, N. Mounet, A. Perin, Y. Renier, G. Rumolo, S. Russenschuck, H. Schmickler, D. Schoerling, D. Schulte, M. Taborelli, G. Vandoni, F. Zimmermann
    CERN, Geneva, Switzerland
  • C. Belver-Aguilar, A. Faus-Golfe
    IFIC, Valencia, Spain
  • A. Bernhard
    KIT, Karlsruhe, Germany
  • M.J. Boland
    ASCo, Clayton, Victoria, Australia
  • A.V. Bragin, E.B. Levichev, S.V. Sinyatkin, P. Vobly, K. Zolotarev
    BINP SB RAS, Novosibirsk, Russia
  • M. Korostelev
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • E. Koukovini
    EPFL, Lausanne, Switzerland
  • M.A. Palmer
    CLASSE, Ithaca, New York, USA
  • M.T.F. Pivi, S.R. Smith
    SLAC, Menlo Park, California, USA
  • R.P. Rassool, K.P. Wootton
    The University of Melbourne, Melbourne, Australia
  • L. Rinolfi
    JUAS, Archamps, France
  • A. Vivoli
    Fermilab, Batavia, USA
 
  The CLIC damping rings are designed to produce unprecedentedly low-emittances of 500 nm and 5 nm normalized at 2.86 GeV, in all beam dimensions with high bunch charge, necessary for the performance of the collider. The large beam brightness triggers a number of beam dynamics and technical challenges. Ring parameters such as energy, circumference, lattice, momentum compaction, bending and super-conducting wiggler fields are carefully chosen in order to provide the target emittances under the influence of intrabeam scattering but also reduce the impact of collective effects such as space-charge and coherent synchrotron radiation. Mitigation techniques for two stream instabilities have been identified and tested. The low vertical emittance is achieved by modern orbit and coupling correction techniques. Design considerations and plans for technical system, such as damping wigglers, transfer systems, vacuum, RF cavities, instrumentation and feedback are finally reviewed.  
 
THPPD076 Evaluation of Components for the High Precision Inductive Adder for the CLIC Damping Rings 3692
 
  • J. Holma, M.J. Barnes
    CERN, Geneva, Switzerland
 
  The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse generators for the damping ring kickers must provide extremely flat, high-voltage pulses. The specifications for the extraction kickers of the CLIC damping rings are particularly demanding: the flattop of the output pulse must be 160 ns duration, 12.5 kV and 250 A, with a combined ripple and droop of not more than ±0.02 %. An inductive adder allows the use of different modulation techniques and is therefore a very promising approach to meeting the specifications. In addition to semiconductors working in their saturated region, semiconductors working in their linear region are needed for applying analogue modulation techniques. Simulations have been carried out to define component specifications for the inductive adder: this paper reports the results of tests and measurements of various components.