Author: El Khaldi, M.
Paper Title Page
WEPWO001 Power Couplers for XFEL 2310
  • W. Kaabi, M. El Khaldi, A. Gallas, P. Lepercq, C. Magueur, A. Variola, A. Verguet
    LAL, Orsay, France
  • W.-D. Möller
    DESY, Hamburg, Germany
  The LAL contribution to the XFEL project will be the delivery of 800 power couplers to equip 100 Cry-modules. The LAL’s tasks consist on the industrial monitoring and coupler quality control at two different production sites, in addition to the RF conditioning at LAL of the 800 produced couplers. The RF conditioning and all the coupler preparation process will be held in a 70m2 ISO5 clean room. An RF power station delivering 5MW, allow 8 couplers conditioning in the same time. Being in production control side and also RF conditioning one, the aim of LAL is to reach the rate of 8 couplers delivery per week, after a rump up phase. The starting of Coupler mass production is scheduled for beginning 2013.  
WEPFI005 Simulations and RF Measurements of the Fundamental and Higher Order Modes of the ThomX 500 MHz Cavity 2711
  • M. El Khaldi, I.V. Drebot, P. Lepercq, R. Marie, B. Mercier, T. Roulet, A. Variola, F. Wicek
    LAL, Orsay, France
  • H.D. Dias, M.D. Diop, M.E. El Ajjouri, R. Lopes, A. Loulergue, P. Marchand, F. Ribeiro, R. Sreedharan
    SOLEIL, Gif-sur-Yvette, France
  The RF system of the ThomX* storage ring consists in a 500 MHz single cell copper cavity of the ELETTRA type, powered with a 50 kW CW solid state amplifier, and the associated Low Level RF feedback and control loops. The low operating energy of 50 – 70 MeV makes the impedances of the cavity higher order modes (HOMs) particularly critical for the beam stability. Their parasitic effects on the beam can be cured by HOM frequency shifting techniques, based on a fine temperature tuning and a dedicated plunger. A typical cavity temperature stability of ± 0.05°C within a range from 35 up to 80 °C can be achieved by a precise control of its water cooling temperature. On the other hand, the tuning of the cavity fundamental mode is achieved by changing its axial length by means of a mechanical tuner. In order to insure a fine control of the HOM frequencies, a good knowledge of their characteristics is mandatory. The main parameters of the fundamental and of the HOMs up to 4 GHz have been calculated using the HFSS and CST MWS codes. Preliminary measurements results have been obtained and show a good agreement with the simulations.
* A.Variola, “The ThomX Project”, Proceedings of IPAC2011, San Sebastián, Spain