Author: Ruber, R.J.M.Y.
Paper Title Page
MOEPPB001 RF-breakdown Kicks at the CTF3 Two-beam Test Stand 73
 
  • A. Palaia, M. Jacewicz, T. Muranaka, R.J.M.Y. Ruber, V.G. Ziemann
    Uppsala University, Uppsala, Sweden
  • W. Farabolini
    CEA/DSM/IRFU, France
 
  The measurement of the effects of RF-breakdown on the beam in CLIC prototype accelerator structures is one of the key aspects of the CLIC two-beam acceleration scheme being addressed at the Two-beam Test Stand (TBTS) at CTF3. RF-breakdown can randomly cause energy loss and transverse kicks to the beam. Transverse kicks have been measured by means of a screen intercepting the beam after the accelerator structure. In correspondence of a RF-breakdown we detect a double beam spot which we interpret as a sudden change of the beam trajectory within a single beam pulse. To time-resolve such effect, the TBTS has been equipped with five inductive Beam Position Monitors (BPMs) and a spectrometer line to measure both relative changes of the beam trajectory and energy losses. Here we discuss the methodology used and we present the latest results of such measurements.  
 
TUPPR019 High Power Operation with Beam of a CLIC PETS Equipped with ON/OFF Mechanism 1852
 
  • I. Syratchev, R. Corsini, A. Dubrovskiy, P. Skowroński
    CERN, Geneva, Switzerland
  • R.J.M.Y. Ruber
    Uppsala University, Uppsala, Sweden
 
  One of the feasibility issues of the CLIC two-beam scheme is the possibility of rapidly switching off the RF power production in individual Power Extraction and Transfer Structures (PETS) in case of breakdowns, either in the PETS or one of the main beam accelerating structures. The proposed solution is to use a variable external reflector connected to the PETS. When activated, this scheme allows us to manipulate gradually the RF power transfer to the accelerating structure and to reduce the RF power production in the PETS itself by a factor of 4. Recently the first operation of the Two Beam Test Stand (TBTS) PETS equipped with an on-off mechanism has been performed in CTF3. In this paper we will present the results of the PETS operation when powered by the drive beam up to high peak power levels (>100 MW) and compare them to expectations.