Author: Andersson, A.
Paper Title Page
MOPME077 Electro-0ptical Bunch Profile Measurement at CTF3 658
 
  • R. Pan, A. Andersson, W. Farabolini, A. Goldblatt, T. Lefèvre, M. Martyanov, S. Mazzoni, S.F. Rey, L. Timeo
    CERN, Geneva, Switzerland
  • W.A. Gillespie, R. Pan, D.A. Walsh
    University of Dundee, Nethergate, Dundee, Scotland, United Kingdom
  • S.P. Jamison
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
 
  A new electro-optic bunch profile monitor has recently been installed in CLIC Test Facility 3 at CERN. The monitor is based on an electro-optic spectral decoding scheme which reconstructs the longitudinal profile of the electron bunch by measuring its Coulomb field. The system uses a 780 nm fibre laser system, transported over a 20m long distance to the interaction chamber, where a ZnTe crystal is positioned close to the beam. The assembly also contains a traditional OTR screen, which is coupled to a second optical line and used to adjust the temporal overlap between the laser and the electron pulse. This paper presents the detection system in detail, as well as reporting on the first measurements performed with beam.  
 
TUPFI040 Experimental Verification of the CLIC Two-Beam Acceleration Technology in CTF3 1436
 
  • P. Skowroński, A. Andersson, J. Barranco, B. Constance, R. Corsini, S. Döbert, A. Dubrovskiy, W. Farabolini, E. Ikarios, R.L. Lillestøl, T. Persson, F. Tecker
    CERN, Geneva, Switzerland
  • W. Farabolini
    CEA/DSM/IRFU, France
  • E. Ikarios
    National Technical University of Athens, Athens, Greece
  • M. Jacewicz, A. Palaia, R.J.M.Y. Ruber
    Uppsala University, Uppsala, Sweden
  • R.L. Lillestøl
    University of Oslo, Oslo, Norway
  • T. Persson
    Chalmers University of Technology, Chalmers Tekniska Högskola, Gothenburg, Sweden
 
  The Compact Linear Collider (CLIC) International Collaboration is pursuing an extensive R&D program towards a multi-TeV electron-positron collider. In particular, the development of two beam acceleration technology is the focus of the CLIC test facility CTF3. In this paper we summarize the most recent results obtained at CTF3: the results of the studies on the drive beam generation are presented, the achieved two beam acceleration performance is reported and the measured break-down rates and related observations are summarized. The stability of deceleration process performed over 13 subsequent modules and the comparison of the obtained results with the theoretical expectations are discussed. We also outline and discuss the future experimental program.  
 
TUPME039 The Drive Beam Phase Stability in CTF3 and its Relation to the Bunch Compression Factor 1655
 
  • E. Ikarios, A. Andersson, J. Barranco, B. Constance, R. Corsini, A. Gerbershagen, T. Persson, P. Skowroński, F. Tecker
    CERN, Geneva, Switzerland
 
  The proposed Compact Linear Collider (CLIC) is based on a two-beam acceleration scheme. The energy needed to accelerate a low intensity "main" beam is provided by a high intensity, low energy "drive" beam. The precision and stability of the phase relation between two beams is crucial for the performance of the scheme. The tolerable phase jitter is 0.2 deg rms at 12GHz. For this reason it is fundamental to understand the main possible causes of the drive beam timing jitter. Experimental work aimed at such understanding was done in the CLIC Test Facility (CTF3) where a drive beam with characteristics similar to the CLIC one is produced. Several phase measurements allowed us to conclude that the main source of phase jitter is energy jitter of the beam transformed and amplified into phase jitter when passing through a magnetic chicane. This conclusion is supported by measurements done with different momentum compaction values in the chicane. In this paper the results of these several phase measurements will be presented and compared with expectations.  
 
WEOBB203 Design of Phase Feed Forward System in CTF3 and Performance of Fast Beam Phase Monitors 2097
 
  • P. Skowroński, A. Andersson, A. Gerbershagen, E. Ikarios, J. Roberts
    CERN, Geneva, Switzerland
  • P. Burrows, G.B. Christian, A. Gerbershagen, C. Perry, J. Roberts
    JAI, Oxford, United Kingdom
  • P. Burrows, G.B. Christian, A. Gerbershagen, C. Perry
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
  • A. Ghigo, F. Marcellini
    INFN/LNF, Frascati (Roma), Italy
  • E. Ikarios
    National Technical University of Athens, Athens, Greece
 
  Funding: Work supported by the European Commission under the FP7 Research Infrastructures project Eu- CARD, grant agreement no. 227579
The CLIC two beam acceleration technology requires a drive beam phase stability of better than 0.3 deg rms at 12 GHz, corresponding to a timing stability below 50 fs rms. For this reason the CLIC design includes a phase stabilization feed-forward system. It relies on precise beam phase measurement and its subsequent correction in a chicane with help of fast kickers. A prototype of such a system is being installed in CLIC Test Facility CTF3. In this paper we describe in detail its design and implementation. Additionally, we present and discuss the performance of the precision phase monitor prototypes installed at the end of the CTF3 linac, measured with the drive beam.
We would like to acknowledge support of G.Sensolini, A.Zolla (INFN/LNF Frascati), N.S.Chritin and J-M.Scigliuto (CERN) in design and fabrication of components.
 
slides icon Slides WEOBB203 [6.770 MB]