Author: Barranco, J.
Paper Title Page
MOPWO010 Machine Protection Studies for a Crab Cavity in the LHC 906
  • B. Yee-Rendon, R. Lopez-Fernandez
    CINVESTAV, Mexico City, Mexico
  • T. Baer, J. Barranco, R. Calaga, A. Marsili, R. Tomás, F. Zimmermann
    CERN, Geneva, Switzerland
  Funding: US-LARP and CONACYT
Crab cavities (CCs) apply a transverse kick that rotate the bunches so as to have a head-on collision at the interaction point (IP). Such cavities were successfully used to improve the luminosity of KEKB. They are also a key ingredient of the HL-LHC project to increase the luminosity of the LHC. As CCs can rapidly change the particle trajectories, machine protection studies are required to assess the beam losses due to fast CC failures. In this paper, we discuss the effect of rapid voltage or phase changes in a CC for the HL-LHC layout using measured beam distributions from the present LHC.
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.  
TUPME051 CLIC Final Focus System Alignment and Magnet Tolerances 1682
  • J. Snuverink, J. Barranco, H. Garcia, Y.I. Levinsen, D. Schulte, R. Tomás
    CERN, Geneva, Switzerland
  The design requirements for the magnets in the Compact Linear Collider (CLIC) Final Focus System (FFS) are very stringent. In this paper the sensitivity for the misalignment and the magnetic imperfections for the different magnets in the FFS and the crab cavity are presented. Possible mitigation methods are discussed.  
WEPEA076 Comparison of Taylor Maps with Radio Frequency Multipoles in a Thin Lens 6D Tracking Code 2687
  • D.R. Brett, R. Appleby
    UMAN, Manchester, United Kingdom
  • J. Barranco, R. De Maria, R. Tomás
    CERN, Geneva, Switzerland
  Funding: HiLumi LHC Design Study is part of the High Luminosity LHC project and is part funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.
SixTrack is a general purpose 6D thin lens tracking code used for dynamic aperture studies. In the high luminosity LHC upgrade it is proposed that crab cavities are used to enhance the luminosity. In this study, for the current proposed optics, we consider the use of RF multipoles and Taylor maps as methods to simulate crab cavity elements in the lattice.
MOPWO028 Recent Developments and Future Plans for SixTrack 948
  • R. De Maria, R. Bruce, R. Calaga, L. Deniau, M. Fjellstrom, M. Giovannozzi, L. Lari, Y.I. Levinsen, E. McIntosh, A. Mereghetti, D. Pastor Sinuela, S. Redaelli, H. Renshall, A. Rossi, F. Schmidt, R. Tomás, V. Vlachoudis
    CERN, Geneva, Switzerland
  • R. Appleby, D.R. Brett
    UMAN, Manchester, United Kingdom
  • D. Banfi, J. Barranco
    EPFL, Lausanne, Switzerland
  • B. Dalena
    CEA/IRFU, Gif-sur-Yvette, France
  • L. Lari
    IFIC, Valencia, Spain
  • V. Previtali
    Fermilab, Batavia, USA
  • G. Robert-Demolaize
    BNL, Upton, Long Island, New York, USA
  Funding: The HiLumi LHC Design Study is included in the HL-LHC project and is partly funded by the European Commission within the Framework Programme 7 Capacities Specific Programme, Grant Agreement 284404.
SixTrack is a symplectic 6D tracking code routinely used to simulate single particle trajectories in high energy circular machines like the LHC and RHIC. The paper presents the developments recently implemented and those foreseen for extending the physics models: exact Hamiltonian, different ions and charge states, RF multipoles, non-linear fringe fields, Taylor maps, e-lenses, ion scattering. Moreover new functionalities are also added like variable number of tracked particles, time dependent strengths, GPU computations with a refactoring of the core structure. The developments will benefit studies on the LHC and SPS, for collimation efficiency, ion operations, failure scenarios and HL-LHC design.