Author: Previtali, V.
Paper Title Page
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.
 
 
MOPWO035 Layouts for Crystal Collimation Tests at the LHC 966
 
  • D. Mirarchi, S. Redaelli, W. Scandale
    CERN, Geneva, Switzerland
  • D. Mirarchi
    The Imperial College of Science, Technology and Medicine, London, United Kingdom
  • V. Previtali
    Fermilab, Batavia, USA
 
  Various studies have been carried out in the past years regarding crystal collimation for the LHC. A new extensive campaign of simulations was performed to determine optimum layouts for beam tests at the LHC. The layouts are determined based on semi-analytical models for the dynamics of channeled particles. Detailed SixTrack tracking with all collimators of the ring are then used to validate the different options. An overview of the ongoing studies is given. Comparative studies between the present collimation system, the crystal collimation system, and different crystal collimation layout are presented.  
 
MOPWO043 Hollow Electron Lens Simulation for the SPS 990
 
  • V. Previtali, G. Stancari, A. Valishev
    Fermilab, Batavia, USA
  • S. Redaelli
    CERN, Geneva, Switzerland
 
  Funding: Fermilab is operated by Fermi Research Alliance, LLC, Contract No. DE-AC02-07CH11359 with the United States Dep. of Energy. This work was supported by the US LHC Accelerator Research Program (LARP).
The hardware of the Tevatron hollow electron lens, which has been used in the past for collimation purposes, is presently available. Possible applications of similar devices in the LHC are under evaluation, but a realistic date for installation of electron lenses in the LHC would be not earlier than the machine shutdown scheduled for 2018. We investigated the possibility of beam tests with the available hardware in the meantime in the SPS. This article aims to answer this question by presenting the results of dedicated numerical simulations.
 
 
MOPWO044 Numerical Simulations of a Hollow Electron Lens as a Scraping Device for the LHC 993
 
  • V. Previtali, G. Stancari, A. Valishev
    Fermilab, Batavia, USA
  • S. Redaelli
    CERN, Geneva, Switzerland
 
  Funding: Fermilab is operated by Fermi Research Alliance, LLC, Contract No.DE-AC02-07CH11359 with the United States Dep. of Energy. This work was partially supported by US LHC Accelerator Research Program(LARP)
The use of hollow electron beam lens for scraping high energy proton beams has been extensively tested at Fermilab's Tevatron collider. In order to evaluate a possible application of a similar a device in the LHC, a dedicated new routine has been implemented in the standard 6D tracking code used at CERN for the design of the LHC collimation system. The effects of a finite length cylinder of electrons encompassing the main proton beam and traveling in the opposite direction is described in the routine. Realistic electron distributions, including measured radial imperfections, have been included in the model. Various operating modes have been simulated for the 7 TeV machine operation with sextupoles and octupoles included. The loss rate caused by the electron lens has been studied through an extended simulation campaign; the obtained halo removal rates for the different electron lens operating modes are presented.