Author: Jackson, F.
Paper Title Page
MOPPP021 Longitudinal Beam Dynamics at the ALICE Acclerator R&D Facility 610
  • F. Jackson, D. Angal-Kalinin, S.P. Jamison, J.W. McKenzie, T.T. Ng, Y.M. Saveliev, P.H. Williams
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  The ALICE facility is an energy recovery test accelerator whose applications include an IR-FEL and THz generation. Of primary importance to the performance of the main ALICE applications is the understanding and control of the longitudinal dynamics, which are less amenable to measurement than the transverse. The longitudinal dynamics of the beam evolve are studied in simulation and experiment in several areas of the machine. Simulations of the low energy injector where space charge and velocity bunching may occur are presented. Path length measurement using time-of-arrival monitors are carried out.  
MOPPP023 Effect of DC Photoinjector Gun Voltage on Beam Dynamics in ALICE ERL 616
  • Y.M. Saveliev, F. Jackson, J.K. Jones, J.W. McKenzie
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  The ALICE ERL employs a DC HV photoelectron gun as an electron source. As with other machines in this class, the electron beam is not always of perfect quality. This is aggravated by that the ALICE gun has been operated so far at lower 230kV voltage compared to the design value of 350kV due to hardware limitations. The “two beams” structure was observed and experimentally investigated and found to be the result of complex processes during initial stages of beam acceleration. The experimental observations and data will be compared with those obtained at a nominal 350kV gun voltage. An investigation of the effect of the DC photogun voltage on longitudinal and transverse beam dynamics will be presented and discussed.  
TUPPP067 Collimation System Design and Performance for the SwissFEL 1753
  • F. Jackson, J.L. Fernández-Hernando
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • D. Angal-Kalinin
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • H.-H. Braun, S. Reiche
    Paul Scherrer Institut, Villigen, Switzerland
  Electron beam collimation in the SwissFEL is required for protection of the undulators against radiation damage and demagnetization. The design for the SwissFEL collimation for the hard X-ray undulator (Aramis) includes transverse collimation in the final accelerating linac sections, plus an energy collimator in a post-linac chicane. The collimation system must provide efficient protection of the undulator for various machine modes providing varied final beam energy to the undulator. The performance of the transverse and energy collimation design is studied in simulations including evaluation of the transverse collimation for various beam energies and the effect of grazing particles on the energy collimator. Collimator wakefields are also considered.