Author: Atkinson, T.
Paper Title Page
THPC108 Commissioning of the 50 MeV Preinjector Linac for the BESSY II Facility 3140
  • T. Atkinson, M. Helmecke, D. Schüler, E. Weihreter
    HZB, Berlin, Germany
  • V. Dürr
    BESSY GmbH, Berlin, Germany
  • D. Jousse, J.-L. Pastre, A.S. Setty
    THALES, Colombes, France
  A turn key 50MeV linac manufactured by Thales has been installed in the BESSY II facility. This linac will replace the existing Microtron injector in the near future to provide more flexible bunch population patterns for the femto-slicing operation mode and a higher single bunch intensity for top-up injection. This paper describes the essential problems which have been faced during commissioning and presents the main results obtained in the site acceptance tests including the measurement of beam emittance and energy spread.  
THPO024 Development of a Non-Linear Kicker System to Facilitate a New Injection Scheme for the BESSY II Storage Ring 3394
  • O. Dressler, T. Atkinson, M. Dirsat, P. Kuske
    HZB, Berlin, Germany
  • H. Rast
    DELTA, Dortmund, Germany
  Top-Up injections without noticeable motion of the stored beam is a challenge. The common method of beam accumulation with a local bump formed by four independent pulsed dipole kicker magnets usually causes beam oscillations. The matching of the four independent kicker systems regarding pulse jitters and shapes is technologically limited. Afterward the beam excitation was reduced more when two kicker magnets on each side of the septum were powered in series by one pulser unit. An even more promising approach is to adopt an alternative injection method deploying a single non-linear kicker magnet with zero Bx,y-field in the center and an off-axis maximum, By, which is horizontally displaced by 10-12 mm. There the injected beam gets kicked and looses half of its transverse momentum. Such a magnet was designed and built as a short in-vacuum magnet with a small vertical gap height. For first beam tests the kicker was placed in the second straight section after the injection point, and the 1.5 μs pulse was designed to deflect the 1.72 GeV beam by 1 mrad. In this paper, the calculations of the magnetic fields, the mechanical design as well as the electrical pulser circuit are described.
*New injection scheme using a pulsed quadrupole magnet in electron storage rings, Kentaro Harada, PHYSICAL REVIEW SPECIAL TOPICS - AB 10, 123501 (2007)