Author: Gorda, O.E.
Paper Title Page
WEPC054 Amplitude Dependent Tune Spread in the CR Operated as an Antiproton Collector 2136
 
  • A. Dolinskii, C. Dimopoulou, O.E. Gorda, S.A. Litvinov, F. Nolden, M. Steck
    GSI, Darmstadt, Germany
 
  The Collector Ring is planned to be built for efficient cooling of antiprotons and rare isotopes beams. In order to accept hot antiproton beams coming from a separator large aperture magnets are required. This paper examines the effects which, may influence on the beam dynamic because of both large both betatron amplitude oscillations (240 mm mrad) and momentum spread (6%). Using analytic expressions the amplitude-dependent tune shifts driven by sextupole magnets, fringe field of quadrupole magnets and kinematics effects have been calculated. The results are compared with numerical simulations. Tracking studies for the CR operated as an antiproton collector have been performed considering the real shape of the magnetic field of the wide aperture quadrupole. We report on quantitative studies of the effects on the tune spread and its influence on the beam losses.  
 
WEPC055 Beam Orbit and Power Converter Stability at the CR 2139
 
  • A. Dolinskii, C. Dimopoulou, O.E. Gorda, S.A. Litvinov, F. Nolden, M. Steck, H. Weick
    GSI, Darmstadt, Germany
 
  For the isochronous mode operation of the CR with reference to have good properties of the mass measurements we study the sources of the beam orbit fluctuation and as consequence power converter requirements for the CR operated at BR=13 Tm. This papaer presents a summary of the different factors causing beam orbit variation, which leads to reduction of the mass measurements precision. The requirements to the power converters have been addressed.  
 
WEPC056 Beam Test of Slow Extraction from the ESR 2142
 
  • A. Dolinskii, C. Dimopoulou, O.E. Gorda, S.A. Litvinov, F. Nolden, M. Steck
    GSI, Darmstadt, Germany
 
  In the frame of a dedicated ESR machine development the conventional third order resonant slow extraction was theoretically investigated and experimentally tested. The possibility to extract a beam from the ESR by preparing a resonant closed orbit, which has strong nonlinear characteristics, was demonstrated. A third-integer resonance slow extraction has been adopted for the 100 MeV/u Ar beam.  
 
WEPC058 Field Properties of the ESR Magnets and their Influence on Beam Optics 2148
 
  • O.E. Gorda, C. Dimopoulou, A. Dolinskii, S.A. Litvinov, F. Nolden, M. Steck
    GSI, Darmstadt, Germany
 
  Machine experiments at the experimental storage ring (ESR) demonstrated that the ring acceptance is strongly restricted by field errors. Higher-order field harmonics of the dipole and quadrupole magnets have been calculated and then used in particle tracking simulations in order to find out the dynamic aperture of the ESR. To benchmark the results of numerical calculations, betatron tune measurements have been performed with a uranium beam at the energy of 400 MeV/u. The results of the magnetic field simulations for the ESR magnets and a comparison between the measured and calculated tune behavioгr are presented.  
 
WEPC162 Investigations into Non-linear Beam Dynamics in Electrostatic Storage Rings 2361
 
  • D. Newton, C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • O.E. Gorda
    MPI-K, Heidelberg, Germany
  • D. Newton
    The University of Liverpool, Liverpool, United Kingdom
  • A.I. Papash
    JINR, Dubna, Moscow Region, Russia
 
  Funding: Work supported by STFC, the Helmholtz Association and GSI under contract VH-NG-328.
Electrostatic (ES) storage rings provide a cost-effective solution to the problem of confining low energy (beta << 1) charged particles and ions, whilst controlling the beam properties, for use in multi-pass experiments. However, compared to magnetic storage rings, the beam dynamics calculations for an ES ring show subtle differences, especially in the coupling of the longitudinal and transverse velocities and in the focusing properties of bending element fringe fields. Using the nominal design for a prototype ES ring, realistic trajectories (including fringe fields and non-linear field components) have been calculated and a comparison is made with linear lattice simulations. The effect of the non-linear field components on the beam parameters is discussed.