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Lorentz, B.

Paper Title Page
MOPC111 Lattice Studies for Spin-filtering Experiments at COSY and AD 322
 
  • A. Garishvili, A. N. Nass, E. Steffens
    University of Erlangen-Nürnberg, Physikalisches Institut II, Erlangen
  • A. Lehrach, B. Lorentz, R. Maier, F. Rathmann, R. Schleichert, H. Ströher
    FZJ, Jülich
  • P. Lenisa, M. Statera
    INFN-Ferrara, Ferrara
  • S. A. Martin
    UGS, Langenbernsdorf
 
  In the framework of the FAIR project, the PAX collaboration has proposed a research program based on polarized antiprotons. Polarized antiprotons are to be produced by spin-dependent attenuation on a polarized hydrogen target. For a better understanding of this mechanism it is planned to perform Spin-Filtering studies with protons at COSY (Jülich). In a second phase, it is envisioned to study Spin-Filtering with antiprotons at the AD (CERN). Which will allow for the determination of the total spin-dependent transverse and longitudinal cross sections. In order to achieve the required long storage times, a storage ring section has to be developed which minimizes the spin-independent losses due to Coulomb scattering. The Coulomb-loss cross section for single scattering losses at fixed energy is proportional to the acceptance angle. Therefore, at the target point the beta functions should be as small as possible. Fot the 'low-beta' section, superconducting quadrupole magnets are utilized. It is composed of two (COSY) and three (AD) SC quadrupoles on each side of the target. Results of the lattice studies and requirements for the superconducting quadrupole magnets will be discussed  
MOPC112 HESR Linear Lattice Design 325
 
  • B. Lorentz, A. Lehrach, R. Maier, D. Prasuhn, H. Stockhorst, R. Tölle
    FZJ, Jülich
 
  The High Energy Storage Ring (HESR) is a part of the future Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt. The ring is used for hadron physics experiments with a pellet target and the PANDA detector, and will supply antiprotons of momenta from 1.5 GeV/c to 15 GeV/c. The ring will consist of two 180 degree bending sections (arcs) of 157 m length, each, and two 132 m long straight sections. In one of the straight sections the PANDA experiment will be installed, the other straight section will be equipped with a High Energy Electron Cooler. A longitudinal and transverse stochastic cooling system will be used in the momentum range from 3.8 GeV/c to 15 GeV/c. Adjustment of beta functions at target and electron cooler, to achieve highest beam lifetimes, most efficient cooling and highest luminosities are the main design requirements. The basic design consists of FODO cell structures in the arcs. The arc quadrupole magnets are grouped into four families, to allow a flexible adjustment of transition energy, horizontal and vertical tune, and dispersion. The details of the linear lattice and operation modes will be discussed in this presentation.  
THPC076 Closed Orbit Correction and Sextupole Compensation Schemes for Normal-conducting HESR 3161
 
  • D. M. Welsch, A. Lehrach, B. Lorentz, R. Maier, D. Prasuhn, R. Tölle
    FZJ, Jülich
 
  The High Energy Storage Ring (HESR) will be part of the future Facility for Antiproton and Ion Research (FAIR) located at GSI in Darmstadt, Germany. The HESR will be operated with antiprotons in the momentum range from 1.5 to 15 GeV/c, which makes a long beam life time and a minimum of particle losses crucial. This and the demanding requirements of the PANDA experiment lead to the necessity of a good orbit correction and an effective multipole compensation. We developed a closed orbit correction scheme and tested it with Monte Carlo simulations. We assigned different sets of angular and spatial errors to all elements (magnets, bpms, etc.) within the lattice of the HESR. For correction we applied the orbit response matrix method. We carried out investigations concerning higher-order multipoles and created a scheme for chromaticity correction and compensation of arising resonances utilising analytic formulae and dynamic aperture calculations. In this presentation we give an overview of the correction and compensation schemes and of the corresponding results.