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Maier, R.

Paper Title Page
MOPCH084 From COSY to HESR 226
 
  • D. Prasuhn, J. Dietrich, A. Lehrach, B. Lorentz, R. Maier, H. Stockhorst
    FZJ, Jülich
 
  The High Energy Storage Ring (HESR) at the proposed Facility for Antiproton and Ion Research (FAIR) puts strong demands on quality and intensity of the stored antiproton beam in the presence of thick internal targets. The existing synchrotron and storage ring COSY in Juelich can be seen as a smaller model of the HESR. In this paper we will discuss possible benchmarking experiments at COSY, involving effects like beam cooling, target heating, intra-beam scattering, etc. The aim of these experiments is to support the design work for the HESR and ensure that the specified beam conditions can be achieved.  
MOPCH086 Stochastic Cooling for the HESR at the GSI-FAIR Complex 231
 
  • H. Stockhorst, B. Lorentz, R. Maier, D. Prasuhn
    FZJ, Jülich
  • T. Katayama
    CNS, Saitama
 
  The High-Energy Storage Ring (HESR) of the future International Facility for Antiproton and Ion Research (FAIR) at the GSI in Darmstadt is planned as an anti-proton cooler ring in the momentum range from 1.5 to 15 GeV/c. An important and challenging feature of the new facility is the combi-nation of phase space cooled beams with internal targets. The required beam parameters and intensities are prepared in two operation modes: the high luminosity mode with beam intensities up to 1011 and the high reso-lution mode with 1010 anti-protons cooled down to a relative momentum spread of only a few 10-5. In addition to electron cooling, transverse and longitudinal stochastic cooling are envisaged to accomplish these goals. It is shown how the great benefit of the stochastic cooling system to adjust the cooling force in all phase planes independently is utilized to achieve the requested beam spot and the high momentum resolution at the internal target within reasonable cooling down times for both HESR modes even in the presence of intra-beam scattering. A numerical and analytical approach to the Fokker-Planck equation for longitudinal filter cooling has been carried out.  
TUPLS044 The 3D Beam Dynamics with the Space Charge in the Low and Middle Energy Super-conducting Option of HIPPI 1594
 
  • N.E. Vasyukhin, R. Maier, Y. Senichev, R. Tölle
    FZJ, Jülich
 
  For the low and middle energy of the High Intensity Proton Pulse Injector (HIPPI), a superconducting option is considered.The 3D beam dynamics simulation results in the slot and the finger-slot sections covering the energy range from 3 to 160 MeV are presented. The optimization aim is the increase of beam current together with the reduction of emittance growth, beam losses and costs. The slot structure is compared with the conventional spoke structure.  
TUPLS087 Recent Gains in Polarized Beam Intensities for the Cooler Synchrotron COSY at Jülich 1705
 
  • R. Gebel, O. Felden, R. Maier, P. von Rossen
    FZJ, Jülich
 
  Since January 1996, the cyclotron JULIC operates as the injector of H(-) or D(-) beams for the cooler synchrotron COSY at the IKP of the Forschungszentrum Juelich. Routinely about 8 microA of unpolarized or 1 microA of pola­rized H(-) ions are delivered for charge-exchange injection into COSY. A polarization in excess of 90 % was measured for protons inside the synchrotron COSY. Additionally, polarized and unpolarized D(-) ions have been delivered to experiments. A sequence of up to eight different polarization states for deuterons has been provided for experiments. By advancing the components of the polarized ion the number of polarized particles for injection into the cyclotron has been increased by a factor of three to 5,5x1012 protons, delivered in a 20 ms pulse with a repetition rate of 2 seconds. This report sums up the charac­teristics of the ion sources and the cyclotron in their present mode of opera­tion and de­scribes the achievements towards higher beam intensities as well as for providing unpolarized and polarized H(-) and D(-) beams with high reliability.  
WEPCH072 The High Order Non-linear Beam Dynamics in High Energy Storage Ring of FAIR 2083
 
  • A.N. Chechenin, R. Maier, Y. Senichev, E. Senicheva
    FZJ, Jülich
 
  The High Energy Storage Ring (HESR) is part of the international project FAIR for antiproton physics with beam in the momentum range from 1.5 to 15 GeV/c to explore the research areas of hadron structure and quark-gluon dynamics. An important feature of the project is the combination of phase space cooled beams with thick internal targets. Therefore there are two obvious reasons of beam heating: the target-beam interaction and the intra-beam scattering. Another source of the beam size growth is the higher order resonances. In the paper we investigate the non-linear beam dynamics together with different correction schemes minimizing this effect and compare with other sources of beam heating. Since the tune working point has a spread dependent on the chromaticity correction scheme and space charge, we include in our consideration both effects as well. All beam dynamics calculations are carried out with the SIMBAD code from the Unified Accelerator Library (UAL). We use 10000 macro particles, grid sizes 64x64 and 1000 turns per run.  
WEPCH119 Beam Performance with Internal Targets in the High-energy Storage Ring (HESR) 2197
 
  • A. Lehrach, R. Maier, D. Prasuhn
    FZJ, Jülich
  • O. Boine-Frankenheim, R.W. Hasse
    GSI, Darmstadt
  • F. Hinterberger
    Universität Bonn, Helmholtz-Institut für Strahlen- und Kernphysik, Bonn
 
  The High-energy Storage Ring of the future International Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt is planned as an antiproton synchrotron storage ring in the momentum range of 1.5 to 15 GeV/c. An important feature of HESR is the combination of phase space cooled beams and dense internal targets (e.g., pellet targets), which results in demanding beam parameter requirements for two operation modes: high luminosity mode with peak luminosities of up to 2·1032 cm-2 s-1, and high resolution mode with a momentum spread down to 10-5, respectively. The beam cooling equilibrium and beam loss with internal target interaction is analyzed. Rate equations are used to predict the rms equilibrium beam parameters. The cooling and intra-beam scattering rate coefficients are obtained from simplified models. Energy loss straggling in the target and the associated beam loss are analyzed analytically assuming a thin target. A longitudinal kinetic simulation code is used to study the evolution of the momentum distribution in coasting and bunched beam. The analytic expressions for the target induced momentum tail are found in good agreement with the simulation results.

*A. Lehrach et al. Beam Performance and Luminosity Limitations in the High-Energy Storage Ring (HESR), Nuclear Inst. and Methods in Physics Research, A44704 (2006).

 
THPCH008 The Non-linear Space Charge Field Compensation of the Electron Beam in the High Energy Storage Ring of FAIR 2802
 
  • A.N. Chechenin, R. Maier, Y. Senichev
    FZJ, Jülich
 
  In the High Energy Storage Ring, a part of the FAIR project at GSI in Darmstadt, the internal target is used. To compensate the interaction of the beam with the target, the electron beam cooling is needed. However, together with the cooling, the non-linear space charge field of electron beam modifies the dynamic aperture. We investigate the possible schemes of this effect compensation using the multi-pole correctors on the HESR.