Author: Reeg, H.
Paper Title Page
MOPPR013 Beam Loss and Transmission Control at FAIR 801
  • M. Schwickert, T. Hoffmann, F. Kurian, H. Reeg, A. Reiter
    GSI, Darmstadt, Germany
  • W. Vodel
    HIJ, Jena, Germany
  FAIR, the Facility for Antiproton and Ion Research, is presently entering the final layout phase at GSI. The injector chain consists of the existing linear accelerator UNILAC and synchrotron SIS18, plus a new dedicated 70 MeV high-intensity proton Linac. Along the injector chain to the main synchrotron SIS100 as well as in the beam transport lines, which connect synchrotrons, storage rings and experimental areas, beam transmission or vice versa beam loss have to be controlled very precisely. To supply a maximum intensity of 5·1011 U28+/spill to experiments and to prevent machine damages by intense beams, an integrated system for transmission and loss control is mandatory. While various kinds of beam current transformers control transmission online, intercepting Particle Detector Combinations (scintillators, ionization chambers, secondary electron monitors) are foreseen for optimization runs. External Beam Loss Monitors indirectly detect loss positions by measuring secondary particles. This contribution summarizes the requirements for the related detector systems and presents basic concepts for beam loss and transmission control at FAIR.  
MOPPR020 An Improved Cryogenic Current Comparator for FAIR 822
  • R. Geithner, W. Vodel
    HIJ, Jena, Germany
  • R. Geithner, R. Neubert, P. Seidel
    FSU Jena, Jena, Germany
  • F. Kurian, H. Reeg, M. Schwickert
    GSI, Darmstadt, Germany
  Online monitoring of low intensity (below 1 μA) charged particle beams without disturbing the beam and its environment is crucial for any accelerator facility. For the upcoming FAIR project a beam monitor based on the Cryogenic Current Comparator principle with an enhanced resolution was developed. The main focus of research was on the low temperature properties of the ferromagnetic core material of the superconducting pickup coil. The pickup coil transforms the magnetic field of the beam into a current that is detected by a high performance low temperature dc Superconducting QUantum Interference Device (LTS-DC-SQUID). The penetration of the pickup coil by interfering magnetic fields is highly attenuated by a meander shaped superconducting shielding. The Cryogenic Current Comparator is able to measure DC beam currents, e.g. as required for slow extraction from a synchrotron, as well as bunched beams. In this contribution we present first results of the improved Cryogenic Current Comparator working in a laboratory environment.