Author: Geithner, R.
Paper Title Page
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.