Author: Baecker, H.-J.     [Bäcker, H.-J.]
Paper Title Page
WEPWA003 Hall-Probe Bench for Cryogenic in-Vacuum-Undulators 2126
  • C. Kuhn, H.-J. Bäcker, J. Bahrdt, A. Gaupp, B. Schulz
    HZB, Berlin, Germany
  The Helmholtz-Zentrum Berlin (HZB) builds a 2m long in-vacuum-hall-probe-bench for the characterization of several cryogenic undulators currently under development. Short period lengths and small gaps require an accurate correlation between Hall probe position / orientation and the 3D-magnetic field. The geometric tolerances of an in-vacuum bench in the presence of strong temperature gradients do not permit a Hall probe movement along a straight line without corrections. The HZB-bench employs a system of laser interferometers and position sensitive detectors, which is used in a feed-back loop for the Hall probe position / orientation. First measurements on the accuracy and reproducibility of the new device are presented.