Author: Harder, D.A.
Paper Title Page
MOPPP089 Development of a PrFeB Cryogenic Undulator at NSLS-II 762
  • C.A. Kitegi, P. Cappadoro, O.V. Chubar, T.M. Corwin, H.C. Fernandes, D.A. Harder, P. He, G. Rakowsky, J. Rank, C. Rhein, T. Tanabe
    BNL, Upton, Long Island, New York, USA
  Recent cryogenic undulators use Praseodymium-Iron-Boron (PrFeB) magnets cooled down to 80K. The main drawn drawback of the PrFeB magnet grades developed so far are their relative low coercive field at ambient temperature, below 2 T which prevents PrFeB based cryogenic undulator from baking. Some precautions are required during the undulator assembling and shimming to ensure ultra high vacuum compatibility. However Hitachi Metal Industry (HMI) recently developed two different grades of PrFeB magnet with large coercive field but at the expense of the remanent field. The magnetization curves have been measured from 40 K up to 400 K to determine the field increase and to investigate the magnet withstanding to baking. An IVU prototype has also been baked. Magnetic measurements before and after baking are also presented.