Author: Béchu, N.
Paper Title Page
THPC149 Development of PrFeB Cryogenic Undulator (CPMU) at SOLEIL 3233
 
  • C. Benabderrahmane, P. Berteaud, N. Béchu, L. Chapuis, M.-E. Couprie, J.P. Daguerre, J.-M. Filhol, C. Herbeaux, A. Lestrade, M. Louvet, J.L. Marlats, K. Tavakoli, M. Valléau, D. Zerbib
    SOLEIL, Gif-sur-Yvette, France
 
  A R&D programme for the construction of a 2 m long 18 mm period CPMU is under progress at SOLEIL. The cryogenic undulator will provide photons in the region of 1.4 to 30 keV. It will be installed in the next few months on the long straight section (SDL13) of the storage ring, and could be used later on to produce photons for the NANOSCOPIUM beamline. The use of PrFeB which features a 1.35 T remanence (Br) at room temperature enables to increase the peak magnetic field at 5.5 mm minimum gap, from 1.04 T at room temperature to 1.15 T at a cryogenic temperature of 77 K. Praseodymium was chosen instead of Neodymium magnetic material, because it is more resistant against the appearance of the Spin Reorientation Transition. Different corrections were performed first at room temperature to adjust the phase error, the electron trajectory and to reduce the multipolar components. The mounting inside the vacuum chamber enables the fitting of a dedicated magnetic measurement bench to check the magnetic performance of the undulator at low temperature. The results of the magnetic measurements at low temperature and the comparison with the measurement at room temperature are reported.