PERMANENT MAGNETS ACCELERATORS AND ENGINEERING DIVISION The layout of the magnetic structure of the upgrade machine requires SYNCHROTRON SOLEIL HIGHLIGHTS 2020 a total of about 1000 magnets with demanding specifications and a compact structure. The magnets should then be very compact, provide very large strength and operate at low cost. In consequence, permanent magnet (PM) technology is preferred over electromagnet technology, Corresponding authors when it is possible. All the combined-function dipoles, reverse bends Amor Nadji & Laurent S. Nadolski and more than 70% of the quadrupoles are so far planned to be in Synchrotron SOLEIL, PM. The prototyping stage is essential to study the sensitivity of the L’Orme des Merisiers, Saint-Aubin, PM to temperature variation, the risk of demagnetization, complexity BP48, 91192 Gif-sur-Yvette Cedex, for adjustment and the quality of the magnetic field. All the permanent France. magnets use Samarium-Cobalt (Sm2Co17) magnets with a conservative amor.nadji@synchrotron-soleil.fr strength (coercive field of 850 kA/m and remanent field of 1.12 T) as it laurent.nadolski@synchrotron-soleil.fr exhibits strong resistance to radiation damage and a small temperature Captions coefficient (below -0.04%/K). A first PM prototype has already been built: Figure 3 shows a PM quadrupole. Preliminary magnetic measurements FIGURE 1: Sorption capacity tests for NEG-coated using the single stretched wire technique are promising. chambers of DN38/DN20/DN10 mm inner diameter. The 3 curves represent the evolution of the ratio between the upstream pressure P1 and the downstream pressure P2 FIGURE 3 with the number of injected molecules of CO2. FIGURE 2: Photo Stimulated Desorption beamline using the photon beam produced by the 1.71 T dipole source D08-1 with its first test chamber (diameter 63 mm) to qualify the experimental setup. FIGURE 3: PM quadrupole prototype for the upgrade (top) and comparison with a typical electromagnetic quadrupole (bottom) in the present machine. 97