Design, Construction, and Performance of the TPS Accelerator Magnets

This paper presents the design of magnets for the storage ring of the 3-GeV Taiwan Photon Source project. Detailed calculations of the field were performed according to a three-dimensional model, and the magnetic geometry was determined in transverse and longitudinal planes to conform to highly precise magnetic fields. The final tolerances of the pole profiles of the magnets within 20 μm were manufactured and measured in all prototype magnets. The characteristics of the magnetic fields were measured with Hall-probe and rotating-coil systems to verify the quality of the magnetic fields. The centers of the magnets will be aligned on the girder with precisely machined rails within 20 μm, and the magnets have no provision for shimming on the girder. The features of the main field and homogeneity of these magnets are described and analysed to reveal the satisfactory magnetic performance.