• F.-Y. Lin, C.-H. Chang, H.-H. Chen, J.C. Huang, M.-H. Huang, C.-S. Hwang, J.C. Jan, C.Y. Kuo, C.-S. Yang
  NSRRC, Hsinchu

Taiwan Photon Source (TPS) is a new third generation synchrotron storage ring with energy 3 GeV, which consists of 24 double-bend cells and its circumference is 518.4 m. Various accelerator lattice magnets which consist of 48 bending magnets, 240 quadrupoles and 168 multifunction sextupole magnets. All magnets pole profiles, edge shim and magnet end chamfer were designed in TOSCA and RADIA magnetic computation code. In order to verify the magnetic field quality of computation code, prototype magnets have been manufactured in this year. Two measurement systems, hall probe and rotating coils, were used for magnetic field mapping. This paper presents magnetic field mapping results of prototype magnets and compared with original magnetic circuit designs.

• J.C. Jan, C.-H. Chang, C.-S. Hwang, F.-Y. Lin
  NSRRC, Hsinchu

A magnet array of superconducting undulator SU15, with 130 poles and length 0.98 m, was constructed, and the field measurement and training are also performed at National Synchrotron Radiation Research Center (NSRRC). The NbTi wires were excited to 1.36 T @ 497 A after 28 times quench. A cryogenic Hall probe (length 2500 mm) was used to characterize the distribution of the magnetic field of magnet arrays in the 5.6-mm magnetic gap. The measurement region of the cryogenic Hall probe is greater than 1200 mm in the vertical dewar. The length shrinkage or expansion of the Hall probe depends on the thermal variation at both ends of the Hall probe. The length of the Hall probe will be evaluated in the field measurement region. The reproducibility of the measurement system was verified in the same experiment. A field shimming method involving a trim iron piece was used to correct for deviations of the magnetic field. This paper discusses the measurement accuracy in the cryogenic Hall probe system and presents results of the field shimming.