Multipole Errors and Methods of Correction for TPS Lattice Magnets

Abstract

Taiwan Photon Source (TPS) is a synchrotron radiation facility of medium energy, 3 GeV, and low emittance, under construction at National Synchrotron Radiation Research Center (NSRRC). The multipole errors of lattice magnets were rigorously examined and corrected so as to maintain the dynamic aperture of the electron beam in the storage ring. The lattice magnets were fully inspected at both the vendor and vendee sites. The multipole errors of the lattice magnets were tested and corrected. In particular, the sextupole magnets have the pole position adjusted to correct the multipole errors so as to conform to the specification. The yoke cutting is to correct the octupole error of the long-quadrupole magnets. The shimming of the magnetic center and the final examination of the magnets will be undertaken at NSRRC. In this paper, we report the methods of correcting the multipole errors, the magnetic center, and the performance of the TPS lattice magnets.

Development of Type A Quadrupole Magnet for Siam Photon Source II

“…The multipole fields are analyzed based on multipole field expansion as expressed in Equation (3) instead. The multipole coefficients B n of the type A quadrupole magnet obtained from the so-called fitting method [25] are summarized in Table 2 for the applied current of 99 A. 3) instead.…”

“…3) instead. The multipole coefficients Bn of the type A quadrupole magnet obtained from the so-called fitting method [25] are summarized in Table 2 for the applied current of 99 A. Open symbols represent the magnetic field calculated using Opera-3D.…”