Planar electromagnetic multipole correctors for a circularly polarized undulator

Abstract

Planar electromagnetic correction lenses were designed, constructed, and installed in order to compensate skew multipole components generated by an electromagnetic circularly polarizing undulator (CPU) for the Advanced Photon Source (APS). The reason for selection of the planar configuration is that the corrector lenses should fit around a flat undulator vacuum chamber. Comparison was made between the measured strength of skew multipole components and results calculated by the 3D code RADIA [1].