The quality of permanent magnets plays a particularly important role in undulator performance. Many different types of magnet sorting to enhance undulator performance have been carried out at different facilities. Meanwhile, progress in improving magnet quality has been made by different vendors. At the Advanced Photon Source (APS) we have assembled, measured, and analyzed over 14 new undulators of the same mechanical design, some of them with sorted magnets and some unsorted. The performance differences appear to be insignificant in meeting the tight APS Upgrade (APS-U) undulator requirements.
Proceedings of the 12th International Particle Accelerator Conference, IPAC2021, Campinas, SP, Brazil