BPM and orbit correction systems at the Duke storage ring

Stable and reliable storage ring operation critically depends on the orbit stability. At Duke, an orbit stability program is well under way to achieve the high level of orbit performance necessary for reliable free electron laser (FEL) and gamma-ray operation. Progress has been made to reduce the current dependency of BPM readings via choice of cables and band-pass filters. Beam based alignment has been carried out to accurately determine the locations of quadrupole centers. A global orbit correction system and a slow orbit feedback system have been developed. Integrated with operation, these systems have demonstrated the ability to significantly improve the overall storage ring performance.