Beam Stability at the Advanced Photon Source

The Advanced Photon Source has been in operation since 1996. Since that time, extensive incremental improvements to orbit stabilization systems have been made. This includes the addition of 80 channels of narrowband rf beam position monitors (BPMs), 44 channels of bending magnet photon BPMs, and most recently the inclusion of 16 insertion device photon BPMs into the orbit correction response matrix. In addition, considerable improvements have been made in the area of power supply regulation, both for the main multipole magnets and the steering corrector magnets. The present status of overall performance will be discussed, including long-term pointing stability, reproducibility, and AC beam motion.