Impact of superbends at the ALS

To satisfy a demand for more high energy, high brightness X-ray sources at the Advanced Light Source (ALS), a plan is in place to replace three 1.3 Tesla normal conducting bending magnets with three 5 Tesla superconducting magnets (superbends) in the year 2001. In this paper we discuss the impact of the superbends on the ALS beam parameters and particle dynamics. In particular we show the effect on the emittance, energy spread, and lifetime. We find that by adjusting the dispersion to be positive in the straight section we are able to largely restore the horizontal emittance. The vertical emittance can be adjusted independently to control the lifetime. The particle dynamics are investigated through particle tracking with a frequency analysis postprocessor. We find that by placing the three superbends symmetrically around the ring there is ample dynamic aperture for injection and lifetime