A Study of the Effect of Beam-Beam Interactions on CESR Optics

The CESR storage ring facility has begun operation in an energy region which allows high-statistics investigation of charm-quark bound states. Experience during the first two years has shown that the effects of parasitic crossings in the pretzel orbits present an important factor in injection efficiency, in the beam lifetime and in the stored current limits. We compare the results of beam dynamics and tracking calculations which quantify the effects of these parasitic crossings on optics and dynamic aperture for the injected and stored trajectories to observations of beam behavior.