CESR-C: A wiggler-dominated collider

CESR-c operates with twelve 2.1 tesla wigglers that account for 90% of the synchrotron radiation with beam energy in the range of 1.8 to 2.1 GeV. The wigglers reduce the radiation damping time from 0.5 seconds to 50 milliseconds. The carefully designed wigglers restrict neither physical nor dynamic aperture of the storage ring though both quadrupole and sextupole distributions must be tailored to compensate the primary optics effects of the wigglers. Colliding beam performance limits are determined by the numerous parasitic beam-beam interactions in the single ring. Several approaches taken to mitigate these limiting effects are described herein. The CESR-c wigglers are an excellent match to the requirements for future damping rings. Flexible optics, extensive infrastructure, and resource expertise, form an effective test bed for assessment and solution of damping ring issues such as electron cloud and ion effects, and exploring ultra-low emittance beams.