Beam dynamics in wigglers: tracking in PEP with damping wigglers and measurements at SPEAR

Results of tracking with PATRICIA for PEP (Positron-Electron Project) with damping wigglers are presented. Experimental measurements of tune shift with amplitude in a SPEAR wiggler are also included. Tracking with PATRICIA for SPEAR with the rotated sextupole and octupole components included in the 15-period wiggler indicates that the dynamic aperture may be inside the physical aperture.<
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