Injection Beam Dynamics in Spear3

1 SLAC National Accelerator Laboratory, Menlo Park, CA 94025 2 Brookhaven National Laboratory, Upton, NY 11973 3 Life Imaging Technology, Palo Alto, CA 94301 Abstract For the top-off operation it is important to understand the time evolution of charge injected into the storage ring. The large-amplitude horizontal oscillation quickly filaments and decoheres, and in some cases exhibits nonlinear x-y coupling before damping to the stored orbit. Similarly, in the longitudinal dimension, any mismatch in beam arrival time, beam energy or phase-space results in damped, non-linear synchrotron oscillations. In this paper we report on measurements of injection beam dynamics in the transverse and longitudinal planes using turn-by-turn BPMs, a fast-gated, image-intensified CCD camera and a Hamamatsu C5680 streak camera.