Characterization of beam dynamics in the APS injector rings using time-resolved imaging techniques

Images taken with streak cameras and gated intensified cameras with both time (longitudinal) and spatial (transverse) resolution reveal a wealth of information about circular accelerators. We illustrate a novel technique by a sequence of dual-sweep streak camera images taken at a high dispersion location in the booster synchrotron, where the horizontal coordinate is strongly correlated with the particle energy and the "top-view" of the beam gives a good approximation to the particle density distribution in the longitudinal phase space. A sequence of top-view images taken right after injection clearly shows the beam dynamics in the phase space. We report another example from the positron accumulator ring for the characterization of its beam compression bunching with the 12th harmonic rf.