Initial time-resolved particle beam profile measurements at the Advanced Photon Source

The commissioning of the 7-GeV Advanced Photon Source (APS) storage ring began in early 1995. Characterization of the stored particle beam properties involved time-resolved transverse and longitudinal profile measurements using optical synchrotron radiation (OSR) monitors. Early results include the observation of the beam on a single turn, measurements of the transverse beam sizes after damping using a 100 μs integration time (σx∼150±25 μm, σy∼65±25 μm, depending on vertical coupling), and measurement of the bunch length (στ∼25 to 55 ps, depending on the charge per bunch). The results are consistent with specifications and predictions based on the 8.2 nm-rad natural emittance, the calculated lattice parameters, and vertical coupling less than 10%. The novel, single-element focusing mirror for the photon transport line and the dual-sweep streak camera techniques, which allow turn-by-turn measurements, will also be presented. The latter measurements are believed to be the first of their kind on a storage ring in the USA. copyright 1996 American Institute of Physics