Rf and beam diagnostic instrumentation at the Advanced Photon Source (APS) linear accelerator (Linac)

A system of beam diagnostics and rf phase and amplitude measurement, based mostly on VXI, was implemented at the APS Linac and has now operated successfully for more than two years. Standardization of instrumentation among the various APS accelerators accounted for some of the non-VXI packaged equipment that was used. Equipment for which the optimum topology or location did not lend itself to VXI was also accommodated so as to yield the greatest stability, reliability, and flexibility. The APS Linac instrumentation is described, and operational performance is discussed. Future plans, including an expansion to include a switchable spare klystron (which can be accommodated with only minor changes to the VXI-housed equipment) and a beam position monitor using frequency domain analysis to provide improved determination of positron position in a mixed-particle beam condition are also discussed.