A beamline design and data acquisition with the 20-MeV, 20-ps electron beam for the higher-order mode studies of the APS SR-RF cavities

A beamline has been designed and assembled to use the ANL Chemistry Division 20-MeV electron linac for the testing of higher-order mode excitation and damping in RF cavities. The beamline consists of two sections (a beam collimating section with a 1.5"-OD vacuum line, and a cavity test section with a 3"-OD vacuum line), separated by two double aluminum foil windows. The beam diagnostics consist of a stripline beam position monitor, integrating current transformers, fluorescent screens, and a Faraday cup. EPICS (Experimental Physics and Industrial Control System) is used for beamline control, monitoring and data acquisition. Also described is the diagnostic system used for beam image capture and analysis using EPICS-controlled hardware and PV-WAVE software. The RF cavity measurement will be described in a separate paper. >