Experiment on the cold test model of a 2-cell superconducting deflecting cavity for ALS at LBNL

Deflecting cavities are proposed for ALS at LBNL to generate sub-picosecond X-ray pulses. A 2-cell structure has been simulated to achieve required deflecting voltage and damping waveguide is attached on beam pipe to get low impedance. To demonstrate the simulation, we made an aluminum cold test model. Detailed configuration of the experiments measuring the field distribution and Qs with/without waveguide loaded are presented. Calculated (R/Q)s and waveguide damping are compared with simulation.