Generation of a coherent Cherenkov radiation by using electron bunch tilting

We have been developing a compact accelerator based on a laser photocathode rf electron gun at Waseda University. Low emittance and short bunched electron beam can be generated from the gun. Also, the rf transverse deflecting cavity was developed for the bunch length measurement. We performed an experiment for generating a coherent Cherenkov radiation using bunch tilting. The rf transverse deflector can give a tilt for the electron bunch, and the tilt angle was set to the Cherenkov radiating angle which determined by the target refractive index. We successfully demonstrated a coherent Cherenkov radiation and the characterization of the radiation. The principle of coherent Cherenkov radiation generation, the experimental results and future prospective will be presented at the conference.