Coherent radiation at submillimeter and millimeter wavelengths

The paper describes the experimental results on coherent synchrotron radiation (SR), coherent Cherenkov radiation (CR) and coherent transition radiation (TR) at submillimeter and millimeter wavelengths. Coherent radiation intensities vs. He gas pressure are shown at /spl lambda/=500 nm and 4 mm. Angular distributions of coherent CR and/or coherent TR were obtained in vacuum and at atmospheric pressure. Coherent TR spectra at different emission lengths were obtained at /spl lambda/=0.2/spl sim/5 mm.<
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