Measurements of Smith–Purcell radiation

We present experimental results on Smith–Purcell radiation. Our primary interest was in the measurement of radiation angular distribution, output power, and spectral content. The variations of the angular distribution and the output power were shown for different electron-beam voltages and currents. The output power measured with a 3-mA and 120-kV electron beam was ∼30 μW/cm2-sr. The spectral analysis of the radiation shows excellent agreement between the measurements and the theoretical predictions. Our results were compared with those obtained by Gover et al, [ J. Opt. Soc. Am. B1, 723 ( 1984)].