Strong Submillimeter Radiation from Intense Relativistic Electron Beams

Radiation from an intense relativistic electron beam at submillirneter wavelengths has been measured with bandpass and high-pass filters. Radiated power ~100 kW has been measured in the passband 390-540 mu m. The generation of this radiation depends on giving the electrons a large energy component transverse to the magnetic field. Coherent wave generation mechanisms which may account for the observed radiation are discussed.