Spectral properties of stimulated Raman radiation from an intense relativistic electron beam

Spectra have been obtained in the range of wavelengths from 1–3 mm for the stimulated Raman scattering from an intense relativistic electron beam which propagates in a rippled magnetostatic field (’’zero frequency pump’’). The Raman scattering from the plasma space charge wave and the cyclotron wave idler modes has been observed and the frequency dependence upon beam energy, rippled period, and guiding magnetic field is found to be in accord with theory. Results suggest that the spectral linewidth for the scattered radiation is influenced by beam energy spread and the amplitude of the rippled field pump.