Scattering of a Laser Beam by High-Temperature Plasmas

The time-average intensity of electromagnetic radiation scattered by a 50-kV electron beam from a $Q$-switched laser beam, incident at 90° and polarized with $\overrightarrow{E}$ perpendicular to the electron beam, is measured as a function of angle with respect to the electron beam. The measured values agree with those calculated using a model that corrects for the fact that the scattering electrons pass through the scattering region during the period of observation. This correction is important in the measurement of plasma distribution functions by laser scattering for plasmas with electron temperatures greater than 10 keV.