Electron beam excitation of potential oscillations in a plasma narrow waveguide with a metal screen

Monoenergetic low-density electron beam excitation of potential surface oscillation in a plasma cylindrical waveguide with a metal screen is examined. The beam either coincides with plasma or flows it around. Plasma is placed in the external magnetic field. Wave dispersion and decay were found when the beam is absent. The increments of increase are determined for the excited wave band. It is shown that the metal screen placed at a definite distance from plasma can essentially change surface oscillation dispersion, increments and instability conditions