Energy losses from the electron beam in a beam-plasma discharge

The results of experimental study of the dependence of efficiency in longitudinal movement energy ηe and total energy ηΣ of an electron beam, used to produce beam-plasma discharge, on the ωpe/ωH ratio and gun perveance P are presented. It is shown that in the whole tested range ηnp∼ηΣ. At ωpe/ωH=6 and P=6 the efficiency practically reaches saturation. With the ωpe/ωH decrease and at P<6 the efficiency quickly drops. On the basis of the results obtained some critical notes concerning the role of several mechanisms of beam energy transformation, considered theoretically, are formulated