Effect of plasma on efficiency enhancement in a high power relativistic backward wave oscillator

A linear theory of the excitation of electromagnetic waves in a plasma-filled backward-wave oscillator driven by an intense relativistic electron beam is presented. It is found that the spatial growth rate of backward-wave instability exhibits a resonant increase for a particular value of fill-plasma density. Results are compared to the results of an experiment by K. Minami et al. (1988) on a high-power backward-wave oscillator.<
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