Operation of a relativistic backward wave oscillator filled with a pre-ionized, high density, radially inhomogeneous plasma

Summary form only given. A modified relativistic (500 kV, 500 A) backward wave oscillator filled with radially non-uniform, pre-ionized plasma of high peak density (peak plasma frequency>operating frequency) is studied experimentally. The effects of high plasma density in the interaction region as well as the relativistic diode and the output horn regions were studied. By protecting both the diode and output regions against plasma penetration, the plasma effects on the BWO was studied up to a peak plasma density >10/sup 13/ cm/sup -3/.