Overview of intense beam-driven relativistic backward wave oscillators and their use in high power microwave effects studies

Summary form only given. A great deal has been learned regarding the operation of intense relativistic electron beam-driven backward wave oscillators (BWO´s) over the last few years. The issue of pulse shortening seems to be better understood, although its complete remediation has yet to be demonstrated. The energies radiated in X-band have yet to reach the kiloJoule level, although reliable operation at 10´s to 100´s of Joules has been established. In the presentation, we describe recent results obtained on the long pulse BWO using a variety of sophisticated diagnostics. We discuss operation in the cross-excitation regime, and how it can be exploited in high power microwave (HPM) effects studies.