High-current electron beam microwave excitation in plasma-filled corrugated coaxial waveguide

The interaction of electron beam with plasma-filled corrugated coaxial waveguide is investigated. The dispersion equation describing the interaction of beam with such. hybrid slow-wave structure is obtained. The properties of eigen waves of structure are studied analytically and numerically. The unstable oscillations growth rate and its dependencies on plasma density, beam current and energy are determined. It is shown that for nonrelativistic electron beams the maximal growth rate of instability for plasma-filled slow-wave structure exceed essentially the vacuum structure instability growth rate.