FEATURES OF THE INTERACTION OF AN ELECTRON-BEAM WITH THE WAVES OF THE CORRUGATED WAVE-GUIDE PARTLY FILLED BY PLASMA

It is shown, that the existence of two waves of E-type (slow and fast) at the same frequency less than the plasma frequency can occure in the system, consisting of the circular waveguide partly filled by magnetized plasma. When the wall of the waveguide is corrugated they can connect each other, constructing a new waves with hybrid properties in a certain range of frequencies. The interac- tion of an electron beam with the hybrid waves differs from that with the slow plasma wave in the smooth wall waveguide and with the wave of the vacuum corrugated waveguide. In particular, when two wa- ves travelling in the same direction are connected, the increments of the hybrid waves have the values of the same order but some less than the increment of a slow plasma wave in the smooth waveguide.