Effect of ion-plasma oscillations on the amplitude characteristics of long-interaction devices

The appearance of static regular components of the noise spectrum was studied for the self-excitation of an O-type BWT with premodulation of the electron beam by a microwave signal. The collector potential is found to play a double role in variations of ion density in the interaction space: it controls longitudinal ion drift and changes the ion concentration by changing the number of slow secondary electrons. The development of ion-plasma oscillations is explained by a two-beam mechanism for the interaction of secondary electrons and ions.