CAUSES OF MICROWAVE GENERATION DISRUPTION IN VACUUM RELATIVISTIC MICROWAVE GENERATORS

This work is devoted to the problem of microwave radiation disruption in generators using high-current relativistic electron beams (REB). Th e experiments were carried out with a 500-keV, 3-kA, 1-mu s REB. Optic al, X-ray, and other diagnostics were employed. We were careful to eli minate any influence of the cathode, diaphragm, or collector plasma up on the microwave generator. The observed premature cut-off of the micr owave radiation was shown to be caused by a microwave breakdown occurr ing inside the generator slow-wave system. This breakdown was initiate d as a result of the slow-wave system wall being bombarded with electr ons, both the main-REB primary or the collector-backscattered ones. A method of preventing plasma formation in the slow-wave system is propo sed.