Comparative research of big size MC & MD cathodes

Summary form only given. For technological applications is necessary to cross section electron beam. For this task the have the high stability of characteristic and durability. A metal ceramic 1 (MC) and metal-dielectric have these characteristics, in many respects, having a uniform beam current density distribution. Experiments with MC and MD cathodes were the URT1M2 repetitive nanosecond electron (accelerating voltage up to 1 MV, FWHM pulse ns, pulse repetition rate up to 50 pps). Besides, were tested up to 300 pps on the accelerator URTFor control of cross section and current distribution electron beam are used cathodes with several plates and metal screen. The electron beam with one-size dimension 400 mm were formed with uniform current that 15% for long time full day (6 hours) operation hours) at 200 pps without cleaning MC and Profound effect of vacuum level on time interval cleaning MC and MD plate was found. Strong influence of the plates geometry on the of vacuum diode with MD cathode and sizes beam cross section was found. The MC cathode had the output beam current bigger that the MD cathode (in the same geometry) that the accelerating voltage was 15% below At the same time the MC plate was 100 expensive in production. Besides MC plates are of a deposit from vacuum oil in the same plates. Therefore a big size MC cathode had the advantage in low ohms and low vacuum diode.