Research of cathodes efficiency operation in mode of explosive emission

Pulse linear accelerators on the basis of whose activity lies the phenomenon of an explosive electron emission have the greatest economic benefit due to high efficiency. To the diode constructively placed in a vacuum chamber is applied to a pulse of high voltage and from set of micropoints available on a surface of the cathode there is an autoelectronic emission of intensive electronic flows. The emission currents result in ohmic heating and flash evaporation of micropoints. As a result, the local areas of plasma form on a surface of the cathode. The extension and coalescence of these areas, cathode plumes result in sharp increase of an effective area, from which an emission of electrons occurs. The current emitted from formed plasma, is confined not by area of surface of the cathode (limitation by power of source feed), and space charge of a cloud of particles in an interval between the cathode and anode (limitation by a space charge). This paper discusses three problems of the system: rather low efficiency of electron generation; instability of the characteristic of beams; the nonuniformity of a current density, which is especially expressed in beams of big section. Improvement of these characteristics is discussed