An apparatus based on a plasma emitter for electron-beam transportation to air

Abstract

An apparatus for electron-beam transportation to air has been developed on the basis of an electron gun with a plasma emitter. A pressure drop from values of (1–3) × 10⁻⁴ Torr in an accelerating gap to an air pressure of 760 Torr is produced by the differential pumping system. Usually, no less than three pumping stages are used in apparatuses based on hot-cathode guns for electron-beam transportation to air because of the need to maintain the pressure in the hot-cathode area at a level of 10⁻⁵ Torr. It is possible to simplify the differential pumping system by reducing the number of stages to two via to the use of a gun with a plasma emitter. The construction of an apparatus for electron-beam transportation to air is described and its key characteristics are presented.