Generation and Formation of Axially Symmetrical Tubular Electron Beam in a Cold Metal Secondary-Emission Cathode Magnetron Gun—Part II: Computer Modeling

Abstract

This paper presents the computer modeling results, explaining the generation mechanism of periodical electron bunches in a cold cathode metal secondary-emission magnetron gun and describes a scenario of the secondary-emission electron multiplication at the front and droop portions of the anode voltage pulse. An analytical model for analyzing the kinematical characteristics of the formed electron cloud and a self-consistent numerical mathematical model on the basis of the particle-in-cell method for studying the collective electron processes have been developed. The general stages of forming the electron beam in the cold cathode secondary-emission magnetron gun are shown. It is shown that an efficiency of secondary-electron multiplication depends on the shape and parameters of the high-voltage pulse. The obtained results of the computer modeling are in good agreement with the experimental data.Index Terms-Cold metal cathode, computer modeling, crossed-field gun, field emission, secondary-electron emission, tubular electron beam.

Vacuum Microwave Sources of Electromagnetic Radiation

“…In order to improve the magnetron operation, there conducted active investigations of new effective cathode materials and cathode node constructions, providing high durability and emission stability. It especially concerns investigations connected with applying the cold secondaryemission cathodes providing virtually instant readiness and nonfilament ("cold") start of magnetrons [22,[24][25][26][27][28].…”

“…The state-of-the-art evolution of magnetrons is associated with increasing the frequency (phase) stability and rising the lifetime, as well as enhancing reliability due to an application of the cold cathodes [21,24,[26][27][28]. In particular, there is a significant interest in the development of magnetrons in the millimeter range.…”