A high-power electron beam source based on the superemissive cathode

Abstract

A robust, high current electron beam, produced by emission from a refractory metal cathode operating in the superemissive mode, is reported. Electron beam current of ≳150 A is produced by a back-lighted thyratron during the conductive phase. Electron energies are several hundred eV and the electron beam has the duration of the discharge pulse. A simple differential pumping scheme has been used to demonstrate extraction of the electron beam into a low pressure (<7 mTorr) region.