Hollow-cathode electron source with a fast gas valve

摘要

In this paper the parameters of a hollow-cathode electron source and generated electron beam are presented. A gas-puff valve is used to provide a sharp pressure gradient between the cathode cavity and the accelerating gap. Parameters of a He gas and the plasma inside the cathode and the accelerating gap studied by electrical and optical diagnostics for different gas pressure and an amplitude of the discharge current are presented. It was found that the operation of the HC is characterized by a negative anode potential fall and that the plasma density and temperature do not exceed 5/spl times/10/sup 12/ cm/sup -3/ and 14 eV, respectively. Parameters of the electron beam for different discharge current and anode grid cell sizes are presented. It was shown that efficient electron beam generation with an amplitude of the beam current up to 300 A does not lead to significant increase of the plasma potential. The results of the simulation of the HC operation agree with the obtained data.