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Authors
Advisor(s)
Abstract(s)
This work is concerned with devising a method of evaluation of electron emission in the
framework of the Murphy-Good theory, which would be as simple and computationally efficient as
possible while being accurate in the full range of conditions of validity of the theory. The method
relies on Pad e approximants. A comparative study of electron emission from cathodes of arcs in
ambient gas and vacuum arcs is performed with the use of this method. Electron emission from
cathodes of arcs in ambient gas is of thermionic nature even for extremely high gas pressures
characteristic of projection and automotive arc lamps and is adequately described by the
Richardson-Schottky formula. The electron emission from vaporizing (hot) cathodes of vacuum
arcs is of thermo-field nature and is adequately described by the Hantzsche fit formula. Since no
analytical formulas are uniformly valid for field to thermo-field to thermionic emission, a
numerical evaluation of the Murphy-Good formalism is inevitable in cases where a unified
description of the full range of conditions is needed, as is the general case of plasma-cathode
interaction in vacuum arcs, and the technique proposed in this work may be the method of choice
to this end.
Description
Keywords
Electron emission from arc cathodes Thermionic electron emission . Faculdade de Ciências Extas e da Engenharia
Citation
Benilov, M. S., & Benilova, L. G. (2013). Field to thermo-field to thermionic electron emission: a practical guide to evaluation and electron emission from arc cathodes. Journal of Applied Physics, 114(6), 063307.
Publisher
American Institute of Physics