Ionization Phenomena in a Gas-Particle Plasma

Citation

Gibson, Edward George (1964) Ionization Phenomena in a Gas-Particle Plasma. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/B2A5-KH20. https://resolver.caltech.edu/CaltechETD:etd-09182002-091822

Abstract

Several interesting and practically important types of ionization phenomena which occur in a plasma that is composed of thermionically-emitting particles and an ionized gas, have been investigated. There are many interactions that can take place between the particles and the gas which are able to alter the electron density of the plasma appreciably from what it would be in the absence of the particles. Several of these interactions have been explored. Throughout all of the analysis, the emphasis has been placed on gaining a physical understanding of the basic phenomena which are involved. In order to determine the nature of the potential and charge distributions which exist in a gas - particle plasma, the problem in which there is no gaseous ionization and equilibrium prevails has first been thoroughly investigated. Using a family of numerical solutions to Poisson's equation, it has been shown that these distributions can be divided into two characteristic regimes and that a simple algebraic expression, which has been derived, is a good approximation to the potential distribution in one of them. A readily applied method of calculation of the electron density in the plasma and a study of the dependence of this density on the initial parameters which enter the problem have been presented. The relations which are required in order to analyze non-equilibrium ionization phenomena in a gas - particle plasma have been formulated and then applied to various special cases. The case which has received the major emphasis is that in which the particles are hotter than the gas and an enhancement in the gaseous ionization results. It has been shown that this enhancement could be quite large. Electron absorption by the particles, particle quenching of the gaseous ionization, and the supression of either particle or gas ionization, due to the presence of the other, have also been investigated

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