Atomic and Ionic Impact Phenomena on Metal Surfaces

Atomic and Ionic Impact Phenomena on Metal Surfaces

Author: M. Kaminsky

Publisher: Springer Science & Business Media

Published: 2013-03-08

Total Pages: 414

ISBN-13: 3642460259

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The collisions of neutral or charged gaseous particles with solid surfaces govern many physical and chemical phenomena, as has been The gas/solid phenomena in turn depend on a recognized for a long time. great variety of processes such as the charge transfer of the gas/solid interface, adsorption and desorption, the energy transfer between an incident particle and the surface, etc. Our knowledge of these processes, however, is only fragmentary. This is partly due to the difficulty in adequately controlling the ex perimental conditions. Consequently, until recently the data were usually so complex that reliable information about a particular elementary process could not be deduced. Within the last five to ten years, however, the techniques of ultra-high vacuum and surface preparation have developed rapidly and there has been a booming and widespread interest in the role of gas/solid interactions in such diverse fields as plasma physics, thermonuclear reactions, thermionic energy conversion, ion propulsion, sputtering corrosion of the surface of satellites and ion engines, ion getter pumps, deposition of thin films, etc. This led to extensive investigations of numerous gas/solid phenomena, such as surface ionization, sputtering, emission of secondary electrons and ions from surfaces under atom and/or ion impact, ion neutralization, and the thermal accomodation of gaseous particles on surfaces. As a result, it has become possible to gather a variety of valuable information.


Atoms and Their Spectroscopic Properties

Atoms and Their Spectroscopic Properties

Author: V.P. Shevelko

Publisher: Springer Science & Business Media

Published: 2013-03-14

Total Pages: 212

ISBN-13: 3662034344

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Atoms and Their Spectroscopic Properties has been designed as a reference on atomic constants and elementary processes involving atoms. The topics include energy levels, Lamb shifts, electric multipole polarizabilities, oscillator strengths, transition probabilites, and charge transfer cross sections. In addition the subjects of ionization, photoionization, and excitation are discussed. The book also comprises a large number of figures and tables, with ample references. Simple analytical formulas allow one to estimate the atomic characteristics without resorting to a computer.


Electron Impact Ionization

Electron Impact Ionization

Author: T.D. Märk

Publisher: Springer Science & Business Media

Published: 2013-06-29

Total Pages: 395

ISBN-13: 3709140285

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It is perhaps surprising that a process which was one of the first to be studied on an atomic scale, and a process which first received attention over seven decades ago, continues to be the object of diverse and intense research efforts. Such is the case with the (seemingly) conceptually simple and familiar mechanism of electron impact ionization of atoms, molecules, and ions. Not only has the multi-body nature of the collision given ground to theoretical effort only grudgingly, but also the variety and subtlety of processes contributing to ionization have helped insure that progress has come only with commensurate work: no pain - no gain. Modern experimental methods have made it possible to effectively measure and explore threshold laws, differential cross sections, partial cross sections, inner-shell ionization, and the ionization of unstable species such as radicals and ions. In most instances the availability of experimental data has provided impetus and guidance for further theoretical progress.


Theory of Non-equilibrium Ionization in Wet Alkali Metal Vapors, Continuous Changing Model

Theory of Non-equilibrium Ionization in Wet Alkali Metal Vapors, Continuous Changing Model

Author: John Milton Smith

Publisher:

Published: 1964

Total Pages: 32

ISBN-13:

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A theory for non-equilibrium ionization in wet alkali metal vapor is formulated. The media is considered to consist of electrons, neutral gas atoms, positively charged atomic ions, and charged vapor droplets. The degree of ionization of the gas atoms is assumed to be given by Saha's Law evaluated at the electron temperature while the degree of charging of the vapor droplets is obtained by equating the random electron current in the gas to the thermionic emission current of the vapor droplet at its internal temperature. The electron temperature is determined by equating the Joule heating rate of the electrons to their rate of energy loss due to elastic electron-atom, electron-ion, and electron-droplet collisions and inelastic electron-droplet collisions. The droplet internal temperature is determined by equating the rate of droplet heating due to electron bombardment to the rate of cooling due to atom and ion bombardment. The above theory is applied to MHD generator considerations for which the predominate effect of the droplets is found to be the absorption of free electrons from the system accompanied by an increase in magnetic field requirements. The depression of electron density is found to be most severe at high percent moisture and for small droplets. (Author).