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For collision of an ion with a metal surface, with reference to aerodynamic applications, the report examines the general problem of the physical mechanisms of the accompanying processes and the specific problem of the charge states of the gas particle and surface. The semi-empiric Hagstrum theory is discussed with correction of its internal contradictions. It is considered firmly established that ion neutralization by given metallic surfaces corresponds to the mechanism of Auger neutralization. The theory discussed permits calculation of aerodynamic values with good accuracy. It is found that practically all positive ions that collide with a pure metallic surface are neutralized. Secondary electrons must be taken into account in calculation of the charge state. A considerable part of the energy of ion neutralization and the energy of strongly excited atoms is converted to thermal energy, which can exceed ion kinetic energy at a velocity of about 8 km/sec. (Author), Unedited rough draft trans. of Aerodinamika Razreshennykh Gazov (USSR) n3 p110-123 1967.

Results are given of (1) a study of the cone formation which arises at the surface of a high sputtering yield target such as Cu when it is seeded during sputtering with another material such as Mo, and (2) the analysis of composition changes at the surface of multicomponent targets under ion bombardment and of sputter deposited films by means of in situ auger electron analysis. (Author)

Research effort was concentrated to employ high resolution lithium drifted germanium detectors in an effort to obtain high precision measurements of atomic fluorescence yields. This portion of the research was accomplished successfully. Other efforts to investigate ways of using Auger electron spectroscopy to enhance knowledge of atomic fluorescence yields were not achieved. The report describes the research techniques used in the two areas. (Author)

A theory of the ejection of electrons from atomically clean metals by slow ions of the noble gases arising from Auger transitions is presented. Scattering matrix elements are evaluated from first principles and the secondary ejected electron energy distribution and total yield are found. The approach used in the solution of this problem is that of the quantum theory of scattering. This approach eliminates determining transition matrix elements per unit time as a function of the distance of the ion from the metal surface, and will allow the direct calculation of the secondary electron energy distribution, total yield, spatial distribution, position of most probable neutralization, and depth of origination of Auger electrons. The formal solution is applied to the situation of He(+) ions of low energy incident on atomically clean tungsten. Normal incidence is treated although the theory is not restricted to this case. Typical theoretical curves are presented and compared with the experimental results of others. A discussion of such effects as energy broadening, effective ionization energy, uncertainty principle effects, inelastic electron scattering, and density of electron states in metals is included. (Author)

A soft x-ray appearance potential spectrometer (SXAPS) has been assembled, tested, and used to record spectra of selected materials for the purpose of studying the feasibility of routine elemental and chemical characterization of surfaces. These initial results demonstrate capabilities of SXAPS as a surface analysis tool and provide guidelines for the development of a more sensitive detection system for the technique. Characteristics of the SXAP spectrometer and criteria for the development of a detection system with an improved dynamic range of sensitivity are presented. (Author)