
Accession Number : AD0645465
Title : THE POWER LAW AND CONSTANT LOSS MODELS IN SECONDARY ELECTRON EMISSION.
Descriptive Note : Physical sciences research papers,
Corporate Author : AIR FORCE CAMBRIDGE RESEARCH LABS L G HANSCOM FIELD MASS
Personal Author(s) : Gianino,Peter D. ; Burke,Edward A.
Report Date : OCT 1966
Pagination or Media Count : 28
Abstract : There is evidence that the lowenergy component of secondary emission from metals under relativistic electron bombardment can be predicted using experimental data obtained under lowenergy irradiation. This greatly enhances the motivation for establishing a model applicable to lowenergy bombardment which can reliably predict the behavior of all necessary quantities. Two phenomenological models  namely, the Power Law (P.L.) and the Constant Loss (C. L.) assumptions  have already been employed in this energy range. This report presents a more comprehensive and conclusive treatment of both assumptions with the ultimate aim of deciding which is the more suitable. It includes, for both suppositions, the derivation of all pertinent equations, including the ratio E/delta x; the furnishing of many more equivalent expressions for the maximum total yield; and the reduction of the equations for total yields at moderately high energies to a form identical with that used successfully at relativistic energies for the lowenergy component from thin targets. When the reduced yields of both models are compared with that of empirical data, results indicate that the P. L. model with n = 1.35 provides a more satisfactory fit. Further examination shows that the parameter A appears to be a fixed constant, not a characteristic of each material, and the total yields and energies in the moderately high range in the P. L. determination of E/delta x are interchangeable with the maximum total yield and its corresponding energy. (Author)
Descriptors : (*SECONDARY EMISSION, *ELECTRONS), ELECTRON IRRADIATION, MODEL THEORY, MATHEMATICAL ANALYSIS
Subject Categories : Electricity and Magnetism
Nuclear Physics & Elementary Particle Physics
Distribution Statement : APPROVED FOR PUBLIC RELEASE