High-Frequency Scattering
Journal
Physical Review
Journal Volume
104
Journal Issue
5
Pages
1201-1212
Date Issued
1956
Author(s)
Wu, Tt
Abstract
In recent years, there has been a revival of interest in the phenomena of scattering at high frequencies. The simplest problems of this sort, in which the obstacle is either a circular cylinder or a sphere, are treated here. The treatment is limited to the total scattering cross sections, even though the method is by no means restricted in this way. The specific problems treated here include the scattering of a plane electromagnetic wave by a perfectly conducting circular cylinder (two possible polarizations) or a perfectly conducting sphere, the acoustic scattering by a rigid sphere, and the quantum-mechanical scattering by an impenetrable sphere.By considering the creeping waves as defined on the universal covering space, the scattering cross sections of a circular cylinder may be expressed by asymptotic expansions for vanishingly small wavelengths. Analogous calculations yield the corresponding results for a sphere. It turns out, as expected, that the resulting expressions are accurate even for fairly large wavelengths. The first six terms of the asymptotic series are explicitly found in each case.In conclusion, the application of the method to the determination of the approximate current distribution on the obstacle is considered briefly; also some generalizations about the scattering cross section are conjectured.
SDGs
Type
journal article