Microwave Analog to the Scattering of Light by Nonspherical Particles

Abstract

A microwave technique has been developed for obtaining total cross sections and angular distributions for the scattering of electromagnetic radiation by nonspherical particles whose size is of the order of the wavelength. The scattering by spheroidal and cylindrical refracting particles has been measured for three orthogonal orientations of the symmetry axis. Comparison of the results with exact and approximate theoretical calculations for spheres, spheroids, and finite and infinite cylinders indicates the possibility of developing useful approximation methods. Some interesting effects have been noted, particularly a very large resonance in the scattering by finite cylinders. The results have been given preliminary application to the problem of the nature of the interstellar material which absorbs and polarizes starlight.