Light Scattering by Spheroidal Particles Oriented by Streaming

Formulas are given for the intensity of light scattered by spheroidal particles which are partially oriented by streaming, as in a concentric cylinder apparatus. The calculation uses a general theory of scattering which is based on an expansion in inverse powers of the wavelength and the theory of streaming alignment developed by Peterlin and Stuart and numerically evaluated by Scheraga, Edsall, and Gadd. Different polarizations of the incident wave are taken into account. Numerical calculations have been made for a number of values of the relevant parameters, the results of which are illustrated by a series of graphs. The results should be accurate to within at least 5% if the ratio $\mathrm{[(\pi \hspace{0.17em}\times \hspace{0.17em}}\mathrm{longest\; dimension}\mathrm{)/}\mathrm{wavelength}]$ does not exceed 0.8 and the relative refractive index does not exceed 1.20.