Light scattering by a homogeneous sphere with radial projections

Abstract

Total scattering by a homogeneous sphere with projections is compared with that of the smooth homogeneous sphere of equal total volume and refractive index. The sphere sizes examined are x = 2πa/λ = 0.03 − 1200, n = 1.05. Scattered light from randomly oriented particles is predicted numerically with the Rayleigh-Gans-Debye approximation for small and intermediate particles and with van de Hulst’s anomalous diffraction approximation for intermediate and large ones. The results indicate moderate effects on total scattering of projection (spine) formation at the expense of the particle core. Spine formation does not change scattering by small (Rayleigh) particles; it decreases total scattering when x = 0.1 − 45 more or less in proportion to the total mass of the spines, and it increases scattering for x > 45 by somewhat more.