Light Scattering by Aggregates with Sizes Comparable to the Wavelength: An Application to Cometary Dust

Cometary dust is likely to have aggregate structure. Therefore the optical properties of aggregates must be understood if one wants to obtain information on cometary dust from optical observations. In this paper the scattering properties of polydisperse clusters with sizes comparable to the visible wavelengths are studied. It is shown that the sizes of the constituent monomers play a vital role in establishing the phase functions of intensity and linear polarization. Irregularly structured aggregates composed of a moderate number of touching spheres (