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NASA NTRS · 20160012558

Electromagnetic Scattering by Fully Ordered and Quasi-Random Rigid Particulate Samples

Mishchenko, Michael I.·Dlugach, Janna M.·Mackowski, Daniel W.
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Abstract

In this paper we have analyzed circumstances under which a rigid particulate sample can behave optically as a true discrete random medium consisting of particles randomly moving relative to each other during measurement. To this end, we applied the numerically exact superposition T-matrix method to model far-field scattering characteristics of fully ordered and quasi-randomly arranged rigid multiparticle groups in fixed and random orientations. We have shown that, in and of itself, averaging optical observables over movements of a rigid sample as a whole is insufficient unless it is combined with a quasi-random arrangement of the constituent particles in the sample. Otherwise, certain scattering effects typical of discrete random media (including some manifestations of coherent backscattering) may not be accurately replicated.

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Radiative transferSpeckleRandom mediaPariclesT-matrix methodPolarizationElectomagnetic scattering

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Mishchenko, Michael I., Dlugach, Janna M., Mackowski, Daniel W.. 2016-10-10. Electromagnetic Scattering by Fully Ordered and Quasi-Random Rigid Particulate Samples. https://ntrs.nasa.gov/citations/20160012558

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