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arXiv · 2311.12851

Extension of Radiative Transfer Coherent Backscattering RT-CB code to dense discrete random media

Johannes Markkanen·Antti Penttilä
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Abstract

The Radiative transfer coherent backscattering (RT-CB) code is extended to apply to dense discrete random media of optically soft spherical particles. This is achieved by utilizing the well-known static-structure-factor (SSF) correction derived from the Percus-Yevick approximation for sticky-hard-sphere (SHS) pair correlation function. The code is verified against the numerically exact electromagnetic method for small spherical media consisting of submicrometer-sized icy particles at optical wavelengths. The SSF-corrected RT-CB method significantly improves solution accuracy, and the solution agrees well with the numerically exact solution when the packing density is less than 20% and particles are optically soft, i.e., the refractive index of particles is close to that of the background medium.

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Johannes Markkanen, Antti Penttilä. 2023-10-20. Extension of Radiative Transfer Coherent Backscattering RT-CB code to dense discrete random media. https://doi.org/10.1016/j.jqsrt.2023.108733

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