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arXiv · 0801.1406

Modelling interstellar extinction and polarization with spheroidal grains

N. V. Voshchinnikov·H. K. Das
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Abstract

We calculate the wavelength dependence of the ratio of the linear polarization degree to extinction (polarizing efficiency) $P(λ)/A(λ)$ from the ultraviolet to near-infrared. The prolate and oblate particles with aspect ratios from $a/b=1.1$ up to 10 are assumed to be rotating and partially aligned with the mechanism of paramagnetic relaxation (Davis--Greenstein). Size/shape/orientation effects are analyzed. It is found that the wavelength dependence of $P(λ)/A(λ)$ is mainly determined by the particle composition and size whereas the values of $P(λ)/A(λ)$ depend on the particle shape, degree and direction of alignment.

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N. V. Voshchinnikov, H. K. Das. 2008-01-09. Modelling interstellar extinction and polarization with spheroidal grains. https://doi.org/10.1016/j.jqsrt.2008.01.003

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