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X-Ray Scattering by Nonspherical Grains. I. Oblate Spheroids

B. T. Draine·Khosrow Allaf-Akbari
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Abstract

We calculate the scattering of X-rays by interstellar dust, for a dust model that reproduces the observed wavelength-dependent extinction and polarization of starlight. On interstellar sightlines that produce appreciable starlight polarization, we predict that the dust-scattered X-ray halo around point sources will have measurable azimuthal asymmetry due to scattering by partially-aligned nonspherical grains. We calculate the expected halo asymmetry. X-ray halo asymmetry provides a new test of interstellar dust models.

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B. T. Draine, Khosrow Allaf-Akbari. 2006-08-01. X-Ray Scattering by Nonspherical Grains. I. Oblate Spheroids. https://doi.org/10.1086/508133

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