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Polarization of resonance X-ray lines from clusters of galaxies

S. Sazonov·E. Churazov·R. Sunyaev
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Abstract

As is known, resonant scattering can distort the surface-brightness profiles of clusters of galaxies in X-ray lines. We demonstrate that the scattered line emission should be polarized and possibly detectable with near-future X-ray polarimeters. Spectrally-resolved mapping of a galaxy cluster in polarized X-rays could provide valuable independent information on the physical conditions, in particular element abundances and the characteristic velocity of small-scale turbulent motions, in the intracluster gas. The expected degree of polarization is of the order of 10% for richest regular clusters (e.g. Coma) and clusters whose X-ray emission is dominated by a central cooling flow (e.g. Perseus or M87/Virgo).

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S. Sazonov, E. Churazov, R. Sunyaev. 2001-12-17. Polarization of resonance X-ray lines from clusters of galaxies. https://doi.org/10.1046/j.1365-8711.2002.05390.x

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