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arXiv · 2207.03228

Investigating the X-ray polarization of lamp-post coronae in BHXRB

Wenda Zhang·Michal Dovčiak·Michal Bursa·Vladimír Karas·Giorgio Matt·Francesco Ursini
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Abstract

High-sensitivity X-ray polarimetric observations of black hole X-ray binaries, which will soon become available with the launches of space-borne X-ray observatories with sensitive X-ray polarimeters, will be able to put independent constraints on the black hole as well as the accretion flow, and possibly break degeneracies that cannot be resolved by spectral/timing observations alone. In this work we perform a series of general relativistic Monte-Carlo radiative transfer simulations to study the expected polarization properties of X-ray radiation emerging from lamp-post coronae in black hole X-ray binaries. We find that the polarization degree of the coronal emission of black hole X-ray binaries is sensitive to the spin of the black hole, the height of the corona, and the dynamics of the corona.

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Wenda Zhang, Michal Dovčiak, Michal Bursa, Vladimír Karas, Giorgio Matt, Francesco Ursini. 2022-07-07. Investigating the X-ray polarization of lamp-post coronae in BHXRB. https://doi.org/10.1093/mnras%2Fstac1937

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