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arXiv · 0905.4845

The soft X-ray polarization in obscured AGN

Stefano Bianchi·Giorgio Matt·Francesco Tamborra·Marco Chiaberge·Matteo Guainazzi·Andrea Marinucci
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Abstract

The soft X-ray emission in obscured active galactic nuclei (AGN) is dominated by emission lines, produced in a gas photoionized by the nuclear continuum and likely spatially coincident with the optical narrow line region (NLR). However, a fraction of the observed soft X-ray flux appears like a featureless power law continuum. If the continuum underlying the soft X-ray emission lines is due to Thomson scattering of the nuclear radiation, it should be very highly polarized. We calculated the expected amount of polarization assuming a simple conical geometry for the NLR, combining these results with the observed fraction of the reflected continuum in bright obscured AGN.

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Stefano Bianchi, Giorgio Matt, Francesco Tamborra, Marco Chiaberge, Matteo Guainazzi, Andrea Marinucci. 2009-05-29. The soft X-ray polarization in obscured AGN. https://doi.org/10.1017/cbo9780511750809.020

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