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Active Galaxy Unification in the Era of X-Ray PolarimetryActive galactic nuclei (AGNs), Seyfert galaxies, and quasars are powered by luminous accretion and often accompanied by winds that are powerful enough to affect the AGN mass budget, and whose observational appearance bears an imprint of processes that are happening within the central parsec around the black hole (BH). One example of such a wind is the partially ionized gas responsible for X-ray and UV absorption (warm absorbers). Here, we show that such gas will have a distinct signature when viewed in polarized X-rays. Observations of such polarization can test models for the geometry of the flow and the gas responsible for launching and collimating it. We present calculations that show that the polarization depends on the hydrodynamics of the flow, the quantum mechanics of resonance-line scattering, and the transfer of polarized X-ray light in the highly ionized moving gas. The results emphasize the three-dimensional nature of the wind for modeling spectra. We show that the polarization in the 0.1-10 keV energy range is dominated by the effects of resonance lines. We predict a 5%-25% X-ray polarization signature of type-2 objects in this energy range. These results are generalized to flows that originate from a cold torus-like structure, located approximately 1 pc from the BH, which wraps the BH and is ultimately responsible for the apparent dichotomy between type 1 and type 2 AGNs. Such signals will be detectable by future dedicated X-ray polarimetry space missions, such as the NASA Gravity and Extreme Magnetism Small Explorer SMEX, "GEMS" Swank et al. (2008).
Document ID
20100014805
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
Dorodnitsyn, A.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Kallman, T.
(NASA Goddard Space Flight Center Greenbelt, MD, United States)
Date Acquired
August 24, 2013
Publication Date
January 1, 2010
Subject Category
Astrophysics
Meeting Information
Meeting: High-resolution X-ray Spectroscopy: Past, Present and Future
Location: Utrecht
Country: Netherlands
Start Date: March 15, 2010
End Date: March 17, 2010
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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