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Fast Ionized X-Ray Absorbers in AGNsWe investigate the physics of the X-ray ionized absorbers often identified as warm absorbers (WAs) and ultra-fast outflows (UFOs) in Seyfert AGNs from spectroscopic studies in the context of magnetically-driven accretion-disk wind scenario. Launched and accelerated by the action of a global magnetic field anchored to an underlying accretion disk around a black hole, outflowing plasma is irradiated and ionized by an AGN radiation field characterized by its spectral energy density (SED). By numerically solving the Grad-Shafranov equation in the magnetohydrodynamic (MHD) framework, the physical property of the magnetized disk-wind is determined by a wind parameter set, which is then incorporated into radiative transfer calculations with xstar photoionization code under heating-cooling equilibrium state to compute the absorber's properties such as column density N(sub H), line-of-sight (LoS) velocity v, ionization parameter xi, among others. Assuming that the wind density scales as n varies as r(exp. -1), we calculate theoretical absorption measure distribution (AMD) for various ions seen in AGNs as well as line spectra especially for the Fe K alpha absorption feature by focusing on a bright quasar PG 1211+143 as a case study and show the model's plausibility. In this note we demonstrate that the proposed MHD-driven disk-wind scenario is not only consistent with the observed X-ray data, but also help better constrain the underlying nature of the AGN environment in a close proximity to a central engine.
Document ID
20170003563
Acquisition Source
Goddard Space Flight Center
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Fukumura, K.
(James Madison Univ. Harrisonburg, VA, United States)
Tombesi, F.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Kazanas, D.
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Shrader, C.
(Maryland Univ. Baltimore County Baltimore, MD, United States)
Behar, E.
(Technion Research and Development Foundation Ltd. Haifa, Israel)
Contopoulos, I.
(Academy of Athens Greece)
Date Acquired
April 17, 2017
Publication Date
May 2, 2016
Publication Information
Publication: Astronomische Nachrichten
Publisher: Wiley
Volume: 337
Issue: 5-Apr
ISSN: 0004-6337
e-ISSN: 1521-3994
Subject Category
Astrophysics
Numerical Analysis
Report/Patent Number
GSFC-E-DAA-TN41646
Funding Number(s)
CONTRACT_GRANT: NNG06EO90A
CONTRACT_GRANT: NNG17PT01A
Distribution Limits
Public
Copyright
Other
Keywords
accretion
magnetohydrodynamics
accretion disks; numerical; Seyfert;

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