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We present a study of X-ray ionization of magnetohydrodynamic (MHD) accretion-disk winds in an effort to constrain the physics underlying the highly-ionized ultra-fast outflows (UFOs) inferred by X-ray absorbers often detected in various sub-classes of Seyfert active galactic nuclei (AGNs). Our primary focus is to show that magnetically-driven outflows are indeed physically plausible candidates for the observed outflows accounting for the AGN absorption properties of the present X-ray spectroscopic observations. Employing a stratified MHD wind launched across the entire AGN accretion disk, we calculate its X-ray ionization and the ensuing X-ray absorption line spectra. Assuming an appropriate ionizing AGN spectrum, we apply our MHD winds to model the absorption features in an {it XMM-Newton}/EPIC spectrum of the narrow-line Seyfert, pg. We find, through identifying the detected features with Fe K$alpha$ transitions, that the absorber has a characteristic ionization parameter of $log (xi_c [erg~cm~s$^{-1}$]) simeq 5-6$ and a column density on the order of $N_H simeq 10^{23}$ cm$^{-2}$, outflowing at a characteristic velocity of $v_c/c simeq 0.1-0.2$ (where $c$ is the speed of light). The best-fit model favors its radial location at $r_c simeq 200 R_o$ ($R_o$ is the black hole innermost stable circular orbit), with an inner wind truncation radius at $R_{rm t} simeq 30 R_o$. The overall K-shell feature in the data is suggested to be dominated by fexxv with very little contribution from fexxvi and weakly-ionized iron, which is in a good agreement with a series of earlier analysis of the UFOs in various AGNs including pg.
Blueshifted absorption lines in the X-ray spectra of AGN show that ultra-fast outflows with typical velocities $v sim 0.1c$ are a common feature of these luminous objects. Such powerful AGN winds offer an explanation of the observed M-$sigma$ relatio
Among a number of active galactic nuclei (AGNs) that drive ionized outflows in X-rays, a low-redshift (z = 0.184) quasar, PDS 456, is long known to exhibit one of the exemplary ultra-fast outflows (UFOs). However, the physical process of acceleration
We explore the poloidal structure of two-dimensional (2D) MHD winds in relation to their potential association with the X-ray warm absorbers (WAs) and the highly-ionized ultra-fast outflows (UFOs) in AGN, in a single unifying approach. We present the
We observed the quasar PG1211+143 using the Cosmic Origins Spectrograph on the Hubble Space Telescope in April 2015 as part of a joint campaign with the Chandra X-ray Observatory and the Jansky Very Large Array. Our ultraviolet spectra cover the wave
We use MUSE adaptive optics (AO) data in Narrow Field Mode to study the properties of the ionised gas in MR 2251-178 and PG 1126-041, two nearby (z~0.06) bright quasars hosting sub-pc scale Ultra Fast Outflows (UFOs) detected in the X-ray band. We de