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We present the first resolved imaging of the milliarcsecond-scale jets in the neutron star X-ray binary Circinus X-1, made using the Australian Long Baseline Array. The angular extent of the resolved jets is ~20 milliarcseconds, corresponding to a physical scale of ~150 au at the assumed distance of 7.8 kpc. The jet position angle is relatively consistent with previous arcsecond-scale imaging with the Australia Telescope Compact Array. The radio emission is symmetric about the peak, and is unresolved along the minor axis, constraining the opening angle to be less than 20 degrees. We observe evidence for outward motion of the components between the two halves of the observation. Constraints on the proper motion of the radio-emitting components suggest that they are only mildly relativistic, although we cannot definitively rule out the presence of the unseen, ultra-relativistic (Lorentz factor >15) flow previously inferred to exist in this system.

We present new Chandra images of the X-ray emission from the core of the Perseus cluster of galaxies. The total observation time is now 1.4 Ms. New depressions in X-ray surface brightness are discovered to the north of NGC1275, which we interpret as old rising bubbles. They imply that bubbles are long-lived and do not readily breakup when rising in the hot cluster atmosphere. The existence of a 300 kpc long NNW-SSW bubble axis means there cannot be significant transverse large scale flows exceeding 100 km/s. Interesting spatial correlations are seen along that axis in early deep radio maps. A semi-circular cold front about 100 kpc west of the nucleus is seen. It separates an inner disturbed region dominated by the activity of the active nucleus of NGC1275 from the outer region where a subcluster merger dominates.

We present the spectral analysis of three Suzaku XIS observations of 3C 111 requested to monitor the predicted variability of its ultra-fast outflow on ~7 days time-scales. We detect an ionized iron emission line in the first observation and a blue-shifted absorption line in the second, when the flux is ~30% higher. The location of the material is constrained at

A fraction of active galactic nuclei (AGN) exhibit dramatic variability, which is observed on timescales down to minutes in the X-ray band. We introduce the case study of 1H 1934-063 (z = 0.0102), a Narrow-line Seyfert 1 (NLS1) among the brightest and most variable AGN ever observed with XMM-Newton. This work includes spectral and temporal analyses of a concurrent XMM-Newton and NuSTAR 2015 observation lasting 130 kiloseconds, during which the X-ray source exhibited a steep (factor of 6) plummet and subsequent full recovery of flux level, accompanied by deviation from a single log-normal flux distribution. We rule out Compton-thin obscuration as the cause for this dramatic variability observed even at NuSTAR energies. In order to constrain coronal geometry, dynamics, and emission/absorption processes, we compare detailed spectral fitting with Fourier-based timing analysis. Similar to other well-studied, highly variable Seyfert 1s, this AGN is X-ray bright and displays strong reflection features. We find a narrower broad iron line component compared to most Seyfert 1s, and constrain black hole spin to be < 0.1, one of the lowest yet discovered for such systems. Combined spectral and timing results are consistent with a dramatic change in the continuum on timescales as short as a few kiloseconds dictating the nature of this variability. We also discover a Fe-K time lag, measuring a delay of 20 seconds between relativistically-blurred reflection off the inner accretion flow and the hard X-ray continuum emission., 13 pages, 11 figures, Accepted to ApJ

Multi-epoch X-ray spectroscopy (0.3-25 keV) of the Seyfert 1.2 galaxy Mrk 79 (UGC 3973) spanning nearly eight years and a factor of three in broadband flux are analysed. The data are obtained at seven epochs with either XMM-Newton or Suzaku. Comparison with contemporaneous RXTE monitoring indicate that all flux states of Mrk 79 are represented by the data. The spectra are fitted in a self-consistent manner adopting a power law and ionised reflection to describe the broadband continuum. Modification of the spectra by a distant photoionised medium, seen predominantly in emission, are also included. Under the assumption that the inner disk is at the innermost stable circular orbit, our blurred reflection models give a spin of a = 0.7+/-0.1. The reflection component in each spectrum is weaker than predicted by simple reflection models. If the illuminating X-ray emission is produced by flares above the disk that move at mildly relativistic velocities, however, diminished reflection is expected. Light bending due to strong gravity near black holes can influence how the illuminating and reflected flux are observed; variations in Mrk 79 do not suggest that light bending is important in this source.

We present an extended scheme for the calculation of the profiles of emission lines from accretion discs around rotating black holes. The scheme includes discs with angular momenta which are parallel and antiparallel with respect to the black hole's angular momentum, as both configurations are assumed to be stable. We discuss line shapes for such discs and present a code for modelling observational data with this scheme in X-ray data analysis programs. Based on a Green's function approach, an arbitrary radius dependence of the disc emissivity and arbitrary limb-darkening laws can be easily taken into account, while the amount of pre-computed data is significantly reduced with respect to other available models.

We investigate the role of host galaxy classification and black hole mass in a heterogeneous sample of 276 mostly nearby (z 99% confidence. Using ring morphology of the host galaxy as a proxy for lack of tidal interaction, we find that AGN luminosity in host galaxies within 70Mpc is independent of host galaxy interaction for $\sim$ Gyrs, suggesting that the timescale of AGN activity due to secular evolution is much shorter than that due to tidal interactions. We find that LINER hosts have lower 12um luminosity than the median 12um luminosity of normal disk- and bulge-dominated galaxies which may represent observational evidence for past epochs of feedback that supressed star formation in LINER host galaxies. We propose that nuclear ULXs may account for the X-ray emission from LINER 2s without flat-spectrum, compact radio cores. We confirmed the robustness of our results in X-rays by comparing them with the 14-195keV 22-month BAT survey of AGN, which is all-sky and unbiased by photoelectric absorption.

We investigate the role of AGN feedback in turbulent heating of galaxy clusters. Specifically, we analyze the production of turbulence by g-modes generated by the supersonic expansion and buoyant rise of AGN-driven bubbles. Previous work which neglects magnetic fields has shown that this process is inefficient, with less than 1% of the injected energy ending up in turbulence. This inefficiency is primarily due to the fact that the bubbles are shredded apart by hydrodynamic instabilities before they can excite sufficiently strong g-modes. Using a plane-parallel model of the ICM and 3D ideal MHD simulations, we examine the role of a large-scale magnetic field which is able to drape around these rising bubbles, preserving them from hydrodynamic instabilities. We find that, while magnetic draping appears better able to preserve AGN-driven bubbles, the driving of g-modes and the resulting production of turbulence is still inefficient. The magnetic tension force prevents g-modes from transitioning into the nonlinear regime, suppressing turbulence in our model ICM. Our work highlights the ways in which ideal MHD is an insufficient description for the cluster feedback process, and we discuss future work such as the inclusion of anisotropic viscosity as a means of simulating high $\beta$ plasma kinetic effects. These results suggest the hypothesis that other mechanisms of heating the ICM plasma such as sound waves or cosmic rays may be responsible for observed feedback in galaxy clusters., Comment: 14 pages, 10 figures, Accepted for publication in The Astrophysical Journal

We analyze a suite of global magnetohydrodynamic (MHD) accretion disk simulations in order to determine whether scaling laws for turbulence driven by the magnetorotational instability, discovered via local shearing box studies, are globally robust. The simulations model geometrically-thin disks with zero net magnetic flux and no explicit resistivity or viscosity. We show that the local Maxwell stress is correlated with the self-generated local vertical magnetic field in a manner that is similar to that found in local simulations. Moreover, local patches of vertical field are strong enough to stimulate and control the strength of angular momentum transport across much of the disk. We demonstrate the importance of magnetic linkages (through the low-density corona) between different regions of the disk in determining the local field, and suggest a new convergence requirement for global simulations -- the vertical extent of the corona must be fully captured and resolved. Finally, we examine the temporal convergence of the average stress, and show that an initial long-term secular drift in the local flux-stress relation dies away on a time scale that is consistent with turbulent mixing of the initial magnetic field., Comment: 8 Pages, 7 Figures ApJ, In Press

We present new and archival Chandra X-ray Observatory observations of -shaped radio galaxies (XRGs) within z ~ 0.1 alongside a comparison sample of normal double-lobed FR I and II radio galaxies. By fitting elliptical distributions to the observed diffuse hot X-ray emitting atmospheres (either the interstellar or intragroup medium), we find that the ellipticity and the position angle of the hot gas follow that of the stellar light distribution for radio galaxy hosts in general. Moreover, compared to the control sample, we find a strong tendency for -shaped morphology to be associated with wings directed along the minor axis of the hot gas distribution. Taken at face value, this result favors the hydrodynamic backflow models for the formation of XRGs which naturally explain the geometry; the merger-induced rapid reorientation models make no obvious prediction about orientation.

We perform a suite of simulations of cooling cores in clusters of galaxies in order to investigate the effect of the recently discovered heat flux buoyancy instability (HBI) on the evolution of cores. Our models follow the three-dimensional magnetohydrodynamics of cooling cluster cores and capture the effects of anisotropic heat conduction along the lines of magnetic field, but do not account for the cosmological setting of clusters or the presence of active galactic nuclei (AGNs). Our model clusters can be divided into three groups according to their final thermodynamical state: catastrophically collapsing cores, isothermal cores, and an intermediate group whose final state is determined by the initial configuration of magnetic field. Modeled cores that are reminiscent of real cluster cores show evolution toward thermal collapse on a timescale which is prolonged by a factor of ∼2-10 compared with the zero-conduction cases. The principal effect of the HBI is to re-orient field lines to be perpendicular to the temperature gradient. Once the field has been wrapped up onto spherical surfaces surrounding the core, the core is insulated from further conductive heating (with the effective thermal conduction suppressed to less than 10-2 of the Spitzer value) and proceeds to collapse. We speculate that, in real clusters, the central AGN and possibly mergers play the role of "stirrers," periodically disrupting the azimuthal field structure and allowing thermal conduction to sporadically heat the core. © 2009. The American Astronomical Society. All rights reserved..

We present a uniform X-ray spectral analysis of eight type-1 active galactic nuclei (AGN) that have been previously observed with relativistically broadened iron emission lines. Utilizing data from the XMM-Newton European Photon Imaging Camera (EPIC-pn) we carefully model the spectral continuum, taking complex intrinsic absorption and emission into account. We then proceed to model the broad Fe K feature in each source with two different accretion disk emission line codes, as well as a self-consistent, ionized accretion disk spectrum convolved with relativistic smearing from the inner disk. Comparing the results, we show that relativistic blurring of the disk emission is required to explain the spectrum in most sources, even when one models the full reflection spectrum from the photoionized disk.

Accretion disk reflection spectra, including broad iron emission lines, bear the imprints of the strong Doppler shifts and gravitational red-shifts close to black holes. The extremity of these shifts depends on the proximity of the innermost stable circular orbit to the black hole, and that orbit is determined by the black hole spin parameter. Modeling relativistic spectral features, then, gives a means of estimating black hole spin. We report on the results of fits made to archival X-ray spectra of stellar-mass black holes and black hole candidates, selected for strong disk reflection features. Following recent work, these spectra were fit with reflection models and disk continuum emission models (where required) in which black hole spin is a free parameter. Although our results must be regarded as preliminary, we find evidence for a broad range of black hole spin parameters in our sample. The black holes with the most relativistic radio jets are found to have high spin parameters, though jets are observed in a black hole with a low spin parameter. For those sources with constrained binary system parameters, we examine the distribution of spin parameters versus black hole mass, binary mass ratio, and orbital period. We discuss the results within the context of black hole creation events, relativistic jet production, and efforts to probe the innermost relativistic regime around black holes., Accepted for publication in ApJ

We present Chandra detections of x-ray emission from the AGN in two giant Low Surface Brightness (LSB) galaxies, UGC 2936 and UGC 1455. Their x-ray luminosities are 1.8\times10^{42} ergs/s and 1.1\times10^{40} ergs/s respectively. Of the two galaxies, UGC 2936 is radio loud. Together with another LSB galaxy UGC 6614 (XMM archival data) both appear to lie above the X-ray-Radio fundamental plane and their AGN have black hole masses that are low compared to similar galaxies lying on the correlation. However, the bulges in these galaxies are well developed and we detect diffuse x-ray emission from four of the eight galaxies in our sample. Our results suggest that the bulges of giant LSB galaxies evolve independently of their halo dominated disks which are low in star formation and disk dynamics. The centers follow an evolutionary path similar to that of bulge dominated normal galaxies on the Hubble Sequence but the LSB disks remain unevolved. Thus the bulge and disk evolution are decoupled and so whatever star formation processes produced the bulges did not affect the disks., Comment: 17 pages, 1 table, 4 figures. To appear in ApJ

We examine the evolution and influence of viscosity-induced diskoseismic modes in simulated black hole accretion disks. Understanding the origin and behavior of such oscillations will help us to evaluate their potential role in producing astronomically observed high-frequency quasi-periodic oscillations in accreting black hole binary systems. Our simulated disks are geometrically-thin with a constant half-thickness of five percent the radius of the innermost stable circular orbit. A pseudo-Newtonian potential reproduces the relevant effects of general relativity, and an alpha-model viscosity achieves angular momentum transport and the coupling of orthogonal velocity components in an otherwise ideal hydrodynamic numerical treatment. We find that our simulated viscous disks characteristically develop and maintain trapped global mode oscillations with properties similar to those expected of trapped g-modes and inner p-modes in a narrow range of frequencies just below the maximum radial epicyclic frequency. Although the modes are driven in the inner portion of the disk, they generate waves that propagate at the trapped mode frequencies out to larger disk radii. This finding is contrasted with the results of global magnetohydrodynamic disk simulations, in which such oscillations are not easily identified. Such examples underscore fundamental physical differences between accretion systems driven by the magneto-rotational instability and those for which alpha viscosity serves as a proxy for the physical processes that drive accretion, and we explore potential approaches to the search for diskoseismic modes in full magnetohydrodynamic disks., Comment: 14 pages, 10 figures. Accepted for publication in The Astrophysical Journal

We report the results from our analysis of {\it Suzaku} XIS (0.5-10 keV) and HXD/PIN (15-40 keV) observations of five well-known local ULIRGs: {\em IRAS} F05189-2524, {\em IRAS} F08572+3915, Mrk 273, PKS 1345+12, and Arp 220. The XIS observations of F05189-2524 and Mrk 273 reveal strong iron lines consistent with Fe K$\alpha$ and changes in spectral shapes with respect to previous {\it Chandra} and {\it XMM-Newton} observations. Mrk 273 is also detected by the HXD/PIN at $\sim$1.8-$\sigma$. For F05189-2524, modeling of the data from the different epochs suggests that the change in spectral shape is likely due to the central source switching off, leaving behind a residual reflection spectrum, or an increase in the absorbing column. An increase in the covering fraction of the absorber can describe the spectral variations seen in Mrk 273, although a reduction in the intrinsic AGN luminosity cannot be formally ruled out. The {\it Suzaku} spectra of Mrk 273 are well fit by a ~94% covering fraction model with a column density of $\sim10^{24}$ cm$^{-2}$. The absorption-corrected log[$L_{\rm 2-10 keV}$ / $L_{\rm IR}$] ratio is consistent with those found in PG Quasars. The 0.5-10 keV spectrum of PKS 1345+12 and Arp 220 seem unchanged from previous observations and their hard X-ray emission is not convincingly detected by the HXD/PIN. The large column density derived from CO observations and the large equivalent width of an ionized Fe line in Arp 220 can be reconciled by an ionized reflection model. F08572+3915 is undetected in both the XIS and HXD/PIN, but the analysis of unpublished {\em Chandra} data provides a new measurement at low energies., Comment: 37 pages including 4 tables and 10 figures. Accepted for publication in ApJ. It is tentatively scheduled to appear in the January 20, 2009 issue of ApJ

We report on simultaneous Chandra/HETGS and RXTE observations of the transient stellar-mass black hole GRO J1655-40, made during its 2005 outburst. Chandra reveals a line-rich X-ray absorption spectrum consistent with a disk wind. Prior modeling of the spectrum suggested that the wind may be magnetically driven, potentially providing insights into the nature of disk accretion onto black holes. In this paper, we present results obtained with new models for this spectrum, generated using three independent photoionization codes: XSTAR, Cloudy, and our own code. Fits to the spectrum in particular narrow wavelength ranges, in evenly spaced wavelength slices, and across a broad wavelength band all strongly prefer a combination of high density, high ionization, and small inner radius. Indeed, the results obtained from all three codes require a wind that originates more than 10 times closer to the black hole and carrying a mass flux that is on the order of 1000 times higher than predicted by thermal driving models. If seminal work on thermally-driven disk winds is robust, magnetic forces may play a role in driving the disk wind in GRO J1655-40. However, even these modeling efforts must be regarded as crude given the complexity of the spectra. We discuss these results in the context of accretion flows in black holes and other compact objects., Many color figures. Accepted for publication in ApJ

We present the results of a uniform analysis of the soft X-ray spectra of fifteen type I AGN observed with the high resolution X-ray gratings on board Chandra. We found that ten of the fifteen AGN exhibit signatures of an intrinsic ionized absorber. The absorbers are photoionized and outflowing, with velocities in the range � 10 1 10 3 km s 1 . The column density of the warm absorbing gas is � 10 20 23 cm 2 . Nine of the ten AGN exhibiting warm absorption are best–fit by multiple ionization components and three of the ten AGN require multiple kinematic components. The warm absorbing gas in our AGN sample has a wide range of ionization parameter, spanning roughly four orders of magnitude (ξ � 10 0 4 ergs cm s 1 ) in total, and often spanning three orders of magnitude in the same gas. Warm absorber components with ionization parameter ξ < 10 generate an unresolved transition array due to Fe in seven of the ten AGN exhibiting warm absorption. These low ionization state absorbers may also carry away the largest mass outflows from the AGN. The mass outflow rate depends critically on the volume filling factor of the gas, which cannot yet be directly measured. However, upper limits on the mass outflow rates for filling factors of unity can be much greater than the expected accretion rate onto the central supermassive black hole and filling factors as small as 1% can give outflow rates comparable to the accretion rate. There appears to be a gap in the outflow velocities in our sample between � 300 500 km s 1 , the origin of which is not clear. The outflow components with velocities below this gap tend to be associated with lower column densities than those with with velocities above the gap.

Local spacetime geometry is not the only thing that black holes affect. They also profoundly influence galaxy formation and have an impact on scales as large as clusters of galaxies.

Recent numerical relativistic simulations of black hole coalescence suggest that in certain alignments the emission of gravitational radiation can produce a kick of several thousand kilometers per second. This exceeds galactic escape speeds, hence unless there a mechanism to prevent this, one would expect many galaxies that had merged to be without a central black hole. Here we show that in most galactic mergers, torques from accreting gas suffice to align the orbit and spins of both black holes with the large-scale gas flow. Such a configuration has a maximum kick speed, referee's comments included, to appear in ApJL

(abridged) In this paper, we examined XMM Newton EPIC spectra of 14 ultra-luminous X-ray sources (ULXs)in addition to the XMM RGS spectra of two sources (Holmberg II X-1 and Holmberg IX X-1). We determined oxygen and iron abundances of the host galaxy's interstellar medium (ISM) using K-shell (O) and L-shell (Fe) X-ray photo-ionization edges towards these ULXs. We found that the oxygen abundances closely matched recent solar abundances for all of our sources, implying that ULXs live in similar local environments despite the wide range of galaxy host properties. Also, we compare the X-ray hydrogen column densities (n_H) for 8 ULX sources with column densities obtained from radio H I observations. The X-ray model n_H values are in good agreement with the H I n_H values, implying that the hydrogen absorption towards the ULXs is not local to the source (with the exception of the source M81 XMM1). In order to obtain the column density and abundance values, we fit the X-ray spectra of the ULXs with a combined power law and one of several accretion disk models. We tested the abundances obtained from the XSPEC models bbody, diskbb, grad, and diskpn along with a power law, finding that the abundances were independent of the thermal model used. We comment on the physical implications of these different model fits. We also note that very deep observations allow a breaking of the degeneracy noted by Stobbart et al. (2006) favoring a high mass solution for the absorbed grad + power law model.

Our current understanding of the curved space-time around supermassive black holes is based on actively accreting black holes, which make up only ten per cent or less of the overall population. X-ray observations of that small fraction reveal strong gravitational redshifts that indicate that many of these black holes are rapidly rotating; however, selection biases suggest that these results are not necessarily reflective of the majority of black holes in the Universe. Tidal disruption events, where a star orbiting an otherwise dormant black hole gets tidally shredded and accreted onto the black hole, can provide a short, unbiased glimpse at the space-time around the other ninety per cent of black holes. Observations of tidal disruptions have hitherto revealed the formation of an accretion disk and the onset of an accretion-powered jet, but have failed to reveal emission from the inner accretion flow, which enables the measurement of black hole spin. Here we report observations of reverberation arising from gravitationally redshifted iron K photons reflected off the inner accretion flow in the tidal disruption event Swift J1644+57. From the reverberation timescale, we estimate the mass of the black hole to be a few million solar masses, suggesting an accretion rate of 100 times the Eddington limit or more. The detection of reverberation from the relativistic depths of this rare super-Eddington event demonstrates that the X-rays do not arise from the relativistically moving regions of a jet, as previously thought., Comment: Published in the 22 June 2016 issue of Nature

We present the results from a joint Suzaku/NuSTAR broad-band spectral analysis of 3C 390.3. The high quality data enables us to clearly separate the primary continuum from the reprocessed components allowing us to detect a high energy spectral cut-off ($E_\text{cut}=117_{-14}^{+18}$ keV), and to place constraints on the Comptonization parameters of the primary continuum for the first time. The hard over soft compactness is 69$_{-24}^{+124}$ and the optical depth 4.1$_{-3.6}^{+0.5}$, this leads to an electron temperature of $30_{-8}^{+32}$ keV. Expanding our study of the Comptonization spectrum to the optical/UV by studying the simultaneous Swift-UVOT data, we find indications that the compactness of the corona allows only a small fraction of the total UV/optical flux to be Comptonized. Our analysis of the reprocessed emission show that 3C 390.3 only has a small amount of reflection (R~0.3), and of that the vast majority is from distant neutral matter. However we also discover a soft X-ray excess in the source, which can be described by a weak ionized reflection component from the inner parts of the accretion disk. In addition to the backscattered emission, we also detect the highly ionized iron emission lines Fe XXV and Fe XXVI., Comment: accepted for publication in ApJ

Central jetted active galactic nuclei (AGN) appear to heat the core regions of the intracluster medium (ICM) in cooling-core galaxy clusters and groups, thereby preventing a cooling catastrophe. However, the physical mechanism(s) by which the directed flow of kinetic energy is thermalized throughout the ICM core remains unclear. We examine one widely discussed mechanism whereby the AGN induces subsonic turbulence in the ambient medium, the dissipation of which provides the ICM heat source. Through controlled inviscid 3-d hydrodynamic simulations, we verify that explosive AGN-like events can launch gravity waves (g-modes) into the ambient ICM which in turn decay to volume-filling turbulence. In our model, however, this process is found to be inefficient, with less than 1% of the energy injected by the AGN activity actually ending up in the turbulence of the ambient ICM. This efficiency is an order of magnitude or more too small to explain the observations of AGN-feedback in galaxy clusters and groups with short central cooling times. Atmospheres in which the g-modes are strongly trapped/confined have an even lower efficiency since, in these models, excitation of turbulence relies on the g-modes' ability to escape from the center of the cluster into the bulk ICM. Our results suggest that, if AGN-induced turbulence is indeed the mechanism by which the AGN heats the ICM core, its driving may rely on physics beyond that captured in our ideal hydrodynamic model., 11 pages. Accepted for publication in The Astrophysical Journal

We present an analysis of the 3–79 keV NuSTAR spectrum of the low-luminosity active galactic nucleus NGC 7213. In agreement with past observations, we find a lower limit to the high-energy cut-off of E_c > 140 keV, no evidence for a Compton-reflected continuum and the presence of an iron K α complex, possibly produced in the broad-line region. From the application of the MYTORUS model, we find that the line-emitting material is consistent with the absence of a significant Compton reflection if arising from a Compton-thin torus of gas with a column density of 5.0^(+2.0)_(−1.6) × 10^(23) cm^(−2). We report variability of the equivalent width of the iron lines on the time-scale of years using archival observations from XMM–Newton, Chandra and Suzaku. This analysis suggests a possible contribution from dusty gas. A fit with a Comptonization model indicates the presence of a hot corona with a temperature kT_e > 40 keV and an optical depth τ ≲ 1, assuming a spherical geometry.

Powerful winds driven by active galactic nuclei (AGN) are often invoked to play a fundamental role in the evolution of both supermassive black holes (SMBHs) and their host galaxies, quenching star formation and explaining the tight SMBH-galaxy relations. Recent observations of large-scale molecular outflows in ultra-luminous infrared galaxies (ULIRGs) have provided the evidence to support these studies, as they directly trace the gas out of which stars form. Theoretical models suggest an origin of these outflows as energy-conserving flows driven by fast AGN accretion disk winds. Previous claims of a connection between large-scale molecular outflows and AGN activity in ULIRGs were incomplete because they were lacking the detection of the putative inner wind. Conversely, studies of powerful AGN accretion disk winds to date have focused only on X-ray observations of local Seyferts and a few higher redshift quasars. Here we show the clear detection of a powerful AGN accretion disk wind with a mildly relativistic velocity of 0.25c in the X-ray spectrum of IRAS F11119+3257, a nearby (z = 0.189) optically classified type 1 ULIRG hosting a powerful molecular outflow. The AGN is responsible for ~80% of the emission, with a quasar-like luminosity of L_AGN = 1.5x10^46 erg/s. The energetics of these winds are consistent with the energy-conserving mechanism, which is the basis of the quasar mode feedback in AGN lacking powerful radio jets., Revised file including the letter, methods and supplementary information. Published in the March 26th 2015 issue of Nature

The Narrow-line Seyfert I galaxy, 1H0707-495, has been well observed in the 0.3-10 keV band, revealing a dramatic drop in flux in the iron K alpha band, a strong soft excess, and short timescale reverberation lags associated with these spectral features. In this paper, we present the first results of a deep 250 ks NuSTAR observation of 1H0707-495, which includes the first sensitive observations above 10 keV. Even though the NuSTAR observations caught the source in an extreme low-flux state, the Compton hump is still significantly detected. NuSTAR, with its high effective area above 7 keV, clearly detects the drop in flux in the iron K alpha band, and by comparing these observations with archival XMM-Newton observations, we find that the energy of this drop increases with increasing flux. We discuss possible explanations for this, the most likely of which is that the drop in flux is the blue wing of the relativistically broadened iron K alpha emission line. When the flux is low, the coronal source height is low, thus enhancing the most gravitationally redshifted emission., Submitted to MNRAS, comments are welcome. 9 pages, 5 figures

We present X-ray timing and spectral analyses of simultaneous 150 ks Nuclear Spectroscopic Telescope Array (NuSTAR) and Suzaku X-ray observations of the Seyfert 1.5 galaxy NGC 4151. We disentangle the continuum emission, absorption, and reflection properties of the active galactic nucleus (AGN) by applying inner accretion disk reflection and absorption-dominated models. With a time-averaged spectral analysis, we find strong evidence for relativistic reflection from the inner accretion disk. We find that relativistic emission arises from a highly ionized inner accretion disk with a steep emissivity profile, which suggests an intense, compact illuminating source. We find a preliminary, near-maximal black hole spin a>0.9 accounting for statistical and systematic modeling errors. We find a relatively moderate reflection fraction with respect to predictions for the lamp post geometry, in which the illuminating corona is modeled as a point source. Through a time-resolved spectral analysis, we find that modest coronal and inner disk reflection flux variation drives the spectral variability during the observations. We discuss various physical scenarios for the inner disk reflection model, and we find that a compact corona is consistent with the observed features., 20 pages, 12 figures, accepted for publication in ApJ

We report on four epochs of observations of the quasar PG 1211+143 using NuSTAR. The net exposure time is 300 ks. Prior work on this source found suggestive evidence of an 'ultra-fast outflow' (or, UFO) in the Fe K band, with a velocity of approximately 0.1c. The putative flow would carry away a high mass flux and kinetic power, with broad implications for feedback and black hole-galaxy co-evolution. NuSTAR detects PG 1211+143 out to 30 keV, meaning that the continuum is well-defined both through and above the Fe K band. A characteristic relativistic disk reflection spectrum is clearly revealed, via a broad Fe K emission line and Compton back-scattering curvature. The data offer only weak constraints on the spin of the black hole. A careful search for UFO's show no significant absorption feature above 90% confidence. The limits are particularly tight when relativistic reflection is included. We discuss the statistics and the implications of these results in terms of connections between accretion onto quasars, Seyferts, and stellar-mass black holes, and feedback into their host environments., Comment: Accepted in ApJL

In the past five years, a flurry of X-ray reverberation lag measurements of accreting supermassive black holes have been made using the XMM-Newton telescope in the 0.3-10 keV energy range. In this work, we use the NuSTAR telescope to extend the lag analysis up to higher energies for two Seyfert galaxies, SWIFT J2127.4+5654 and NGC 1365. X-ray reverberation lags are due to the light travel time delays between the direct continuum emission and the reprocessed emission from the inner radii of an ionised accretion disc. XMM-Newton has been particularly adept at measuring the lag associated with the broad Fe K emission line, where the gravitationally redshifted wing of the line is observed to respond before the line centroid at 6.4 keV, produced at larger radii. Now we use NuSTAR to probe the lag at higher energies, where the spectrum shows clear evidence for Compton reflection, known as the Compton 'hump'. The XMM-Newton data show Fe K lags in both SWIFT J2127.4+5654 and NGC 1365. The NuSTAR data provide independent confirmation of these Fe K lags, and also show evidence for the corresponding Compton hump lags, especially in SWIFT J2127.4+5654. These broadband lag measurements confirm that the Compton hump and Fe K lag are produced at small radii. At low-frequencies in NGC 1365, where the spectrum shows evidence for eclipsing clouds in the line of sight, we find a clear negative (not positive) lag from 2--10 keV, which can be understood as the decrease in column density from a neutral eclipsing cloud moving out of our line of sight during the observation., Comment: 14 Pages, 12 figures, accepted to MNRAS

We have conducted an archival XMM-Newton study of the bright X-ray point sources in 32 nearby galaxies. From our list of approximately 100 point sources, we attempt to determine if there is a low-state counterpart to the Ultraluminous X-ray (ULX) population. Indeed, 16 sources in our sample match the criteria we set for a low-state ULX, namely, L(sub X) greater than 10(exp 38 ergs per second) and a spectrum best fit with an absorbed power law. Further, we find evidence for 26 high-state ULXs which are best fit by a combined blackbody and a power law. As in Galactic black hole systems, the spectral indices, GAMMA, of the low-state objects, as well a s the luminosities, tend to be lower than those of the high-state objects. The observed range of blackbody temperatures is 0.1-1 keV with the most luminous systems tending toward the lowest temperatures. We also find a class of object whose properties (luminosity, blackbody temperature, and power law slopes) are very similar to those of galactic stellar mass black holes. In addition, we find a subset of these objects that can be best fit by a Comptonized spectrum similar to that used for Galactic black holes in the very high state, when they are radiating near the Eddington limit.

We have searched for evidence of soft X-ray absorption by hot metals in the vicinity of the Galaxy in the spectra of a small sample of fifteen Type I AGN observed with the high resolution X-ray gratings on board Chandra. This is an extension of our previous survey of hot OVII and OVIII absorbing gas in the vicinity of the Galaxy. The strongest absorption signatures within a few hundred km/s of their rest-frame energies are most likely due to warm absorbing outflows from the nearest AGN, which are back-lighting the local hot gas. We emphasize that absorption signatures in the spectra of some distant AGN that are kinematically consistent with the recessional velocity of the AGN are most likely to be due to hot local gas. Along the sightline towards PG 1211+143, PDS 456 and MCG-6-30-15 there is a very large absorbing Fe column density which is kinematically consistent with absorption by hot, local Fe. The sightlines to these three AGN pass through the limb of the Northern Polar Spur (NPS), a local bubble formed from several supernovae which, if rich in Fe, may account for a large local Fe column. We obtain limits on the column density of local, highly ionized N, Ne, Mg, Si along all of the sightlines in our sample. We correlate the column density limits with those of highly ionized O along the same sightlines. Assuming the hot local gas is in collisionally ionized equilibrium, we obtain limits on the temperature and relative abundances of the metals in the hot local gas. Our limits on the ionic column densities in the local hot gas seem to be consistent with those observed in the hot halo gas of edge-on normal spiral galaxies., Comment: 9 pages,2 figures, MNRAS (accepted)

Ideal hydrodynamic models of the intracluster medium (ICM) in the core regions of galaxy clusters fail to explain both the observed temperature structure of this gas, and the observed morphology of radio-galaxy/ICM interactions. It has recently been suggested that, even in the presence of reasonable magnetic fields, thermal conduction in the ICM may be crucial for reproducing the temperature floor seen in many systems. If this is indeed correct, it raises the possibility that other transport processes may be important. With this motivation, we present a numerical investigation of the buoyant evolution of AGN-blown cavities in ICM that has a nonnegligible shear viscosity. We use the ZEUS-MP code to follow the three-dimensional evolution of an initially static, hot bubble in a β-model ICM atmosphere with varying degrees of shear viscosity. With no explicit viscosity, it is found that the combined action of Rayleigh‐Taylor and Kelvin‐Helmholtz instabilities rapidly shred the ICM cavity and one does not reproduce the intact and detached ‘ghost cavities’ observed in systems such as Perseus-A. On the other hand, even a modest level of shear viscosity (corresponding to approximately 25 per cent of the Spitzer value) can be important in quenching the fluid instabilities and maintaining the integrity of the bubble. In particular, we show that the morphology of the north-west ghost cavity found in Perseus-A can be reproduced, as can the flow pattern inferred from the morphology of Hα filaments. Finally, we discuss the possible relevance of ICM viscosity to the fact that many of the active ICM cavities (i.e. those currently associated with active radio lobes) are not bounded by strong shocks, the so-called ‘shock problem’. Ke yw ords: hydrodynamics ‐ cooling flows ‐ galaxies: jets ‐ X-rays: galaxies: clusters.

We present an observation of the radio-galaxy 3C401 and the surrounding intracluster medium (ICM) of its host galaxy cluster by the Chandra X-ray Observatory. This luminous radio-galaxy is notable in that it has characteristics intermediate between the FRI and FRII morphologies. We clearly detect point-like emission coincident with the radio-core of 3C401, although the spatial resolution of even Chandra is only 2kpc at the distance of 3C401 (z=0.201) and so the possibility remains that this is a dense (and rapidly cooling) thermal gaseous core in the center of the ICM atmosphere. Strong departures from spherical symmetry in the central 10-20kpc of the ICM clearly suggest interaction between the ICM and the radio-lobes of 3C401. A central X-ray bar probably results from the evacuation of two ICM cavities by the expanding radio lobes. Beyond these central regions, the cluster possesses a flatter profile than many clusters of comparable mass suggesting the importance of ICM heating and entropy injection by 3C401. We detect an interesting cross-like structure in the ICM on 100kpc scales. We speculate that this could be a radio-galaxy induced disturbance corresponding to a time when 3C401 was substantially more powerful. A particularly exciting possibility is that this cross-like structure corresponds to a large scale global g-mode oscillation excited by a past outburst of 3C401.

(abridged) We searched for evidence of soft X-ray absorption by hot gas in the vicinity of the Galaxy in a small sample of fifteen type I AGN observed with the high resolution X-ray gratings on board Chandra. We find that around half of the sight lines in our sample exhibit absorption due to local H- or He-like Oxygen (or both) at confidence levels ranging from >90% to >3sigma. Depending on the sight line, the absorption can be identified with hot gas in particular local structures, the Local Group (LG) or the putative local hot intergalactic medium (IGM). Several sight lines in our sample coincide with sight lines in a study of O VI absorption by local gas, so an assumption of collisional ionization equilibrium (CIE) allows us to constrain the temperature of the local hot gas. We show that some portion of the hot absorbing outflows apparently detected in the spectra of NGC 4051, PDS 456 and PG 1211+143 respectively could actually correspond to absorption by hot local gas since the outflow velocity from each of these AGN coincides with the respective cosmological recession velocity of the AGN., 8 pages. Modified discussion of Fe-K band absorption features in PDS 456 and PG 1211+143

We present an analysis of the 2-10keV XMM-Newton/EPIC-pn spectrum of the Seyfert-1 galaxy NGC4593. Apart from the presence of two narrow emission lines corresponding to the Kalpha lines of cold and hydrogen-like iron, this spectrum possesses a power-law form to within 3-5%. There is a marked lack of spectral features from the relativistic regions of the black hole accretion disk. We show that the data are, however, consistent with the presence of a radiatively-efficient accretion disk extending right down to the radius of marginal stability if it possesses low iron abundance, an appropriately ionized surface, a very high inclination, or a very centrally concentrated emission pattern (as has been observed during the Deep Minimum State of the Seyfert galaxy MCG-6-30-15). Deeper observations of this source are required in order to validate or reject these models., Comment: 6 pages, 3 postscript figures. Accepted for publication in the Monthly Notices of the Royal Astronomical Society

(abridged) We present a detailed reanalysis of the Chandra data for the galaxy cluster Abell 4059 and its central radio galaxy, PKS2354-35. We also present new 1.4GHz and 4.7GHz CnB-array radio data from the Very Large Array (VLA), as well as a short archival WFPC2 image from the Hubble Space Telescope. The presence of a strong interaction between this radio galaxy and the intracluster medium (ICM) was suggested by Huang & Sarazin (1998) on the basis of a short observation by the High Resolution Imager on ROSAT, and confirmed in our preliminary analysis of the Chandra/ACIS-S data. In particular, X-ray imaging clearly shows two cavities within the ICM that are approximately aligned with the radio-galaxy axis. However, using our new radio maps we fail to find a detailed correspondence between the 1 arcmin scale radio-lobes and the ICM cavities. This suggests that the cavities are ``ghosts'' of a previous burst of powerful activity by PKS 2354-35. We also examine the nature of the central asymmetric ridge (or bar) of X-ray emission extending for 30kpc south-west of the cluster center that has been noted in these previous analyzes. We find the ridge to be denser and cooler than, but probably in pressure balance with, its surroundings. The thermal evolution of this structure seems to be dominated by radiative cooling, possibly enhanced by the radio-galaxy ICM interaction. We discuss several possible models for the formation of this SW ridge and find none of them to be entirely satisfactory.

We have analyzed spectra of the Galactic black hole GX 339-4 obtained through simultaneous 76 ksec XMM-Newton/EPIC-pn and 10 ksec RXTE observations during a bright phase of its 2002-2003 outburst. An extremely skewed, relativistic Fe K-alpha emission line and ionized disk reflection spectrum are revealed in these spectra. Self-consistent models for the Fe K-alpha emission line profile and disk reflection spectrum rule-out an inner disk radius compatible with a Schwarzschild black hole at more than the 8 sigma level of confidence. The best-fit inner disk radius of 2-3 r_g suggests that GX 339-4 harbors a black hole with a ~ 0.8-0.9 (where r_g = GM/c^2 and a=cJ/GM^2, and assuming that reflection in the plunging region is relatively small). This confirms indications for black hole spin based on a Chandra spectrum obtained later in the outburst. The emission line and reflection spectrum also rule-out a standard power-law disk emissivity in GX 339-4; a broken power-law form with enhanced emissivity inside ~6 r_{g} gives improved fits at more than the 8 sigma level of confidence. The extreme red wing of the line and steep emissivity require a centrally--concentrated source of hard X-rays which can strongly illuminate the inner disk. Hard X-ray emission from the base of a jet - enhanced by gravitational light bending effects - could create the concentrated hard X-ray emission; this process may be related to magnetic connections between the black hole and the inner disk. We discuss these results within the context of recent results from analyses of XTE J1650-500 and MCG-6-30-15, and models for the inner accretion flow environment around black holes., Comment: 5 pages, 2 color figures, uses emulateapj.sty and apjfonts.sty, ApJ Letters, accepted

The Fe Kα lines seen in many Active Galactic Nuclei (AGN) are thought to originate close to the central supermassive black hole. In this review we summarize the physics of the fluorescent line formation and show that Fe Kα line profile observations can be used to probe relativistic effects in the vicinity of the black hole, concentrating on recent results from XMM-Newton.

(abridged) With most physicists and astrophysicists in agreement that black holes do indeed exist, the focus of astrophysical black hole research has shifted to the detailed properties of these systems. Nature has provided us with an extremely useful probe of the region very close to an accreting black hole - X-ray irradiation of relatively cold material in the vicinity of the black hole can imprint characteristic features into the X-ray spectra of black hole systems, most notably the Kalpha fluorescent line of iron. Detailed X-ray spectroscopy of these features can be used to study Doppler and gravitational redshifts, thereby providing key information on the location and kinematics of the cold material. This is a powerful tool that allows us to probe within a few gravitational radii, or less, of the event horizon. Here, we present a comprehensive review of relativistic iron line studies for both accreting stellar mass black holes (i.e., Galactic Black Hole Candidate systems; GBHCs), and accreting supermassive black holes (i.e., active galactic nuclei; AGN). After a pedagogical introduction to black hole astrophysics, we discuss studies of relativistic iron lines in the AGN context and show how differences between classes of AGN can be diagnosed using X-ray spectroscopy. Furthermore, through a detailed discussion of one particular object (MCG--6-30-15), we illustrate how the exotic physics of black hole spin are now open to observational study. We proceed to discuss GBHCs, which turn out to possess rather more complicated X-ray spectra, making robust conclusions more difficult to draw. However, even in these cases, modern X-ray observatories are now providing convincing evidence for relativistic effects. We conclude by discussing the science that can be addressed by future X-ray observatories., 103 pages, 21 figures. To be published in Physics Reports, vol. 377, pp.389. Minor typos and references corrected from previous version

Broad Fe K-alpha emission lines have recently been reported in a number of Galactic black holes. Such lines are useful accretion flow diagnostics because they may be produced at the inner accretion disk and shaped by relativistic effects, but in general they have only been observed at luminosities of L_X ~ 10^(37-38) erg/s in soft X-rays. The Galactic microquasar V4641 Sgr -- widely known for its 12.2 Crab (1.5-12 keV) outburst in 1999 September -- displayed low-level activity in 1999 March. BeppoSAX observed the source in this state and Fe K-alpha line emission was found (in 't Zand et al. 2000). In re-analyzing these data, we find strong evidence that the Fe K-alpha line profile is broadened. For the most likely values of the source distance and black hole mass measured by Orosz et al. (2001), our fits to the total spectrum indicate that the source was observed at a luminosity of L_X = 1.9 (+1.0, -0.8) * 10^(36) erg/s (2-10 keV), or L_X/L_Edd. = 1.8 (+0.9, -0.8) * 10^(-3). Advection-dominated accretion flow (ADAF) models predict a radially-recessed disk in this regime. In contrast, fits to the observed Fe K-alpha emission line profile with a relativistic line model constrain the inner disk to be consistent with the marginally stable circular orbit of a Schwarzschild black hole.

We observed the Galactic black hole candidate XTE J1650-500 early in its Fall, 2001 outburst with the XMM-Newton European Photon Imaging pn Camera (EPIC-pn). The observed spectrum is consistent with the source having been in the "very high" state. We find a broad, skewed Fe K-alpha emission line which suggests that the primary in this system may be a Kerr black hole, and which indicates a steep emissivity profile that is hard to explain in terms of a standard accretion disk model. These results are quantitatively and qualitatively similar to those from an XMM-Newton observation of the Seyfert galaxy MCG--6-30-15. The steep emissivity in MCG--6-30-15 may be explained by the extraction and dissipation of rotational energy from a black hole with nearly- maximal angular momentum or material in the plunging region via magnetic connections to the inner accretion disk. If this process is at work in both sources, an exotic but fundamental general relativistic prediction may be confirmed across a factor of 10^6 in black hole mass. We discuss these results in terms of the accretion flow geometry in stellar-mass black holes, and the variety of enigmatic phenomena often observed in the very high state.

We present 3-band HST imaging of three nearby (z

We present a numerical investigation of dead, or relic, radio galaxies and the environmental impact that radio galaxy activity has on the host galaxy or galaxy cluster. We perform axisymmetric hydrodynamical calculations of light, supersonic, back-to-back jets propagating in a beta-model galaxy/cluster atmosphere. We then shut down the jet activity and let the resulting structure evolve passively. The dead source undergoes an initial phase of pressure driven expansion until it achieves pressure equilibrium with its surroundings. Thereafter, buoyancy forces drive the evolution and lead to the formation of two oppositely directed plumes that float high into the galaxy/cluster atmosphere. These plumes entrain a significant amount of low entropy material from the galaxy/cluster core and lift it high into the atmosphere. An important result is that a large fraction (at least half) of the energy injected by the jet activity is thermalized in the ISM/ICM core. The whole ISM/ICM atmosphere inflates in order to regain hydrostatic equilibrium. This inflation is mediated by an approximately spherical disturbance which propagates into the atmosphere at the sound speed. The fact that such a large fraction of the injected energy is thermalized suggests that radio galaxies may have an important role in the overall energy budget of rich ISM/ICM atmospheres. In particular, they may act as a strong and highly time-dependent source of negative feedback for galaxy/cluster cooling flows., Comment: 13 pages, 20 postscript figures. Accepted for publication in the Monthly Notices of the Royal Astronomical Society

We present Chandra observations of the galaxy cluster A4059. We find strong evidence that the FR-I radio galaxy PKS 2354-35 at the center of A4059 is inflating cavities with radii ~20 kpc in the intracluster medium, similar to the situation seen in Perseus A and Hydra A. We also find evidence for interaction between the intracluster medium and PKS 2354-35 on small scales in the very center of the cluster. Arguments are presented suggesting that this radio galaxy has faded significantly in radio power (possibly from an FR-II state) over the past 10^8 yrs., Accepted for publication in ApJ Letters; figure 1a also included as high quality JPEG file for convenience

The Chandra AO1 HETGS observation of the micro-quasar GRS 1915+105 in the low hard state reveals (1) neutral K absorption edges from Fe, Si, Mg, and S in cold gas, and (2) highly ionized (Fe XXV and Fe XXVI) absorption attributed to a hot disk, disk wind, or corona. The neutral edges reveal anomalous Si and Fe abundances which we attribute to surrounding cold material in/near the environment of GRS 1915+105. We also point out the exciting possibility for the first astrophysical detection of XAFS attributed to material in interstellar grains. We place constraints on the ionization parameter, temperature, and hydrogen equivalent number density of the absorber near the accretion disk based on the detection of the H- and He-like Fe absorption. Observed spectral changes in the ionized lines which track the light curve point to changes in both the ionizing flux and density of the absorber, supporting the presence of a flow. Details can be found in Lee et al., 2002, ApJ., 567, 1102

We show the combined spectral analysis of \emph{Chandra} high energy transmission grating (HETG) and \emph{XMM-Newton} reflection grating spectrometer (RGS) observations of the broad-line radio galaxy 3C 111. The source is known to show excess neutral absorption with respect to the one estimated from 21 cm radio surveys of atomic H I in the Galaxy. However, previous works were not able to constrain the origin of such absorber as local to our Milky Way or intrinsic to the source ($z = 0.0485$). The high signal-to-noise grating spectra allow us to constrain the excess absorption as due to intervening gas in the Milky Way, and we estimate a time averaged total column density of $N_H = (7.4\pm0.1)\times 10^{21}$ cm$^{-2}$, a factor of two higher than the tabulated H I value. We recommend to use the total average Galactic column density here estimated when studying 3C 111. The origin of the extra Galactic absorption of $N_H = 4.4\times 10^{21}$ cm$^{-2}$ is likely due to molecular gas associated with the Taurus molecular cloud complex toward 3C 111, which is our nearest star-forming region. We also detect a weak (EW$=$$16\pm10$ eV) and narrow (FWMH$, Comment: Accepted for publication in ApJ

Measurements of the high-energy cut-off in the coronal continuum of active galactic nuclei have long been elusive for all but a small number of the brightest examples. We present a direct measurement of the cut-off energy in the nuclear continuum of the nearby Seyfert 1.9 galaxy MCG -05-23-016 with unprecedented precision. The high sensitivity of NuSTAR up to 79 keV allows us to clearly disentangle the spectral curvature of the primary continuum from that of its reflection component. Using a simple phenomenological model for the hard X-ray spectrum, we constrain the cut-off energy to $116_{-5}^{+6}$ keV with 90% confidence. Testing for more complex models and nuisance parameters that could potentially influence the measurement, we find that the cut-off is detected robustly. We further use simple Comptonized plasma models to provide independent constraints for both the kinetic temperature of the electrons in the corona and its optical depth. At the 90% confidence level, we find $kT_e=29\pm2$ keV and $\tau_e=1.23\pm0.08$ assuming a slab (disk-like) geometry, and $kT_e=25\pm2$ keV and $\tau_e=3.5\pm0.2$ assuming a spherical geometry. Both geometries are found to fit the data equally well and their two principal physical parameters are correlated in both cases. With the optical depth in the optically thick regime, the data are pushing the currently available theoretical models of the Comptonized plasma to the limits of their validity. Since the spectral features and variability arising from the inner accretion disk have been observed previously in MCG -05-23-016, the inferred high optical depth implies that a spherical or disk-like corona cannot be homogeneous., Comment: 7 pages, 2 figures. Accepted for publication in ApJ

We present a deep Suzaku observation of H1821+643, an extremely rare example of a powerful quasar hosted by the central massive galaxy of a rich cooling-core cluster of galaxies. Informed by previous Chandra studies of the cluster, we achieve a spectral separation of emission from the active galactic nucleus (AGN) and the intracluster medium (ICM). With a high degree of confidence, we identify the signatures of X-ray reflection/reprocessing by cold and slowly moving material in the AGN's immediate environment. The iron abundance of this matter is found to be significantly sub-solar (Z~0.4Zsun), an unusual finding for powerful AGN but in line with the idea that this quasar is feeding from the ICM via a Compton-induced cooling flow. We also find a subtle soft excess that can be described phenomenologically (with an additional black body component) or as ionized X-ray reflection from the inner regions of a high inclination (i=57 degrees) accretion disk around a spinning (a>0.4) black hole. We describe how the ionization state of the accretion disk can be used to constrain the Eddington fraction of the source. Applying these arguments to our spectrum implies an Eddington fraction of 0.25-0.5, with an associated black hole mass of 3-6x10^9Msun., 5 pages, accepted for publication in The Astrophysical Journal Letters