Broad Iron-Kα Emission Lines as a Diagnostic of Black Hole Spin

  title={Broad Iron-K$\alpha$ Emission Lines as a Diagnostic of Black Hole Spin},
  author={Christopher S. Reynolds and Andrew C. Fabian},
  journal={The Astrophysical Journal},
We address the ability of broad iron emission lines from black hole accretion disks to diagnose the spin of the black hole. Using a high-resolution three-dimensional MHD simulation of a geometrically thin accretion disk in a pseudo-Newtonian potential, we show that both the mid-plane density and the vertical column density of the accretion flow drop dramatically over a narrow range of radii close to the innermost stable circular orbit (ISCO). We argue that this drop of density is accompanied by… 

Figures from this paper

A rapidly spinning supermassive black hole at the centre of NGC 1365
X-ray observations of NGC 1365 are reported that reveal the relativistic disk features through broadened Fe-line emission and an associated Compton scattering excess of 10–30 kiloelectronvolts.
Role of emission angular directionality in spin determination of accreting black holes with a broad iron line
Aims. The spin of an accreting black hole can be determined by spectroscopy of the emission and absorption features produced in the inner regions of an accretion disc. In this work, we discuss the
Accretion disk reflection spectra, including broad iron emission lines, bear the imprints of the strong Doppler shifts and gravitational redshifts close to black holes. The extremity of these shifts
X-Ray Spectra from Magnetohydrodynamic Simulations of Accreting Black Holes
We present the results of a new global radiation transport code coupled to a general relativistic magnetohydrodynamic simulation of an accreting, non-rotating black hole. For the first time, we are
Black hole accretion rings revealed by future X-ray spectroscopy
Spectral features can arise by reflection of coronal X-rays on a black hole accretion disc. The resulting profile bears various imprints of a strong gravitational field acting on the light-emitting
Reflection Spectra of Accretion Disks Illuminated by Disk-like Coronae
Relativistic reflection features in the X-ray spectra of black hole binaries and active galactic nuclei are thought to be produced through illumination of a cold accretion disk by a hot corona. In
The Central Engine Structure of 3C120: Evidence for a Retrograde Black Hole or a Refilling Accretion Disk
The broad-line radio galaxy 3C120 is a powerful source of both X-ray and radio emission including superluminal jet outflows. We report on our reanalysis of 160 ks of Suzaku data taken in 2006,
Angular Momentum Transport in Accretion Disks and Its Implications for Spin Estimates in Black Hole Binaries
The accretion flow in the disk-dominated state of black hole binaries has a peak temperature and luminosity that vary together in such a way as to indicate an approximately constant emitting area.
An intermediate black hole spin in the NLS1 galaxy SWIFT J2127.4+5654: chaotic accretion or spin energy extraction?
We have observed the hard X-ray selected Narrow-Line Seyfert 1 galaxy SWIFT J2127.4+5654 with Suzaku. We report the detection of a broad relativistic iron emission line from the inner accretion disc.
Measuring the Spins of Accreting Black Holes
A typical galaxy is thought to contain tens of millions of stellar-mass black holes, the collapsed remnants of once massive stars, and a single nuclear supermassive black hole. Both classes of black


Iron line profiles including emission from within the innermost stable orbit of a black hole accretion disc
Reynolds &38; Begelman have recently proposed a model in which the broad and extremely redshifted iron line seen during a deep minimum of the light curve of the Seyfert 1 galaxy MCG–6-30-15
Constraining Black Hole Spin via X-Ray Spectroscopy
We present an analysis of the observed broad iron line feature and putative warm absorber in the long 2001 XMM-Newton observation of the Seyfert 1.2 galaxy MCG -06-30-15. The new kerrdisk model we
Iron Fluorescence from within the Innermost Stable Orbit of Black Hole Accretion Disks
The fluorescent iron Kα line is a powerful observational probe of the inner regions of black hole accretion disks. Previous studies have assumed that only material outside the radius of marginal
The profile and equivalent width of the X-ray iron emission line from a disc around a Kerr black hole
Recent X-ray observations have shown broad, skewed iron line emission from Seyfert 1 galaxies which is explained by the emission being fluorescence on a disk close to a black hole. During one
The Spin of the Near-Extreme Kerr Black Hole GRS 1915+105
Based on a spectral analysis of the X-ray continuum that employs a fully relativistic accretion disk model, we conclude that the compact primary of the binary X-ray source GRS 1915+105 is a rapidly
X-Ray Iron Line Reverberation from Black Hole Accretion Disks
The relativistically broad X-ray iron line seen in many active galactic nucleus (AGN) spectra is thought to originate from the central regions of the putative black hole accretion disk. Both the line
A light bending model for the X-ray temporal and spectral properties of accreting black holes
Some of the X-ray temporal and spectral properties of accreting black holes represent a challenge for current theoretical models. In particular, uncorrelated variability between direct continuum and
A Variable Efficiency for Thin-Disk Black Hole Accretion
We explore the presence of torques at the inner edges of geometrically thin black hole accretion disks using three-dimensional MHD simulations in a pseudo-Newtonian potential. By varying the
A measurement of the electromagnetic luminosity of a kerr black hole
Some active galactic nuclei, microquasars, and gamma-ray bursts may be powered by the electromagnetic braking of a rapidly rotating black hole. We investigate this possibility via axisymmetric