Constraining Black Hole Spin Via X-ray Spectroscopy

Abstract

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-6-30-15. The new "kerrdisk" model we have designed for simulating line emission from accretion disk systems allows black hole spin to be a free parameter in the fit, enabling the user to formally constrain the angular momentum of a black hole, among other physical parameters of the system. In an important extension of previous work, we derive constraints on the black hole spin in MCG-6-30-15 using a self-consistent model for X-ray reflection from the surface of the accretion disk while simultaneously accounting for absorption by dusty photoionized material along the line of sight (the warm absorber). Even including these complications, the XMM-Newton/EPIC-pn data require extreme relativistic broadening of the X-ray reflection spectrum; assuming no emission from within the radius of marginal stability, we derive a formal constraint on the dimensionless black hole spin parameter of a > 0.987 at 90% confidence. The principal unmodeled effect that can significantly reduce the inferred black hole spin is powerful emission from within the radius of marginal stability. Although significant theoretical developments are required to fully understand this region, we argue that the need for a rapidly spinning black hole is robust to physically plausible levels of emission from within the radius of marginal stability. In particular, we show that a non-rotating black hole is strongly ruled out.

42 pages, 10 figures, accepted for publication in the Astrophysical Journal as of 7/06. To download the models used in this paper, please go to http://www.astro.umd.edu/~chris/kerrdisk/kerrdisk_model.html

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• Wavelet spectral timing: X-ray reverberation from a dynamic black hole corona hidden beneath ultrafast outflows
• Testing the Kerr metric using X-ray reflection spectroscopy: spectral analysis of GX 339-4
• Curved accretion disks around rotating black holes without reflection symmetry
• Extreme lensing induces spectro-temporal correlations in black-hole signals
• Dependence of the broad Fe K$\alpha$ line on the physical parameters of AGN
• Black Holes as Fermion Factories
• Constraints on Spin of a Supermassive Black Hole in Quasars with Big Blue Bump
• Changing Accretion Geometry of Seyfert 1 Mrk 335 with {\it NuSTAR}: A Comparative Study
• Thermal spectra of thin accretion disks of finite thickness around Kerr black holes
• Measuring Black Hole Spins through X-ray Reflection Spectroscopy and the Relativistic Precession Model: the case of XTE J1859+226
• Testing the Keplerian disk hypothesis using X-ray reflection spectroscopy
• Constraints on the radio loud/radio quiet dichotomy from the fundamental plane
• QPOs from Random X-ray Bursts around Rotating Black Holes
• Reflection features in the X-ray spectrum of Fairall 9 and implications for tests of general relativity
• The Spin of a Newborn Black Hole: Swift J1728.9-3613
• Disentangling the AGN and Star-Formation Contributions to the Radio-X-ray Emission of Radio-Loud Quasars at 1<z<2
• Strong field effects on emission line profiles: Kerr black holes and warped accretion disks
• The Distribution and Cosmic Density of Relativistic Iron Lines in Active Galactic Nuclei
• Null geodesics in extremal Kerr-Newman black holes
• The Effect of Microlensing On the Observed X-ray Energy Spectra of Gravitationally Lensed Quasars
• Effect of accreting tidally disrupted stars on the spin evolution of $\sim 10^6{M}_{\odot }$ black holes
• The NuSTAR View of a QPO Evolution of GRS 1915+105
• Relativistic reflection spectra of super-spinning black holes
• Unwrapping the X-ray Spectra of Active Galactic Nuclei
• Testing Gravity with Black Hole X-Ray Data
• Insight-HXMT, NICER and NuSTAR views to the newly discovered black hole X-ray binary Swift J151857.0--572147
• Impact of the cosmic neutrino background on black hole superradiance
• Astrophysics with the Laser Interferometer Space Antenna
• Constraints on black hole spins with a general relativistic accretion disk corona model
• A Spectroscopic Angle on Central Engine Size Scales in Accreting Neutron Stars
• Exploring higher order images with Fe K_α-lines from relativistic disks: black hole spin determination and bias
• The Iron Line Profile from Warped Black Hole Accretion Disks
• Probing the Extent of Fe K$\alpha$ Emission in Nearby Active Galactic Nuclei using Multi-Order Analysis of Chandra High Energy Transmission Grating Data
• Acceleration of charged particles from near-extremal rotating black holes embedded in magnetic fields
• Detection of the Fe K lines from the binary AGN in 4C+37.11
• Probing the origin of the iron K_alpha line around stellar and supermassive black holes using X-ray polarimetry
• Emission lines from X-ray illuminated accretion disc in black hole binaries
• Fermionic Love of Black Holes in General Relativity
• The Aretakis constants and instability in general spherically symmetric extremal black hole spacetimes: higher multipole modes, late-time tails, and geometrical meanings
• Relativistic Reflection Modeling in AGN and Related Variability from PCA: A Brief Review
• Neutron Star Radius-to-mass Ratio from Partial Accretion Disc Occultation as Measured through Fe K$\alpha$ Line Profiles
• The population of NuSTAR Black Hole X-ray Binaries
• Magnetic Coupling of a Rotating Black Hole with Advection-Dominated Accretion Flows
• The Integrated Relativistic Iron Line from Active Galactic Nuclei: Chasing the Spin Evolution of Supermassive Black Holes
• Unlocking the nature of ultraluminous X-ray sources using their X-ray spectra
• Could the dynamics of the Universe be influenced by what is going on inside black holes?
• Gravitational Fields of the Magnetic-type
• Cosmic spin and mass evolution of black holes and its impact
• Morphology of Relativistically Broadened Line Emission from Axisymmetric Equatorial Accretion Disks
• On the Zeeman Effect in Magnetically-Arrested Disks
• Stellar-Mass Black Holes
• The Reliability of Accretion Disk Inclination Derived from X-ray Spectroscopy of Active Galaxies
• Origin of the X-ray Broad Iron Spectral Feature in GRS 1915+105
• Scalar Self-force for High Spin Black Holes
• Testing General Relativity with Black Hole X-ray Data
• X-ray reflection spectroscopy with improved calculations of the emission angle
• Constraining black hole spin in PG 1535+547 amidst complex multi-layered absorption
• A study for testing the Kerr metric with AGN iron line eclipses
• Modeling reflection spectra of super-Eddington X-ray sources
• A truncated inner disc in the Seyfert 1 galaxy WKK 4438
• Testing the Kerr black hole hypothesis with RELXILL_NK
• Near-Horizon Collisions around Near-Extremal Black Holes
• Black Holes at Work
• Accretion Geometry of Black Hole X-ray Binaries: Insights from X-ray Observations
• Iron Line Tomography of General Relativistic Hydrodynamic Accretion around Kerr Black Holes
• Testing General Relativity with Black Holes
• The Effects of Complex Accretion Disk Geometry on Broadened Iron K$\alpha$ Lines
• Strong gravity effects: X-ray spectra, variability and polarimetry
• Multimission Observations of GS 1354-64 during the 2025-2026 Outburst: First Results
• Testing general relativity with X-ray reflection spectroscopy of MCG-06-30-15