Exploring higher order images with Fe K_α-lines from relativistic disks: black hole spin determination and bias

Abstract

We study the contributions to the relativistic Fe $K_{\alpha }$ line profile from higher order images (HOIs) produced by strongly deflected rays from the disk which cross the plunging region, located between the innermost stable circular orbit (ISCO) radius and the event horizon of a Kerr black hole. We investigate the characteristics features imprinted by the HOIs in the line profile for different black hole spins, disk emissivity laws and inclinations. We find that they extend from the red wing of the profile up to energies slightly lower than those of the blue peak, adding $\sim 0.4-1.3$\% to the total line flux. The contribution to the specific flux is often in the $\sim 1$\% to 7\% range, with the highest values attained for low and negative spin ($a\lesssim 0.3$) black holes surrounded by intermediate inclination angle ($i\sim 40^{\circ }$) disks. We simulate future observations of a black hole X-ray binary system with the Large Area Detector of the planned X-ray astronomy \emph{enhanced X-ray Timing and Polarimetry Mission} (eXTP) and find that the \fekal\ of systems accreting at $\lesssim 1$\% the Eddington rate are affected by the HOI features for a range of parameters. This would provide evidence of the extreme gravitational lensing of HOI rays. Our simulations show also that not accounting for HOI contributions to the Fe $K_{\alpha }$ line profile may systematically bias measurements of the black hole spin parameter towards values higher by up to $\sim 0.3$ than the inputted ones.

arXiv commentaccepted for publication in MNRAS, 11 pages, 7 figures, 2 tables

References in corpus (58)

• On the Absorption of X-rays in the Interstellar Medium
• GWTC-1: A Gravitational-Wave Transient Catalog of Compact Binary Mergers Observed by LIGO and Virgo during the First and Second Observing Runs
• Advection-Dominated Accretion: Underfed Black Holes and Neutron Stars
• The Assembly and Merging History of Supermassive Black Holes in Hierarchical Models of Galaxy Formation
• Black holes, gravitational waves and fundamental physics: a roadmap
• Thermal Equilibria of Accretion Disks
• Broad iron lines in Active Galactic Nuclei
• Constraining Black Hole Spin Via X-ray Spectroscopy
• Measurement of the Kerr Spin Parameter by Observation of a Compact Object's Shadow
• Fluorescent iron lines as a probe of astrophysical black hole systems
• Measuring Black Hole Spin using X-ray Reflection Spectroscopy
• Probes and Tests of Strong-Field Gravity with Observations in the Electromagnetic Spectrum
• Black Hole Spin via Continuum Fitting and the Role of Spin in Powering Transient Jets
• Broad emission lines for negatively spinning black holes
• The enhanced X-ray Timing and Polarimetry mission - eXTP
• Testing black hole candidates with electromagnetic radiation
• Magnetic Stress at the Marginally Stable Orbit: Altered Disk Structure, Radiation, and Black Hole Spin Evolution
• Observational Constraints on Black Hole Spin
• General parametrization of axisymmetric black holes in metric theories of gravity
• An extended scheme for fitting X-ray data with accretion disk spectra in the strong gravity regime
• Understanding X-ray reflection emissivity profiles in AGN: Locating the X-ray source
• Iron fluorescence from within the innermost stable orbit of black hole accretion disks
• Global MHD Simulation of the Inner Accretion Disk in a Pseudo-Newtonian Potential
• Testing the No-Hair Theorem with Event Horizon Telescope Observations of Sagittarius A*
• Charged Rotating Black Holes on a 3-Brane
• Black Hole Based Tests of General Relativity
• The lack of variability of the iron line in MCG-6-30-15: general relativistic effects
• Relativistic Lines and Reflection from the Inner Accretion Disks Around Neutron Stars
• Extreme Gravitational Lensing near Rotating Black Holes
• Testing the No-Hair Theorem with Observations in the Electromagnetic Spectrum. IV. Relativistically Broadened Iron Lines
• FERO: Finding Extreme Relativistic Objects. I. Statistics of Relativistic Fe Kalpha lines in Radio-Quiet Type 1 AGN
• Astrophysical Violations of the Kerr Bound as a Possible Signature of String Theory
• Testing the Kerr black hole hypothesis
• Effects of Kerr Spacetime on Spectral Features from X-Ray Illuminated Accretion Discs
• Fast variability from black-hole binaries
• Iron Line Profiles in Strong Gravity
• Relativistic Iron Line Emission from the Neutron Star Low-mass X-ray Binary 4U 1636-536
• On Relativistic Disk Spectroscopy in Compact Objects with X-ray CCD Cameras
• Simulations of accretion flows crossing the last stable orbit
• GRO J1655-40: Early Stages of the 2005 Outburst
• XMM-Newton and INTEGRAL spectroscopy of the microquasar GRO J1655-40 during its 2005 outburst
• Testing the Kerr metric with the iron line and the KRZ parametrization
• Low/Hard State Spectra of GRO J1655-40 Observed with Suzaku
• Venturing beyond the ISCO: Detecting X-ray emission from the plunging regions around black holes
• Event horizon image within black hole shadow
• Steep X-ray reflection emissivity profiles in AGN as the result of radially-structured disc ionisation
• Black hole spin: theory and observation
• Wind, jet, hybrid corona and hard X-ray flares: multiwavelength evolution of GRO J1655-40 during the 2005 outburst rise
• The high energy emission of GRO J1655-40 as revealed with INTEGRAL spectroscopy of the 2005 outburst
• Modeling uncertainties in X-ray reflection spectroscopy measurements I: Impact of higher order disk images
• Discovery of a red and blue shifted iron disk line in the galactic jet source GRO J1655-40
• Imaging black holes: past, present and future
• What is the closest black hole to the Sun?
• The lamppost model: effects of photon trapping, the bottom lamp and disc truncation
• Twin peak HF QPOs as a spectral imprint of dual oscillation modes of accretion tori
• Relativistic reflection spectra of super-spinning black holes
• The Athena X-ray Integral Field Unit
• A note on some discrepancies in convolution models in X-ray spectral analysis

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