A geometric crescent model for black hole images

Abstract

The Event Horizon Telescope (EHT), a global very long baseline interferometry array operating at millimetre wavelengths, is spatially resolving the immediate environments of black holes for the first time. The current observations of the Galactic center black hole, Sagittarius A* (Sgr A*), and M87 have been interpreted in terms of either geometric models (e.g., a symmetric Gaussian) or detailed calculations of the appearance of black hole accretion flows. The former are not physically motivated, while the latter are subject to large systematic uncertainties. Motivated by the dominant relativistic effects of Doppler beaming and gravitational lensing in many calculations, we propose a geometric crescent model for black hole images. We show that this simple model provides an excellent statistical description of the existing EHT data of Sgr A* and M87, superior to other geometric models for Sgr A*. It also qualitatively matches physically predicted models, bridging accretion theory and observation. Based on our results, we make predictions for the detectability of the black hole shadow, a signature of strong gravity, in future observations.

8 pages, 9 figures, MNRAS, in press

References in corpus (11)

• emcee: The MCMC Hammer
• General Relativistic Magnetohydrodynamic Simulations of Magnetically Choked Accretion Flows around Black Holes
• Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
• Jet Launching Structure Resolved Near the Supermassive Black Hole in M87
• Global General Relativistic MHD Simulation of a Tilted Black-Hole Accretion Disk
• The Submillimeter Bump in Sgr A* from Relativistic MHD Simulations
• Galactic Centre stellar winds and Sgr A* accretion
• Simulating the Emission and Outflows from Accretion Disks
• Tilted black hole accretion disc models of Sagittarius A*: time-variable millimetre to near-infrared emission
• Using Millimeter VLBI to Constrain RIAF Models of Sagittarius A*
• Modelling the black hole silhouette in Sgr A* with ion tori

Cited by in corpus (45)

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First M87 Event Horizon Telescope Results. VI. The Shadow and Mass of the Central Black Hole
• Shadows of spherically symmetric black holes and naked singularities
• Photon Rings around Kerr and Kerr-like Black Holes
• A coordinate-independent characterization of a black hole shadow
• Testing General Relativity with the Event Horizon Telescope
• Observational appearance of inefficient accretion flows and jets in 3D GRMHD simulations: Application to Sgr~A*
• Sgr A* and General Relativity
• Towards the event horizon -- the supermassive black hole in the Galactic Center
• An 8 hour characteristic time-scale in submillimetre light curves of Sagittarius A*
• Persistent Asymmetric Structure of Sagittarius A* on Event Horizon Scales
• Detection of intrinsic source structure at ~3 Schwarzschild radii with Millimeter-VLBI observations of SAGITTARIUS A*
• The Event Horizon Telescope: exploring strong gravity and accretion physics
• A parameter survey of Sgr A* radiative models from GRMHD simulations with self-consistent electron heating
• Strong field gravitational lensing by a charged Galileon black hole
• Monitoring the Morphology of M87* in 2009-2017 with the Event Horizon Telescope
• The impact of Faraday effects on polarized black hole images of Sagittarius A*
• Probing the innermost accretion flow geometry of Sgr A* with Event Horizon Telescope
• Simulations of M87 and Sgr A* Imaging with the Millimetron Space Observatory on near-Earth orbits
• Silhouettes of invisible black holes
• Selective Dynamical Imaging of Interferometric Data
• On the approximation of the black hole shadow with a simple polar curve
• Event horizon image within black hole shadow
• The Galactic Center as a laboratory for theories of gravity and dark matter
• GRMHD simulations of visibility amplitude variability for Event Horizon Telescope images of Sgr A*
• To see invisible: image of the event horizon within the black hole shadow
• Event horizon silhouette: implications to supermassive black holes M87* and SgrA*
• Distinguishing an ejected blob from alternative flare models at the Galactic centre with GRAVITY
• No asymmetric outflows from Sagittarius A* during the pericenter passage of the gas cloud G2
• Probing spacetime around Sagittarius A* using modeled VLBI closure phases
• MeqSilhouette v2: Spectrally-resolved polarimetric synthetic data generation for the Event Horizon Telescope
• Principal-Component Interferometric Modeling (PRIMO), an Algorithm for EHT Data I: Reconstructing Images from Simulated EHT Observations
• Polarimetric Geometric Modeling for mm-VLBI Observations of Black Holes
• Reconstruction of Static Black Hole Images Using Simple Geometric Forms
• SYMBA: An end-to-end VLBI synthetic data generation pipeline
• Impact of the nonthermal electron radiation effects on the horizon scale image structure of Sagittarius A*
• Neural Network Astronomy as a New Tool for Observing Bright and Compact Objects
• Model Predictions of the Results of Interferometric Observations for Stars under Conditions of Strong Gravitational Scattering by Black Holes and Wormholes
• A proof-of-concept neural network for inferring parameters of a black hole from partial interferometric images of its shadow
• GALLIFRAY -- A geometric modeling and parameter estimation framework for black hole images using bayesian techniques
• Detecting Black Hole Occultations by Stars with Space Interferometric Telescopes
• Visible shapes of black holes M87* and SgrA*
• High Resolution Imaging of a Black Hole Shadow with Millimetron Orbit around Lagrange Point L2
• Beyond Sgr A* and M87*: Sub-Microarcsecond Black Hole Shadow Detection via Lunar-based Extremely Long Baseline Interferometry
• The Nature of Black Hole Shadows