Testing General Relativity with Accretion-Flow Imaging of Sgr A*

Abstract

The Event Horizon Telescope is a global very-long baseline interferometer capable of probing potential deviations from the Kerr metric, which is believed to provide the unique description of astrophysical black holes. Here we report an updated constraint on the quadrupolar deviation of Sagittarius A* within the context of a radiatively inefficient accretion flow model in a quasi-Kerr background. We also simulate near-future constraints obtainable by the forthcoming eight-station array and show that in this model already a one-day observation can measure the spin magnitude to within $0.005$, the inclination to within $0.09^{\circ }$, the position angle to within $0.04^{\circ }$, and the quadrupolar deviation to within $0.005$ at $3\sigma$ confidence. Thus, we are entering an era of high-precision strong gravity measurements.

5+1 pages, 3 figures

References in corpus (11)

• The Confrontation between General Relativity and Experiment
• 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
• A Metric for Rapidly Spinning Black Holes Suitable for Strong-Field Tests of the No-Hair Theorem
• Testing the general relativistic ''no-hair'' theorems using the galactic center black hole SgrA*
• The old nuclear star cluster in the Milky Way: dynamics, mass, statistical parallax, and black hole mass
• Bumpy Black Holes in Alternate Theories of Gravity
• A code to compute the emission of thin accretion disks in non-Kerr space-times and test the nature of black hole candidates
• Testing the space-time geometry around black hole candidates with the analysis of the broad K$\alpha$ iron line
• Imaging the Supermassive Black Hole Shadow and Jet Base of M87 with the Event Horizon Telescope
• Imaging an Event Horizon: Mitigation of Scattering Toward Sagittarius A*

Cited by in corpus (7)

• Spontaneously scalarised Kerr black holes
• Testing General Relativity with stellar orbits around the supermassive black hole in our Galactic center
• Shadows of Einstein-dilaton-Gauss-Bonnet black holes
• Radio observations of active galactic nuclei with mm-VLBI
• Event horizon silhouette: implications to supermassive black holes M87* and SgrA*
• Can accretion properties distinguish between a naked singularity, wormhole and black hole?
• Testing Ghasemi-Nodehi-Bambi metric parameters with quasi-periodic oscillations