Reconciling EHT and Gas Dynamics Measurements in M87: Is the Jet Misaligned at Parsec Scales?

Abstract

The Event Horizon Telescope mass estimate for M87* is consistent with the stellar dynamics mass estimate, and inconsistent with the gas dynamics mass estimates by up to $2\sigma$. We have previously explored a new gas dynamics model that incorporated sub-Keplerian gas velocities that could in principle explain the discrepancy in the stellar and gas dynamics mass estimate. In this paper, we extend this gas dynamical model to also include non-trivial disk heights, which may also resolve the mass discrepancy independent of sub-Keplerian velocity components. By combining the existing velocity measurements and the EHT mass estimate, we place constraints on the gas disk inclination and sub-Kelplerian fraction. These constraints require the parsec-scale ionized gas disk be misaligned with the milli-arcsecond radio jet by at least $11^{\circ }$, and more typically $27^{\circ }$. Modifications to the gas dynamics model either by introducing sub-Keplerian velocities or thick disks produces further misalignment with the radio jet. If the jet is produced in a Blandford-Znajek-type process, the angular momentum of the black hole is decoupled with the angular momentum of the large scale gas feeding M87*.

6 pages, 4 figures. Published in the Astrophysical Journal Feb. 19 2021

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Cited by in corpus (8)

• The Photon Ring in M87*
• Separating Astrophysics and Geometry in Black Hole Images
• Disc tearing: numerical investigation of warped disc instability
• Supermassive black hole mass in the massive elliptical galaxy M87 from integral-field stellar dynamics using OASIS and MUSE with adaptive optics: assessing systematic uncertainties
• M87: a cosmic laboratory for deciphering black hole accretion and jet formation
• Bayesian Black Hole Photogrammetry
• WISDOM project -- XVIII. Molecular gas distributions and kinematics of three megamaser galaxies
• Assessing the Role of Intrinsic Variability in Black Hole Parameter Inference using Multi-Epoch EHT Data