Observational Constraints on Direct Electron Heating in the Hot Accretion Flows in Sgr A* and M87*
arXiv:2210.02879 · doi:10.3847/1538-4357/aca534
Abstract
An important parameter in the theory of hot accretion flows around black holes is , which describes the fraction of ``viscously'' dissipated energy in the accretion flow that goes directly into heating electrons. For a given mass accretion rate, the radiative efficiency of a hot accretion flow is determined by . Unfortunately, the value of is hard to determine from first principles. The recent Event Horizon Telescope Collaboration (EHTC) results on M87* and Sgr A* provide us with a different way of constraining . By combining the mass accretion rates in M87* and Sgr A* estimated by the EHTC with the measured bolometric luminosities of the two sources, we derive good constraints on the radiative efficiencies of the respective accretion flows. In parallel, we use a theoretical model of hot magnetically arrested disks (MAD) to calculate the expected radiative efficiency as a function of (and accretion rate). By comparing the EHTC-derived radiative efficiencies with the theoretical results from MAD models, we find that Sgr A* requires $δ\ga 0.3$. %with the most likely value being . A similar comparison in the case of M87* gives inconclusive results as there is still a large uncertainty in the accretion rate in this source.
arXiv comment9 pages, 2 figures. To appear in ApJ
References in corpus (69)
- X-ray Properties of Black-Hole Binaries
- Advection-Dominated Accretion: A Self-Similar Solution
- First M87 Event Horizon Telescope Results. VI. The Shadow and Mass of the Central Black Hole
- Advection-Dominated Accretion: Underfed Black Holes and Neutron Stars
- Hot Accretion Flows Around Black Holes
- Advection-Dominated Accretion and the Spectral States of Black Hole X-Ray Binaries: Application to Nova Muscae 1991
- Modelling the behaviour of accretion flows in X-ray binaries
- Efficient Generation of Jets from Magnetically Arrested Accretion on a Rapidly Spinning Black Hole
- Nuclear Activity in Nearby Galaxies
- General Relativistic Magnetohydrodynamic Simulations of Magnetically Choked Accretion Flows around Black Holes
- Magnetically Arrested Disk: An Energetically Efficient Accretion Flow
- Nonthermal Electrons in Radiatively Inefficient Accretion Flow Models of Sagittarius A*
- First M87 Event Horizon Telescope Results. VIII. Magnetic Field Structure near The Event Horizon
- First Sagittarius A* Event Horizon Telescope Results. VI: Testing the Black Hole Metric
- Thermal Equilibria of Accretion Disks
- First Sagittarius A* Event Horizon Telescope Results. V. Testing Astrophysical Models of the Galactic Center Black Hole
- Black Hole Spin and the Radio Loud/Quiet Dichotomy of Active Galactic Nuclei
- Three-dimensional MHD Simulations of Radiatively Inefficient Accretion Flows
- GRMHD Simulations of Magnetized Advection Dominated Accretion on a Non-Spinning Black Hole: Role of Outflows
- The Black-Hole Mass in M87 from Gemini/NIFS Adaptive Optics Observations
- The power of relativistic jets is larger than the luminosity of their accretion disks
- A Global Spectral Study of Black Hole X-ray Binaries
- Numerical Simulation of Hot Accretion Flows (II): Nature, Origin, and Properties of Outflow and Their Possible Observational Applications
- Interferometric Detection of Linear Polarization from Sagittarius A* at 230 GHz
- Magnetohydrodynamical Non-radiative Accretion Flows in Two-Dimensions
- Numerical Simulation of Hot Accretion Flows (III): Revisiting wind properties using trajectory approach
- Turbulence and Particle Heating in Advection-Dominated Accretion Flows
- Particle Heating by Alfvenic Turbulence in Hot Accretion Flows
- Electron Heating in Hot Accretion Flows
- Constraining the Accretion Rate Onto Sagittarius A* Using Linear Polarization
- The Radiative Efficiency of Hot Accretion Flows
- Jets in Magnetically Arrested Hot Accretion Flows: Geometry, Power and Black Hole Spindown
- A prescription for the turbulent heating of astrophysical plasmas
- Large-Scale Poloidal Magnetic Field Dynamo Leads to Powerful Jets in GRMHD Simulations of Black Hole Accretion with Toroidal Field
- Electron and Proton Acceleration in Trans-Relativistic Magnetic Reconnection: Dependence on Plasma Beta and Magnetization
- The central parsecs of M87: jet emission and an elusive accretion disc
- Stochastic Particle Acceleration in Multiple Magnetic Islands during Reconnection
- Magnetohydrodynamic Simulations of Active Galactic Nucleus Disks and Jets
- Influence of Ohmic Heating on Advection-Dominated Accretion Flows
- Measuring Mass Accretion Rate onto the Supermassive Black Hole in M 87 Using Faraday Rotation Measure with the Submillimeter Array
- Luminous hot accretion disks
- Electron and proton heating in trans-relativistic magnetic reconnection
- Are Particles in Advection-Dominated Accretion Flows Thermal?
- Sgr A* Polarization: No ADAF, Low Accretion Rate, and Non-Thermal Synchrotron Emission
- Variability Timescale and Spectral Index of Sgr A* in the Near Infrared: Approximate Bayesian Computation Analysis of the Variability of the Closest Supermassive Black Hole
- Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign
- State-of-the-art energetic and morphological modelling of the launching site of the M87 jet
- Core shifts, magnetic fields and magnetization of extragalactic jets
- Electron Heating by the Ion Cyclotron Instability in Collisionless Accretion Flows. I. Compression-Driven Instabilities and the Electron Heating Mechanism
- What really makes an accretion disc MAD
- Flux eruption events drive angular momentum transport in magnetically arrested accretion flows
- The Radiative Efficiency and Spectra of Slowly Accreting Black Holes from Two-Temperature GRRMHD Simulations
- Particle Acceleration during Magnetorotational Instability in a Collisionless Accretion Disk
- The Heating of Test Particles in Numerical Simulations of Alfvenic Turbulence
- Ion and electron heating during magnetic reconnection in weakly collisional plasmas
- A Resolution Study of Magnetically Arrested Disks
- ALMA Observations of the Terahertz Spectrum of Sagittarius A*
- The Accretion flow in M87 is really MAD
- Electron and Proton Heating in Transrelativistic Guide Field Reconnection
- Numerical simulation of hot accretion flows (IV): effects of black hole spin and magnetic field strength on the wind and the comparison between wind and jet properties
- Electron Heating in Low Mach Number Perpendicular shocks. I. Heating Mechanism
- A Detection of Sgr A* in the far infrared
- Observational Signatures of Frame Dragging in Strong Gravity
- Electron Heating in Low Mach Number Perpendicular shocks. II. Dependence on the Pre-Shock Conditions
- Towards Self-Consistent Modelling of the Sgr A* Accretion Flow: Linking Theory and Observation
- Electron heating and acceleration by magnetic reconnection in hot accretion flows
- Radiative Properties of Magnetically-Arrested Disks
- Particle Heating by Nonlinear Alfvenic Turbulence in ADAFs
- Monte Carlo simulations of global Compton cooling in inner regions of hot accretion flows