What is the Accretion Rate in Sgr A*?

Abstract

The radio source Sgr A* at the center of our Galaxy is believed to be a 2.6 x 10^6 solar mass black hole which accretes gas from the winds of nearby stars. We show that limits on the X-ray and infrared emission from the Galactic Center provide an upper limit of ~ 8 x 10^{-5} solar masses per year on the mass accretion rate in Sgr A*. The advection-dominated accretion flow (ADAF) model favors a rate < 10^{-5} solar masses per year. In comparison, the Bondi accretion rate onto Sgr A*, estimated using the observed spatial distribution of mass losing stars and assuming non-interacting stellar winds, is ~ 3 x 10^{-5} solar masses per year. There is thus rough agreement between the Bondi, the ADAF, and the X-ray inferred accretion rates for Sgr A*. We discuss uncertainties in these estimates, emphasizing the importance of upcoming observations by the Chandra X-ray observatory (CXO) for tightening the X-ray derived limits.

to appear in ApJ Letters

Cited by in corpus (56)

• Testing the nature of dark compact objects: a status report
• Chandra X-ray Spectroscopic Imaging of Sgr A* and the Central Parsec of the Galaxy
• Can environmental effects spoil precision gravitational-wave astrophysics?
• An extreme magneto-ionic environment associated with the fast radio burst source FRB 121102
• The Supermassive Black Hole at the Galactic Center
• Dissecting X-ray-emitting Gas around the Center of our Galaxy
• The Dynamical Structure of Nonradiative Black Hole Accretion Flows
• New Evidence for Black Hole Event Horizons from Chandra
• Spectral energy distributions of selfgravitating QSO discs
• A refined sub-grid model for black hole accretion and AGN feedback in large cosmological simulations
• Phenomenological aspects of black holes beyond general relativity
• Constraining the Accretion Rate Onto Sagittarius A* Using Linear Polarization
• A Dynamical Model for Hot Gas in the Galactic Center
• Chandra Limits on X-ray Emission Associated with the Supermassive Black Holes in Three Giant Elliptical Galaxies
• Sgr A* Polarization: No ADAF, Low Accretion Rate, and Non-Thermal Synchrotron Emission
• Unprecedented variability of Sgr A* in NIR
• Dynamics of galaxy cores and supermassive black holes
• Structure of Sagittarius A* at 86 GHz using VLBI Closure Quantities
• Variable Linear Polarization from Sagittarius A*: Evidence for a Hot Turbulent Accretion Flow
• X-ray bubbles in the circumgalactic medium of TNG50 Milky Way- and M31-like galaxies: signposts of supermassive black hole activity
• ALMA Polarimetry of Sgr A*: Probing the Accretion Flow from the Event Horizon to the Bondi Radius
• The Fate of Non-Radiative Magnetized Accretion Flows: Magnetically-Frustrated Convection
• Star formation in accretion discs : from the Galactic Center to Active Galactic Nuclei
• Sub-parsec supermassive Binary Quasars: expectations at z<1
• Evolving Nonthermal Electrons in Simulations of Black Hole Accretion
• Direct Feeding of the Black Hole at the Galactic Center with Radial Gas Streams from Close-In Stellar Winds
• The Linear Polarization of Sagittarius A* II. VLA and BIMA Polarimetry at 22, 43 and 86 GHz
• 15-GHz radio emission from nearby low-luminosity active galactic nuclei
• Radio light curves during the passage of cloud G2 near Sgr A*
• A Radio Transient 0.1 pc from Sagittarius A*
• The Radio Galaxy Population in the SIMBA SImulations
• The role of the outer boundary condition in accretion disk models: theory and application
• Positron Effects on Polarized Images and Spectra from Jet and Accretion Flow Models of M87* and Sgr A*
• Properties of the Radio-Emitting Gas Around SgrA*
• Nonaxisymmetric Effects in the Black Hole Accretion Inviscid Hydrodynamics: Formation and Evolution of a Tilted Torus
• Capture of a Red Giant by the Black Hole Sagittarius A* as a Possible Origin for the TeV Gamma Rays from the Galactic Center
• Massive black holes in stellar systems: 'quiescent' accretion and luminosity
• Synchrotron Afterglow Model for AT 2022cmc: Jetted Tidal Disruption Event or Engine-Powered Supernova?
• X-ray Line Diagnostics of Hot Accretion Flows around Black Holes
• Can MAD accretion disks launching structured jets explain both GRB and AGN engines? Magnetically arrested accretion disks launching structured jets in application to GRB and AGN engines
• Testing the Dark Matter Annihilation Model for the WMAP Haze
• Multi-Frequency Models of Black Hole Photon Rings from Low-Luminosity Accretion Disks
• Rapid Growth of Galactic Supermassive Black Holes through Accreting Giant Molecular Clouds during Major Mergers of their Host Galaxies
• Predictions of the pseudo-complex theory of Gravity for EHT observations- II. Theory and predictions
• The environments of the radio galaxy population in SIMBA
• The Stellar Winds of Galactic Centre and the Low Accretion Rate of Sgr A*
• Point mass Cosmological Black Holes
• Simulating the pericentre passage of the Galactic centre star S2
• Jet Launching Radius in Low-Power Radio-Loud AGNs in Advection-Dominated Accretion Flows
• Radio Variability of the Sagittarius ${\mathrm{A}}^{\ast }$ due to an Orbiting Star
• Mass flows in the Galactic Center by supernovae of the circumnuclear disk
• The gas streamer G1-2-3 in the Galactic Center
• Deciphering signatures of Kerr-Sen black holes in presence of plasma from the Event Horizon Telescope data
• Investigating the interplay of the braneworld gravity and the plasma environment on the black hole shadow
• Searching for Isolated Black Hole Candidates within 15 pc of the Solar System in Gaia DR3
• Remarks on Dark Matter Constituents with Many Solar Masses