Testing RIAF model for Sgr A* using the size measurements

Abstract

Recent radio observations by the VLBA at 7 and 3.5 mm produced the high-resolution images of the compact radio source located at the center of our Galaxy--Sgr A*, and detected its wavelength-dependent intrinsic sizes at the two wavelengths. This provides us with a good chance of testing previously-proposed theoretical models for Sgr A*. In this {\em Letter}, we calculate the size based on the radiatively inefficient accretion flow (RIAF) model proposed by Yuan, Quataert & Narayan (2003). We find that the predicted sizes after taking into account the scattering of the interstellar electrons are consistent with the observations. We further predict an image of Sgr A* at 1.3 mm which can be tested by future observations.

10 pages, 1 figure; accepted by ApJL

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Cited by in corpus (28)

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• Gravitational Lensing by Black Holes
• Evidence for X-ray synchrotron emission from simultaneous mid-IR to X-ray observations of a strong Sgr A* flare
• The Intrinsic Size of Sagittarius A* from 0.35 cm to 6 cm
• Spectral Models for Low-luminosity Active Galactic Nuclei in LINERs: The Role of Advection-dominated Accretion and Jets
• Towards the event horizon -- the supermassive black hole in the Galactic Center
• How to hide large scale outflows: size constraints on the jets of Sgr A*
• On the origin of X-ray emission in some FR Is: ADAF or jet?
• Hot Accretion With Conduction: Spontaneous Thermal Outflows
• Spectral Energy Distribution of the inner accretion flow around Sgr A* -- Clue for a weak outflow in the innermost region
• Images of the radiatively inefficient accretion flow surrounding a Kerr black hole: application in Sgr A*
• Evidence for Rapidly Rotating Black Holes in FR I Radio Galaxies
• Possible Origin of Radio Emission from Nonthermal Electrons in Hot Accretion Flows for Low-Luminosity Active Galactic Nuclei
• The Intrinsic Shape of Sagittarius A* at 3.5-mm Wavelength
• A time-dependent jet model for the emission from Sagittarius A*
• Iron line profiles and self-shadowing from relativistic thick accretion discs
• Properties of the Radio-Emitting Gas Around SgrA*
• An accretion-jet model for M87: interpreting the spectral energy distribution and Faraday rotation measure
• Monte Carlo simulations of global Compton cooling in inner regions of hot accretion flows
• Nonthermal processes in hot accretion flows onto supermassive black holes: An inhomogeneous model
• The multiwavelength spectrum of NGC 3115: Hot accretion flow properties
• Accretion models of Sgr A*
• Radio emission and jets from microquasars
• Confronting the jet model of Sgr A* with the Faraday rotation measure observations
• High-resolution Millimeter-VLBI Imaging of Sgr A*
• High-frequency VLBI observations of SgrA* during a multi-frequency campaign in May 2007
• The Galactic Center Black Hole Laboratory
• Origin of the X-ray Emission in the Nuclei of FR Is