Polarized Emission of Sagittarius A*

Abstract

We explore the parameter space of the two temperature pseudo-Newtonian Keplerian accretion flow model for the millimeter and shorter wavelength emission from Sagittarius A*. A general relativistic ray-tracing code is used to treat the radiative transfer of polarized synchrotron emission from the flow. The synchrotron self-Comptonization and bremsstrahlung emission components are also included. It is shown that the model can readily account for the millimeter to sub-millimeter emission characteristics with an accretion rate of ~6x10^17g.s^-1 and an inclination angle of ~40 deg. However, the corresponding model predicted near-infrared and X-ray fluxes are more than one order of magnitude lower than the observed 'quiescent' state values. While the extended quiescent-state X-ray emission has been attributed to thermal emission from the large-scale accretion flow, the NIR emission and flares are likely dominated by emission regions either within the last stable orbit of a Schwarzschild black hole or associated with outflows. With the viscous parameter derived from numerical simulations, there is still a degeneracy between the electron heating rate and the magnetic parameter. A fully general relativistic treatment with the black hole spin incorporated will resolve these issues.

27 pages, 6 figures, ApJ accepted

References in corpus (15)

• Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
• An Unambiguous Detection of Faraday Rotation in Sagittarius A*
• Polarimetry of near-infrared flares from Sagittarius A*
• Simulating the Emission and Outflows from Accretion Disks
• X-ray hiccups from SgrA* observed by XMM-Newton. The second brightest flare and three moderate flares caught in half a day
• Polarized NIR and X-ray Flares from SgrA*
• The Rotation Measure and 3.5mm Polarization of Sgr A*
• Black Hole Shadow Image and Visibility Analysis of Sagittarius A*
• On the orientation of the Sagittarius A* system
• A Local Model for Angular Momentum Transport in Accretion Disks Driven by the Magnetorotational Instability
• Propagation Effects in Magnetized Transrelativistic Plasmas
• The Variability of Polarized Radiation from Sgr A*
• Linearly and Circularly Polarized Emission in Sagittarius A*
• The Nature of Linearly Polarized Millimeter and Sub-millimeter Emission in Sagittarius A*
• Modulated X-ray Emissivity near the Stress Edge in Sgr A*

Cited by in corpus (21)

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• A public code for general relativistic, polarised radiative transfer around spinning black holes
• Sagittarius A* Accretion Flow and Black Hole Parameters from General Relativistic Dynamical and Polarized Radiative Modeling
• Tilted black hole accretion disc models of Sagittarius A*: time-variable millimetre to near-infrared emission
• A geometric crescent model for black hole images
• A Monte Carlo Code for Relativistic Radiation Transport Around Kerr Black Holes
• General relativistic polarized radiative transfer: building a dynamics-observations interface
• ALMA Observations of the Terahertz Spectrum of Sagittarius A*
• The Circular Polarization of Sagittarius A* at Submillimeter Wavelengths
• Detecting Changing Polarization Structures in Sagittarius A* with High Frequency VLBI
• Faraday Conversion and Rotation In Uniformly Magnetized Relativistic Plasmas
• Probing the innermost accretion flow geometry of Sgr A* with Event Horizon Telescope
• Spectral and Imaging properties of Sgr A* from High-Resolution 3D GRMHD Simulations with Radiative Cooling
• Testing the Accretion Flow with Plasma Wave Heating Mechanism for Sagittarius a* by the 1.3MM Vlbi Measurements
• Linearly Polarized Millimeter and Submillimeter Continuum Emission of Sgr A* Constrained by ALMA
• The 492 GHz emission of Sgr A* constrained by ALMA
• Constraining the Flaring Region of Sagittarius A* By 1.3mm VLBI Measurements
• Impact of the nonthermal electron radiation effects on the horizon scale image structure of Sagittarius A*
• Constraining the Accretion Flow in Sgr A* by General Relativistic Dynamical and Polarized Radiative Modeling
• Secondary CMB anisotropies from magnetized halos --I: Power spectra of the Faraday rotation angle and conversion rate