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arXiv · 1212.4149

Constraining the Accretion Flow in Sgr A* by General Relativistic Dynamical and Polarized Radiative Modeling

Roman V. Shcherbakov·Robert F. Penna·Jonathan C. McKinney
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Abstract

We briefly summarize the method of simulating Sgr A* polarized sub-mm spectra from the accretion flow and fitting the observed spectrum. The dynamical flow model is based on three-dimensional general relativistic magneto hydrodynamic simulations. Fully self-consistent radiative transfer of polarized cyclo-synchrotron emission is performed. We compile a mean sub-mm spectrum of Sgr A* and fit it with the mean simulated spectra. We estimate the ranges of inclination angle theta=42-75deg, mass accretion rate Mdot=(1.4-7.0)*10^{-8}Msun/yr, and electron temperature Te=(3-4)*10^{10}K at 6M. We discuss multiple caveats in dynamical modeling, which must be resolved to make further progress.

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Roman V. Shcherbakov, Robert F. Penna, Jonathan C. McKinney. 2012-12-17. Constraining the Accretion Flow in Sgr A* by General Relativistic Dynamical and Polarized Radiative Modeling. https://doi.org/10.1017/s1743921312020157

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