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Testing RIAF model for Sgr A* using the size measurements

Feng Yuan·Zhi-Qiang Shen·Lei Huang
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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.

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Feng Yuan, Zhi-Qiang Shen, Lei Huang. 2006-03-24. Testing RIAF model for Sgr A* using the size measurements. https://doi.org/10.1086/504475

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