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The Structure and Variability of Sagittarius A*: Zooming in to the Supermassive Black Hole at the Galactic Center

Feng Yuan·Jun-Hui Zhao
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Abstract

The Galactic center provides a unique astrophysical laboratory for us to study various astrophysical processes. In this paper, we review and outline the latest results from observations of Sgr~A$^*$ in terms of source structure and variations in flux density. Sgr~A$^*$ phenomenon represents a typical case of low radiative efficiency accretion flow surrounding a supermassive black hole in low luminosity AGNs. Many pending astrophysical problems found from observations of Sgr A$^*$ have challenged the existing astrophysical theories. Current theoretical models of Sgr A$^*$ are also reviewed.

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Feng Yuan, Jun-Hui Zhao. 2002-03-04. The Structure and Variability of Sagittarius A*: Zooming in to the Supermassive Black Hole at the Galactic Center. https://arxiv.org/abs/astro-ph/0203050

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