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