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arXiv · 1210.3034

Traces of past activity in the Galactic Centre

Gabriele Ponti·Mark R. Morris·Regis Terrier·Andrea Goldwurm
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Abstract

The Milky Way centre hosts a supermassive Black Hole (BH) with a mass of ~4*10^6 M_Sun. Sgr A*, its electromagnetic counterpart, currently appears as an extremely weak source with a luminosity L~10^-9 L_Edd. The lowest known Eddington ratio BH. However, it was not always so; traces of "glorious" active periods can be found in the surrounding medium. We review here our current view of the X-ray emission from the Galactic Center (GC) and its environment, and the expected signatures (e.g. X-ray reflection) of a past flare. We discuss the history of Sgr A*'s past activity and its impact on the surrounding medium. The structure of the Central Molecular Zone (CMZ) has not changed significantly since the last active phase of Sgr A*. This relic torus provides us with the opportunity to image the structure of an AGN torus in exquisite detail.

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Gabriele Ponti, Mark R. Morris, Regis Terrier, Andrea Goldwurm. 2012-10-10. Traces of past activity in the Galactic Centre. https://doi.org/10.1007/978-3-642-35410-6_26

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