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arXiv · 1107.2923

Can a Satellite Galaxy Merger Explain the Active Past of the Galactic Center?

Meagan Lang·Kelly Holley-Bockelmann·Tamara Bogdanovic·Pau Amaro-Seoane·Alberto Sesana·Manodeep Sinha
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Abstract

Observations of the Galactic Center (GC) have accumulated a multitude of "forensic" evidence indicating that several million years ago the center of the Milky Way galaxy was teaming with starforming and accretion-powered activity -- this paints a rather different picture from the GC as we understand it today. We examine a possibility that this epoch of activity could have been triggered by the infall of a satellite galaxy into the Milky Way which began at the redshift of 10 and ended few million years ago with a merger of the Galactic supermassive black hole with an intermediate mass black hole brought in by the inspiralling satellite.

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Meagan Lang, Kelly Holley-Bockelmann, Tamara Bogdanovic, Pau Amaro-Seoane, Alberto Sesana, Manodeep Sinha. 2011-07-14. Can a Satellite Galaxy Merger Explain the Active Past of the Galactic Center?. https://doi.org/10.1093/mnras%2Fsts638

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