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arXiv · 1201.3536

What's in a Fermi Bubble: a quasar episode in the Galactic centre

Kastytis Zubovas·Sergei Nayakshin·Andrew King
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Abstract

Fermi bubbles, the recently observed giant (~10 kpc high) gamma-ray emitting lobes on either side of our Galaxy (Su et al. 2010), appear morphologically connected to the Galactic center, and thus offer a chance to test several models of supermassive black hole (SMBH) evolution, feedback and relation with their host galaxies. We use a physical feedback model (King 2003, 2010) and novel numerical techniques (Nayakshin et al. 2009) to simulate a short burst of activity in Sgr A*, the central SMBH of the Milky Way, ~6 Myr ago, temporally coincident with a star formation event in the central parsec. We are able to reproduce the bubble morphology and energetics both analytically (Zubovas et al. 2011) and numerically (Zubovas & Nayakshin, in prep). These results provide strong support to the model, which was also used to simulate more extreme environments (Nayakshin & Power 2010).

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Kastytis Zubovas, Sergei Nayakshin, Andrew King. 2012-01-17. What's in a Fermi Bubble: a quasar episode in the Galactic centre. https://arxiv.org/abs/1201.3536

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