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arXiv · 1908.00549

A common origin for the circumnuclear disc and the nearby molecular clouds in the Galactic Centre

Alessandro Ballone·Michela Mapelli·Alessandro Alberto Trani
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Abstract

The origin of the molecular clouds orbiting SgrA* is one of the most debated questions about our Galactic Centre. Here, we present the hydrodynamic simulation of a molecular cloud infalling towards SgrA*, performed with the adaptive-mesh-refinement code RAMSES. Through such simulation, we propose that the circumnuclear disc and the +20 km/s cloud originated from the same tidal disruption episode, occurred less than 1 Myr ago. We also show that recent star formation is to be expected in the +20 km/s cloud, as also suggested by recent observations.

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Alessandro Ballone, Michela Mapelli, Alessandro Alberto Trani. 2019-08-01. A common origin for the circumnuclear disc and the nearby molecular clouds in the Galactic Centre. https://doi.org/10.1093/mnras/stz2147

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