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arXiv · 1809.01664

Weighing the IMBH candidate CO-0.40-0.22* in the Galactic Centre

Alessandro Ballone·Michela Mapelli·Mario Pasquato
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Abstract

The high velocity gradient observed in the compact cloud CO-0.40-0.22, at a projected distance of 60 pc from the centre of the Milky Way, has led its discoverers to identify the closeby mm continuum emitter, CO-0.40-0.22*, with an intermediate mass black hole (IMBH) candidate. We describe the interaction between CO-0.40-0.22 and the IMBH, by means of a simple analytical model and of hydrodynamical simulations. Through such calculation, we obtain a lower limit to the mass of CO-0.40-0.22* of few $10^4 \times \; M_{\odot}$. This result tends to exclude the formation of such massive black hole in the proximity of the Galactic Centre. On the other hand, CO-0.40-0.22* might have been brought to such distances in cosmological timescales, if it was born in a dark matter halo or globular cluster around the Milky Way.

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Alessandro Ballone, Michela Mapelli, Mario Pasquato. 2018-09-05. Weighing the IMBH candidate CO-0.40-0.22* in the Galactic Centre. https://doi.org/10.1093/mnras%2Fsty2139

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