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arXiv · 2301.07155

An increase in black hole activity in galaxies with kinematically misaligned gas

Sandra I. Raimundo·Matthew Malkan·Marianne Vestergaard
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Abstract

External accretion events such as a galaxy merger or the accretion of gas from the immediate environment of a galaxy, can create a large misalignment between the gas and the stellar kinematics. Numerical simulations have suggested that misaligned structures may promote the inflow of gas to the nucleus of the galaxy and the accretion of gas by the central supermassive black hole. We show for the first time that galaxies with a strong misalignment between the ionised gas and stellar kinematic angles have a higher observed fraction of active black holes than galaxies with aligned rotation of gas and stars. The increase in black hole activity suggests that the process of formation and/or presence of misaligned structures is connected with the fuelling of active supermassive black holes.

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Sandra I. Raimundo, Matthew Malkan, Marianne Vestergaard. 2023-01-17. An increase in black hole activity in galaxies with kinematically misaligned gas. https://doi.org/10.1038/s41550-022-01880-z

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