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Updated: Jul 11, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Supermassive black hole feeding and feedback observed on subparsec scales
Takuma Izumi1,2,3, Keiichi Wada4,5,6, Masatoshi Imanishi1,3
1National Astronomical Observatory of Japan, Tokyo 181-8588, Japan.
Abstract:
Active galaxies contain a supermassive black hole at their center that grows by accreting matter from the surrounding galaxy. The accretion process in about the central 10 parsecs has not been directly resolved in previous observations because of the small apparent angular sizes involved. We observed the active nucleus of the Circinus Galaxy using submillimeter interferometry. A dense inflow of molecular gas was evident on subparsec scales. We calculated that less than 3% of this inflow is accreted by the black hole, with the rest being ejected by multiphase outflows, providing feedback to the host galaxy. Our observations also reveal a dense gas disk surrounding the inflow that is gravitationally unstable, which drives the accretion into about the central 1 parsec.
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