Quenching star formation with low-luminosity AGN winds

Abstract

ABSTRACT We present a simple model for low-luminosity active galactic nucleus (LLAGN) feedback through winds produced by a hot accretion flow. The wind carries considerable energy and deposits it on the host galaxy at kiloparsec scales and beyond, heating the galactic gas and thereby quenching star formation. Our model predicts that the typical LLAGN can quench more than 10 per cent of star formation in its host galaxy. We find that long-lived LLAGN winds from supermassive black holes (SMBHs) with masses ≥108 M⊙ and mass accretion rates $\dot{M} \gt 10^{-3} \dot{M}_{\rm Edd}\ (0.002\,{\rm M}_{\odot }\,\mathrm{ yr}^{-1})$ can prevent gas collapse and significantly quench galactic star formation compared to a scenario without AGNs, if the wind persists over 1 Myr. For sustained wind production over time-scales of 10 Myr or longer, SMBHs with 108 M⊙ or larger masses have important feedback effects with $\dot{M} \gt 10^{-4} \dot{M}_{\rm Edd}\ (0.0002\,{\rm M}_{\odot }\, \mathrm{ yr}^{-1})$.