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Title: The Impact of AGN Wind Feedback in Simulations of Isolated Galaxies with a Multiphase ISM
Abstract Accreting black holes can drive fast and energetic nuclear winds that may be an important feedback mechanism associated with active galactic nuclei (AGN). In this paper, we implement a scheme for capturing feedback from these fast nuclear winds and examine their impact in simulations of isolated disk galaxies. Stellar feedback is modeled using the FIRE physics and produces a realistic multiphase interstellar medium (ISM). We find that AGN winds drive the formation of a low-density, high-temperature central gas cavity that is broadly consistent with analytic model expectations. The effects of AGN feedback on the host galaxy are a strong function of the wind kinetic power and momentum. Low and moderate luminosity AGN do not have a significant effect on their host galaxy: the AGN winds inefficiently couple to the ambient ISM and instead a significant fraction of their energy vents in the polar direction. For such massive black holes, accretion near the Eddington limit can have a dramatic impact on the host galaxy ISM: if AGN wind feedback acts for ≳ 20 − 30 Myr, the inner ∼1 − 10 kpc of the ISM is disrupted and the global galaxy star formation rate is significantly reduced. We quantify the properties of more » the resulting galaxy-scale outflows and find that the radial momentum in the outflow is boosted by a factor ∼2 − 3 relative to that initially supplied in the AGN wind for strong feedback scenarios, decreasing below unity for less energetic winds. In contrast to observations, however, the outflows are primarily hot, with very little atomic or molecular gas. We conjecture that merging galaxies and high-redshift galaxies, which have more turbulent and thicker disks and very different nuclear gas geometries, may be even more disrupted by AGN winds than found in our simulations. « less
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Award ID(s):
1715216 1715847 1909933 1909831 1715101
Publication Date:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Sponsoring Org:
National Science Foundation
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