The Physics, Observational Signatures, and Consequences of AGN-Driven Galactic Winds

Project: Research project

Description

Objectives, Expected Significance, and Overview of Proposed Work
How feedback from active galactic nuclei (AGN) a↵ects galaxy evolution is arguably the most pressing open question in galaxy evolution. AGN feedback is likely needed to explain the red colors of the most massive galaxies, may play a significant role in suppressing the stellar masses of galaxies above ⇠ L⇤, and may also establish the observed black hole (BH)-galaxy scaling relations (for a review, see Fabian 2012). In recent years, cosmological simulations that implement radiative and supernova (SN) feedback from massive stars have made important strides in demonstrating that stellar feedback is key to explaining the main properties of galaxies below ⇠ L⇤ (up to about the mass of the Milky Way) across cosmic time. For example, simulations from the FIRE
project,1 simultaneously reproduce observed galaxy stellar masses (Hopkins et al. 2014), massmetallicity relations (Ma, Hopkins, Faucher-Gigu`ere et al. 2016), and the HI content of galaxy halos (Faucher-Gigu`ere et al. 2015, 2016; Hafen, Faucher-Gigu`ere et al., submitted) at all redshifts where observations are available. These successes rely critically on star formation-driven galactic winds with roughly the correct bulk properties (Muratov, Kereˇs, Faucher-Gigu`ere et al. 2015). Other groups have also obtained broadly consistent results (e.g., Guedes et al. 2011; Stinson et al. 2013; Vogelsberger et al. 2014; Schaye et al. 2015; Agertz and Kravtsov 2015; Dav´e et al. 2016). How the energy released as supermassive BHs grow couples to the surrounding galaxy, and whether
or how it shapes galaxies is however much less clear. This is because unlike for the vast literature on, e.g. the physics of SN feedback, we do not yet have a good and comprehensive understanding of the basic physics of AGN feedback. Until recently, direct observations of AGN feedback in action were also lacking (except for powerful radio jets, whose role is relatively well established in galaxy clusters, but which do not directly the majority of lower-mass galaxies).
StatusActive
Effective start/end date7/1/186/30/21

Funding

  • NASA Goddard Space Flight Center (80NSSC18K1096 P00001)

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galactic winds
active galactic nuclei
signatures
galaxies
physics
stellar mass
supernovae
pressing
massive stars
star formation
halos