AGN and Star Formation Feedback in Galaxy Outflows

TL;DR

This study uses 3D MHD simulations to explore how AGN and supernova feedback jointly drive galaxy outflows, revealing the dynamics, gas exhaustion, and velocity characteristics of these complex phenomena.

Contribution

It presents the first detailed 3D radiative-cooling MHD simulations considering both AGN and supernova feedback in galaxy outflows.

Findings

AGN winds create fountain structures causing gas fallback.

AGN winds rapidly deplete nuclear gas, quenching star formation.

Supernova-driven winds dominate the mass-loading of outflows.

Abstract

Large-scale, broad outflows are common in active galaxies. In systems where star formation coexists with an AGN, it is unclear yet the role that both play on driving the outflows. In this work we present three-dimensional radiative-cooling MHD simulations of the formation of these outflows, considering the feedback from both the AGN and supernovae-driven winds. We find that a large-opening-angle AGN wind develops fountain structures that make the expanding gas to fall back. Furthermore, it exhausts the gas near the nuclear region, extinguishing star formation and accretion within a few 100.000 yr, which establishes the duty cycle of these outflows. The AGN wind accounts for the highest speed features in the outflow with velocities around 10.000 km s$^{-1}$ (as observed in UFOs), but these are not as cold and dense as required by observations of molecular outflows. The SNe-driven wind is the main responsible for the observed mass-loading of the outflows.