# Fast and energetic AGN-driven outflows in simulated dwarf galaxies

## TL;DR

This study uses high-resolution simulations to explore how active galactic nuclei (AGN) influence dwarf galaxy evolution, finding that AGN mainly affect outflow properties and may indirectly regulate gas inflows rather than global star formation.

## Contribution

The paper introduces a novel implementation of AGN feedback models in high-resolution dwarf galaxy simulations, analyzing their impact on outflows and star formation.

## Key findings

- AGN outflows increase outflow velocities and temperatures.
- AGN have limited direct impact on global star formation rates.
- AGN may indirectly influence the baryon cycle by hindering gas inflows.

## Abstract

The systematic analysis of optical large-scale surveys has revealed a population of dwarf galaxies hosting AGN, which have been confirmed by X-ray follow-up observations. Recently, the MaNGA survey identified six dwarf galaxies that appear to have an AGN that is preventing on-going star formation. It is therefore timely to study the physical properties of dwarf galaxies, in particular whether the presence of an AGN can affect their evolution. Using the moving mesh code AREPO, we have investigated different models of AGN activity, ranging from simple energy-driven spherical winds to collimated, mass-loaded, bipolar outflows in high resolution simulations of isolated dwarf galaxies hosting an active black hole. Our simulations also include a novel implementation of star formation and mechanical supernova (SN) feedback. We find that AGN outflows have a small but systematic effect on the central star formation rates (SFRs) for all set-ups explored, while substantial effects on the global SFR are only obtained with strong SNe and a sustained high-luminosity AGN with an isotropic wind. This suggests that AGN feedback in dwarf galaxies is unlikely to directly regulate their global SFRs. There is, however, a significant effect on outflow properties, which are notably enhanced by the AGN to much higher outflow temperatures and velocities, in agreement with kinematic signatures from the MaNGA survey. This indicates that AGN may play an indirect role in regulating the baryon cycle in dwarf galaxies by hindering cosmic gas inflows.