# Star Formation History in Barred Spiral Galaxies. AGN Feedback

## TL;DR

This study uses hydrodynamical simulations to explore how AGN feedback influences star formation in barred and unbarred spiral galaxies, revealing a complex interplay of positive and negative effects that largely cancel out.

## Contribution

It provides a detailed numerical analysis of AGN feedback effects on star formation distribution in barred and unbarred galaxies, highlighting the balance of positive and negative feedback mechanisms.

## Key findings

- AGN feedback suppresses central star formation.
- Star formation shifts to larger radii due to feedback.
- Negative feedback dominates in unbarred galaxies.

## Abstract

We present a numerical study of the impact of AGN accretion and feedback on the star formation history of barred disc galaxies. Our goal is to determine whether the effect of feedback is positive (enhanced star formation) or negative (quenched star formation), and to what extent. We performed a series of 12 hydrodynamical simulations of disc galaxies, 10 barred and 2 unbarred, with various initial gas fractions and AGN feedback prescriptions. In barred galaxies, gas is driven toward the centre of the galaxy and causes a starburst, followed by a slow decay, while in unbarred galaxies the SFR increases slowly and steadily. AGN feedback suppresses star formation near the central black hole. Gas is pushed away from the black hole, and collides head-on with inflowing gas, forming a dense ring at a finite radius where star formation is enhanced. We conclude that both negative and positive feedback are present, and these effects mostly cancel out. There is no net quenching or enhancement in star formation, but rather a displacement of the star formation sites to larger radii. In unbarred galaxies, where the density of the central gas is lower, quenching of star formation near the black hole is more efficient, and enhancement of star formation at larger radii is less efficient. As a result, negative feedback dominates. Lowering the gas fraction reduces the star formation rate at all radii, whether or not there is a bar or an AGN.