Star Formation and AGN Feedback in the Local Universe: Combining LOFAR and MaNGA

TL;DR

This study investigates the impact of radio-detected AGN on star formation in local galaxies by combining deep radio and optical integral field spectroscopy data, finding that current AGN activity does not suppress star formation but may help maintain it.

Contribution

It combines LOFAR radio survey data with MaNGA optical spectroscopy to analyze star formation in AGN-hosting galaxies, providing new insights into AGN feedback effects.

Findings

RDAGN and control galaxies have similar broad SFR distributions.

Most galaxies lie below the star-forming main-sequence.

AGN activity does not appear to suppress star formation.

Abstract

The effect of Active Galactic Nuclei (AGN) on their host galaxies -- in particular their levels of star formation -- remains one of the key outstanding questions of galaxy evolution. Successful cosmological models of galaxy evolution require a fraction of energy released by an AGN to be redistributed into the interstellar medium to reproduce the observed stellar mass and luminosity function and to prevent the formation of over-massive galaxies. Observations have confirmed that the radio-AGN population is energetically capable of heating and redistributing gas at all phases, however, direct evidence of AGN enhancing or quenching star formation remains rare. With modern, deep radio surveys and large integral field spectroscopy (IFS) surveys, we can detect fainter synchrotron emission from AGN jets and accurately probe the star-forming properties of galaxies, respectively. In this paper, we combine data from the LOw Frequency ARray Two-meter Sky Survey with data from one of the largest optical IFS surveys, Mapping Nearby Galaxies at Apache Point Observatory to probe the star-forming properties of 307 local (z $<$ 0.15) galaxies that host radio-detected AGN (RDAGN). We compare our results to a robust control sample of non-active galaxies that each match the stellar mass, redshift, visual morphology, and inclination of a RDAGN host. We find that RDAGN and control galaxies have broad SFR distributions, typically lie below the star-forming main-sequence, and have negative stellar light-weighted age gradients. These results indicate that AGN selected based on their current activity are not responsible for suppressing their host galaxies' star formation. Rather, our results support the maintenance mode role that radio AGN are expected to have in the local Universe.