Do AGN really suppress star formation?
Journal article, 2019

Active galactic nuclei (AGN) are believed to regulate star formation inside their host galaxies through "AGN feedback". We summarise our on-going study of luminous AGN (z ∼0.2-3; LAGN,bol 1043 erg s-1), which is designed to search for observational signatures of feedback by combining observed star-formation rate (SFR) measurements from statistical samples with cosmological model predictions. Using the EAGLE hydrodynamical cosmological simulations, in combination with our Herschel + ALMA surveys, we show that - even in the presence of AGN feedback - we do not necessarily expect to see any relationships between average galaxy-wide SFRs and instantaneous AGN luminosities. We caution that the correlation with stellar mass for both SFR and AGN luminosity can contribute to apparent observed positive trends between these two quantities. On the other hand, the EAGLE simulations, which reproduce our observations, predict that a signature of AGN feedback can be seen in the wide specific SFR distributions of all massive galaxies (not just AGN hosts). Overall, whilst we can not rule out that AGN have an immediate small-scale impact on in-situ star-formation, all of our results are consistent with a feedback model where galaxy-wide in-situ star formation is not rapidly suppressed by AGN, but where the feedback likely acts over a longer timescale than a single AGN episode.

galaxies: evolution

galaxies: active

Author

C. M. Harrison

Newcastle University

David M. Alexander

Durham University

Dalton J. Rosario

Durham University

Jan Scholtz

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Durham University

Flora Stanley

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

Proceedings of the International Astronomical Union

1743-9213 (ISSN) 1743-9221 (eISSN)

Vol. 15 199-203

Subject Categories

Meteorology and Atmospheric Sciences

Astronomy, Astrophysics and Cosmology

Bioinformatics (Computational Biology)

DOI

10.1017/S1743921320002902

More information

Latest update

11/14/2023