AGN Feedback Models and AGN Demographics. I. Radio-mode AGN in EAGLE, SIMBA, and TNG100 Are Inconsistent with Observations
Year: 2026
Type: article
Abstract: We compare predictions of how active galactic nuclei (AGNs) populate host galaxies at low redshifts to observations, finding large discrepancies between cosmological simulation predictions and observed patterns. Modern cosmological simulations include AGN feedback models tuned to reproduce the observed galaxy stellar mass function. However, due to a lack of real understanding of the physics of AGN feedback, these models vary significantly across simulations. To distinguish between the models and potentially test the underlying physics, we carry out independent tests of these models. In an earlier study, we found that F AGN —the observed completeness-corrected fraction of galaxies hosting radio AGNs with an Eddington ratio λ > 10 −3 —to be a strong function of host-galaxy stellar mass ( M ⋆ ) but nearly independent of host specific star formation rates (sSFRs) at fixed M ⋆ . In this study, we test the radio mode AGN feedback models of the EAGLE, SIMBA, and TNG100 simulations by comparing their predictions of F AGN M ⋆ to our observational constraint. We find that none of these simulations even qualitatively reproduce the observed dependencies of F AGN on M ⋆ and sSFR. Finally, we find that although the given TNG100 model could be modified in order to better reproduce the observed F AGN trend, this modification would likely also change its prediction for the local stellar mass function and star formation rates—key observations used for calibrating the simulation in the first place. Our findings highlight a pressing need to revisit the AGN feedback prescriptions in EAGLE, SIMBA, TNG100, and other similar models.
Source: The Astrophysical Journal
Institutions: New York University, Flatiron Institute
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Science Foundation, Smithsonian Institution, U.S. Department of Energy, National Aeronautics and Space Administration, Alfred P. Sloan Foundation, Yale University, Carnegie Institution of Washington, Vanderbilt University, Ohio State University, Helsingin Yliopisto, University of Washington, Johns Hopkins University, Carnegie Mellon University, University of Notre Dame, University of Portsmouth, New Mexico State University, York University, University of Cambridge, University of Oxford, European Commission, Durham University, University of Hertfordshire, Belgian Federal Science Policy Office, Nederlandse Organisatie voor Wetenschappelijk Onderzoek, Ministério da Ciência, Tecnologia e Inovação, Universidad Nacional Autónoma de México, Max-Planck-Institut für Astrophysik, Max-Planck-Institut für Astronomie, Gauss Centre for Supercomputing, Instituto de Astrofísica de Canarias, Office of Science, University of Colorado Boulder, Science and Technology Facilities Council, Leibniz-Gemeinschaft, Lawrence Berkeley National Laboratory
Awards: G1381339075, Durham DiRAC-2 petascale facility, DiRAC-2.5 - the pathway to DiRAC Phase 3, G2288345500, G2309215924, G2368581224, G2566822479, G2861369480, G296705498, G3090041109, G3363198467, G3467815775, G3859923413, G4188279732, G4251892262, G4831232377, G4848836895, G5385953647, G6583118092, DiRAC: Memory Intensive 2.5y, G8092745986, The Virgo consortium for cosmological supercomputer simulations, DiRAC: Memory Intensive 2.5x
OpenAlex ID: W7124429531