GATOS: Distinct Feedback Modes in AGN Central Regions Revealed by Spatially Resolved JWST Spectroscopy

Lulu Zhang, Chris Packham, Erin K. S. Hicks, Ismael García-Bernete, Almudena Alonso-Herrero, Ric I. Davies, Martin J. Ward, Daniel E. Delaney, Takuma Izumi, Dimitra Rigopoulou, Cristina Ramos Almeida, Omaira González-Martín, Rogemar A. Riffel, Claudio Ricci, Montserrat Villar-Martín, Francoise Combes, Miguel Pereira-Santaella, Sebastian F. Hoenig, Andrew J. Bunker, Peter G. Boorman, Enrica Bellocchi, Nancy A. Levenson, Santiago García-Burillo, Fergus R. Donnan, Anelise Audibert, Lindsay Fuller, Tanio Díaz-Santos, David J. Rosario

First listed 2026-08-11 | Last updated 2026-08-11

Abstract

Short digest

Using JWST/MIRI MRS spectroscopy at 4–24 pc resolution, GATOS maps PAH bands alongside H₂ and ionized-gas diagnostics across the nuclei of five AGN spanning a broad luminosity range. The study finds that nuclear PAH suppression reflects two distinct feedback channels: AGN irradiation, which heats and ionizes PAHs before preferentially destroying smaller grains, and shock processing from jets or outflows, which preferentially removes ionized PAHs. Their coexistence explains the observed bimodality in PAH band ratios and helps reconcile conflicting PAH-based AGN results, while cautioning that PAH star-formation calibrations in AGN require feedback-aware treatment; the conclusions are based on a limited sample.

Key figures to inspect

• Figure 1. This figure establishes the observational problem by comparing resolved 6.2, 7.7, and 11.3 μm PAH surface brightness with neon-based SFR surface density in the five AGN nuclei. It shows where the usual star-forming PAH–SFR calibration fails on parsec scales, motivating the feedback-based interpretation.
• Figure 4. The central diagnostic figure links PAH 6.2/7.7 and 11.3/7.7 ratios to independent indicators of shock processing and AGN irradiation, while placing the measurements against star-forming spaxels and PAH models. It directly visualizes the two PAH-ratio regimes that underpin the paper’s claim of distinct radiative and kinetic feedback modes.
• Figure 5. This alternate-diagnostic version of the PAH-ratio analysis tests the conclusion using [Fe II]/[Ar II] for shocks and [Ne V]/[Ne III] for AGN irradiation. It matters because it demonstrates that the feedback interpretation is not tied to a single choice of line-ratio proxy.
• Figure 6. The schematic distills the paper’s bottom-line physical picture: irradiation leaves a population weighted toward larger, more ionized PAHs, whereas shocks preferentially destroy ionized PAHs and favor large, neutral survivors. It is the clearest synthesis of why mixed feedback modes can produce bimodal PAH ratios and complicate PAH-based SFR estimates near AGN.