GOALS-JWST: Tracing AGN Feedback on the Star-Forming ISM in NGC 7469

TL;DR

This study uses JWST/MIRI spectroscopy to analyze the dust and molecular gas in NGC 7469, revealing how AGN feedback influences star formation and the interstellar medium on ~100 pc scales.

Contribution

First detailed JWST/MIRI observations of a nearby merging galaxy, providing insights into AGN feedback effects on star-forming regions and the ISM.

Findings

Star formation rate of 10-30 solar masses per year in the ring

Detection of 1.2×10^7 solar masses of warm molecular gas

PAH emission weakens near the AGN, indicating dust processing

Abstract

We present James Webb Space Telescope (JWST) Mid-InfraRed Instrument (MIRI) integral-field spectroscopy of the nearby merging, luminous infrared galaxy, NGC 7469. This galaxy hosts a Seyfert type-1.5 nucleus, a highly ionized outflow, and a bright, circumnuclear star-forming ring, making it an ideal target to study AGN feedback in the local Universe. We take advantage of the high spatial/spectral resolution of JWST/MIRI to isolate the star-forming regions surrounding the central active nucleus and study the properties of the dust and warm molecular gas on ~100 pc scales. The starburst ring exhibits prominent Polycyclic Aromatic Hydrocarbon (PAH) emission, with grain sizes and ionization states varying by only ~30%, and a total star formation rate of $\rm 10 - 30 \ M_\odot$/yr derived from fine structure and recombination emission lines. Using pure rotational lines of H2, we detect 1.2$\times$10$^{7} \rm \ M_\odot$ of warm molecular gas at a temperature higher than 200 K in the ring. All PAH bands get significantly weaker towards the central source, where larger and possibly more ionized grains dominate the emission. However, the bulk of the dust and molecular gas in the ring appears unaffected by the ionizing radiation or the outflowing wind from the AGN. These observations highlight the power of JWST to probe the inner regions of dusty, rapidly evolving galaxies for signatures of feedback and inform models that seek to explain the co-evolution of supermassive black holes and their hosts.