Decoupling the AGN outflow and star-forming disk kinematics in the nuclear region of NGC 7582 with JWST NIRSpec and MIRI/MRS

Oscar Veenema, Niranjan Thatte, Dimitra Rigopoulou, Ismael García-Bernete, Almudena Alonso-Herrero, Miguel Pereira-Santaella, Anelise Audibert, Enrica Bellocchi, Andrew J. Bunker, Steph Campbell, Francoise Combes, Ric I. Davies, Fergus R. Donnan, Santiago García-Burillo, Omaira Gonzalez Martin, Laura Hermosa Muñoz, Erin K. S. Hicks, Sebastian F. Hoenig, Alvaro Labiano, Nancy A. Levenson, Chris Packham, Cristina Ramos Almeida, Claudio Ricci, Rogemar A. Riffel, David Rosario, Taro Shimizu, Lulu Zhang

First listed 2026-04-27 | Last updated 2026-04-27

Abstract

We present a detailed study of the inner regions of NGC~7582, a nearby Seyfert~2 galaxy, from the Galaxy Activity, Torus and Outflow Survey (GATOS). The galaxy hosts a circumnuclear star-forming disk and an AGN-driven biconical ionised outflow. Using JWST NIRSpec and MIRI/MRS integral-field spectroscopy, we analyse ionic emission lines spanning a wide range of ionisation potentials (IPs, $\sim 8$--$126$ eV). Gaussian line-profile fitting reveals kinematic stratification: low-IP species ($\lesssim 20$ eV; e.g., [Fe II], [Ar II], [Ne II]) trace ordered disk rotation with PA $\sim -12 \pm 3^\circ$, while high-IP species ($\gtrsim 35$ eV; e.g., [O IV], [Mg IV], [Ne V]) follow the outflow with PA $\sim 54 \pm 10^\circ$. Outflowing gas exhibits systematically higher velocity dispersions ($119 \pm 13$ km/s) than the disk ($78 \pm 11$ km/s), consistent with turbulent or bulk motions. Intermediate-IP lines, [S III], [Ar III], and [Ne III], show contributions from both components, with the outflow characterised by higher dispersion, lower amplitude, and higher velocities in double-Gaussian fits. For these lines, a thin inclined disk plus one-dimensional outflow model enables robust separation and quantification of the disk and outflow velocity fields. The outflow is consistent with a hollow bicone capable of accelerating gas beyond the local escape velocity, implying most material is unlikely to be re-accreted. The ionisation cone opening angle shows no dependence on IP, indicating the AGN torus polar regions are largely unobscured. Our study provides new insights into AGN-driven outflows and circumnuclear disk dynamics, offering a framework to disentangle overlapping ISM kinematics in nearby active galaxies.

Short digest

JWST/NIRSpec and MIRI/MRS IFS map ionic lines spanning ~8–126 eV in NGC 7582’s nucleus, cleanly separating the rotating circumnuclear disk from an AGN-driven outflow. Single/double-Gaussian fitting shows low-IP ([Fe II], [Ar II], [Ne II]) lines track disk rotation at PA ≈ −12 ± 3°, while high-IP ([O IV], [Mg IV], [Ne V]) align with a bicone outflow at PA ≈ 54 ± 10°, with higher dispersions in the outflow (σ ≈ 119 ± 13 km/s) than in the disk (σ ≈ 78 ± 11 km/s). Intermediate-IP lines ([S III], [Ar III], [Ne III]) carry both components, and a thin inclined disk plus 1D outflow model robustly decouples and quantifies their velocity fields. The outflow is a hollow bicone capable of accelerating gas beyond the local escape speed, with an opening angle independent of IP, implying largely unobscured polar regions of the torus.

Key figures to inspect

• Figure 1: Use the [Ar II], [Ar III], and [Ne V] flux maps to outline the circumnuclear disk/ring, pinpoint SF1/SF2 star-forming clumps, and trace the limb-brightened ionisation cones; note the stronger, blueshifted western cone versus the receding eastern side, anchored to the AGN continuum peak.
• Figure 2: Inspect velocity fields ordered by IP to verify the PA flip between disk rotation and outflow; low-IP maps show coherent rotation, while high-IP maps align with the bicone, quantifying the ≈−12° vs ≈54° axes and the stratified kinematics.
• Figure 3: Compare continuum-subtracted flux distributions across IP to see low-IP emission concentrated in the star-forming ring and high-IP emission extending along the cones; intermediate-IP lines reveal spatial mixing of disk and outflow.
• Figure 4: Examine velocity dispersion maps to confirm σ contrasts—low in the ring, elevated in the cones—supporting the double-Gaussian decomposition (outflow = higher σ, lower amplitude, higher centroid velocities).