An Analysis of AGN Feedback in the Compact Galaxy Group Stephan's Quintet

TL;DR

This study uses spatially-resolved spectroscopy to analyze the complex kinematics of Stephan's Quintet, revealing AGN-driven outflows, tidal interactions, and their spatial transition, advancing understanding of galaxy interactions and AGN feedback.

Contribution

First detailed biconical outflow model of NGC 7319's narrow-line region, disentangling outflows, rotation, and tidal flows in Stephan's Quintet.

Findings

Outflow velocities up to 550 km/s

Transition from AGN outflows to tidal flows between 2.4-6.3 kpc

Gas shows Seyfert-like ionization out to 6.3 kpc

Abstract

Compact galaxy groups are ideal laboratories for studying the effects of interactions between AGN and multiple nearby galaxies. Recent JWST observations of the nearby compact group Stephan's Quintet highlight tidal flows between the interacting galaxies as well as outflows from the active galaxy NGC 7319. To study the kinematics on a large scale throughout the group, we obtained spatially-resolved long-slit spectra of Stephan's Quintet at multiple slit positions with Apache Point Observatory's Kitt Peak Ohio State Multi-Object Spectrograph. We fit multiple Gaussians to the H$\alpha$ $\lambda$6563 \r{A} and [N II] $\lambda\lambda$6548, 6583 \r{A} emission lines to isolate the different kinematic components. We used the kinematics to develop the first biconical outflow model of the narrow-line region of NGC 7319. Using a combination of galactic rotation models, biconical outflow models, and kinematic maps of the ionized gas, we disentangled the outflows, rotation, and tidal flows in the group. We found outflow radial velocities up to 550 km s$^{-1}$ peaking at 2.6 kpc from the central supermassive black hole, and a transition from AGN-powered outflows to gravitationally-powered tidal flows at a projected distance between 2.4 -- 6.3 kpc. We performed a line ratio analysis and determined the gas shows Seyfert-like ionization out to 6.3 kpc (projected), which supports our finding that gas outside this radius is predominantly powered by tidal flows. Our separation of kinematic components in Stephan's Quintet will enable future studies of the physical conditions and dynamical forces in the ionized gas to better quantify the feeding and feedback processes of AGN in compact groups.