JWST Discovery of High-Velocity Mid-Infrared Ionized Outflows in Ultraluminous Infrared Galaxies F11119+3257 and F05189-2524

TL;DR

The study investigates AGN-driven feedback in two local ULIRGs, F11119+3257 and F05189-2524, by leveraging JWST/MIRI MRS to detect ultra-fast, highly ionized outflows. The analysis reveals high-velocity warm ionized outflows with $v_{90} \sim 4000$ km s$^{-1}$ in neon lines, and a extended ($\sim 2$ kpc) biconical component in one source, while a deficit in nuclear H$_2$ emission signals radiative feedback. Energetics indicate the warm ionized gas contributes only $\sim 0.1$–$5\%$ of the momentum flux, supporting a momentum-conserving outflow scenario. Overall, the results corroborate UFO-driven momentum transfer driving galaxy-scale winds and demonstrate JWST’s capability to trace AGN feedback in the MIR at sub-kiloparsec scales.

Abstract

Ultra-fast outflows (UFOs) are thought to be a driving mechanism of large-scale winds driven by active galactic nuclei, which cause significant galactic feedback through quenching star formation and regulating supermassive black hole growth. We present James Webb Space Telescope (JWST) Mid-Infrared Instrument Medium-Resolution Spectrometer observations of two nearby ultraluminous infrared galaxies (ULIRGs), F11119+3257 and F05189-2524, with nuclear X-ray detected UFOs and kiloparsec-scale outflow. These galaxies show remarkably similar mid-infrared continuum and emission line features, notably including a high-velocity $v_{90}$ $\sim$ 4000 km s$^{-1}$ outflow detected in highly ionized neon emission lines, e.g., \nevi. In F05189-2524, we see a slightly slower biconical outflow extending up to $\sim2$ kpc in the same neon emission lines. Both sources show evidence of AGN-driven radiative feedback through a deficit of rotational molecular hydrogen lines in the nuclear region, $<$1 kpc from the central quasar, but no clear evidence of any molecular gas entrained in the quasar-driven outflow. Energetic analysis shows that the warm ionized gas in both of these sources contributes minimally ($\sim0.1-5\%$) to the momentum outflow rate of these sources and leaves the conclusions of previous literature unchanged: the energetics of these sources are broadly consistent with a momentum-conserving outflow.

Figures (3)

• Figure 1: Spectra extracted from 4 sample spaxels, one for each MIRI channel, showing the post JWST pipeline defringing process for the source F05189-2524. Each subplot shows the raw data directly from the JWST pipeline (gray), the data smoothed with a running circular average using a radius of 1.5 spaxels (purple), and the final resulting spectra which has been smoothed and defringed using the JWST pipeline function fit_residual_fringes_1d (red).
• Figure 2: 1D nuclear spectra of F05189-2524 (top) and F11119+3257 (bottom) extracted from the JWST pipeline data cube and corrected for residual fringes. Common MIR spectral features are marked with vertical dashed lines at their rest wavelengths.
• Figure 3: Fit of 1D extracted spectrum (blue) with questfit the continuum fitting package within q3dfit for F05189-2524 (top) and F11119+3257 (bottom). Each spectrum is fit with three black bodies with different temperatures, cool (purple), warm (red), and hot (green), and a PAH template (orange). The total sum fit is the yellow curve.