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David S. N. Rupke

Publications and source records attributed to David S. N. Rupke.

At least 19 recordsLinked to original sources

The interplay between active galactic nucleus photoionization, radio jet, and star formation in the z $\sim$ 3.5 radio galaxy 4C +03.24

High-redshift radio galaxies (HzRGs) are among the most powerful radio sources, and are associated with the most massive galaxies and dense environments at redshifts z $\gtrsim$ 1. They are ideal laboratories for studying how active galactic nucleus (AGN) events can shape the evolution of galaxies, as intense radiation, jets, and star formation can be observed simultaneously in these galaxies. We present JWST/NIRSpec integral field spectroscopy ($\sim$ 1.6 kpc spatial resolution) of the 4C +03.24 system, a powerful HzRG at z $\sim$ 3.5 with a bolometric luminosity of $\sim 10^{47.6}$ erg s$^{-1}$. We identified kinematically disturbed regions in the warm ($\sim 10^4$ K) ionized gas by decomposing the emission-line spectra into multiple Gaussian components, which is crucial to avoid overestimating the outflow properties. The outflow power peaks at $\sim$ 2 kpc away from the nucleus, with a corresponding low kinetic coupling efficiency of $\sim 8_{-5}^{+7} \times 10^{-3}$ %. A combined analysis of the rest-frame optical and ultraviolet (from VLT/MUSE and HST imaging) continua revealed an extended emission (spanning $\sim$ 14 kpc), which we interpret as partially tracing star-forming regions. With a clearly delineated bipolar morphology, we show that the AGN photoionization dominates the ionization of the interstellar medium along the radio jet axis. The [C II]$λ$158$μ$m emission gap in this region might be direct evidence of negative AGN feedback. We also discuss a possible scenario where 4C +03.24 could be situated in an overdense environment experiencing multiple galaxy interactions and the possibility of jet-induced star-formation.

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First Results from the JWST Early Release Science Program Q3D: AGN Photoionization and Shock Ionization in a Red Quasar at $z = 0.4$

Red quasars, often associated with powerful [O III] outflows on both galactic and circumgalactic scales, may play a pivotal role in galaxy evolution and black hole feedback. In this work, we explore the [Fe II] emission in one such quasar at redshift $z = 0.4352$, F2M J110648.32+480712.3, using the integral field unit (IFU) mode of the Near Infrared Spectrograph (NIRSpec) aboard the James Webb Space Telescope (JWST). Our observations reveal clumpy [Fe II] gas located to the south of the quasar. By comparing the kinematics of [Fe II] and [O III], we find that the clumpy [Fe II] gas in the southeast and southwest aligns with the outflow, exhibiting similar median velocities up to $v_{50} \sim 1200$ km/s and high velocity widths $W_{80} > 1000$ km/s. In contrast, the [Fe II] gas to the south shows kinematics inconsistent with the outflow, with $W_{80} \sim 500$ km/s, significantly smaller than the [O III] at the same location, suggesting that the [Fe II] may be confined within the host galaxy. Using standard emission-line diagnostic ratios, we map the ionization sources of the gas. According to the MAPPINGS III shock models for [Fe II]/Pa$β$, the regions to the southwest and southeast of the quasar are primarily photoionized. Conversely, the [Fe II] emission to the south is likely excited by shocks generated by the back-pressure of the outflow on the galaxy disk, a direct signature of the impact of the quasar on its host.

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A Shocked Wind Interpretation of an Odd Radio Circle

Odd Radio Circles (ORCs) are a new class of extragalactic object, with large rings of faint radio continuum emission typically spanning 100s of kpc; their origins are unknown. Previous optical spectroscopy of the central galaxy in ORC4, a classic isolated ORC, revealed spatially-extended ionized gas with strong [OII] emission and line ratios consistent with LINER emission. We present new Keck/KCWI+KCRM integral field spectroscopy covering multiple strong optical emission lines to measure the extent, morphology, and spatially-resolved kinematics and line ratios of the ionized and neutral gas in the ORC4 central galaxy. We find that [OII] is the strongest optical emission line in this massive, old galaxy, and the [OII] emission is detected to larger radial extent than the other optical lines. The gas kinematics show strong spatial asymmetries, high velocity gradients (>100 km/s), and high velocity dispersion (~200 km/s). The emission line ratios are most consistent with shock models with shock velocities of ~200-300 km/s and are not fit well by stellar or AGN photoionization models. These findings are consistent with a model in which the gas in the ORC4 central galaxy is the result of shock ionization in and around the central galaxy, likely due to mixing and cooling of gas associated with the event that created the large-scale radio ring of emission that identified this source as an ORC.

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Shedding the envelope: JWST reveals a kiloparsec-scale [OIII]-weak Balmer shell around a z=7.64 quasar

Luminous quasars at the redshift frontier z>7 serve as stringent probes of super-massive black hole formation and they are thought to undergo much of their growth obscured by dense gas and dust in their host galaxies. Fully characterizing the symbiotic evolution of SMBHs and hosts requires rest-frame optical observations that span spatial scales from the broad-line region to the ISM and CGM. JWST now provides the necessary spatially resolved spectroscopy to do so. But the physical conditions that regulate the interplay between SMBHs and their hosts at the highest redshifts, especially the nature of early feedback phases, remain unclear. We present JWST/NIRSpec IFU observations of J0313$-$1806 at z=7.64, the most distant luminous quasar known. From the restframe optical spectrum of the unresolved quasar, we derive a black hole mass of $M_\mathrm{BH}=(1.63 \pm 0.10)\times10^9 M_\odot$ based on H$β$ and an Eddington rate of $λ=L/L_\mathrm{Edd}=0.80\pm 0.05$, consistent with previous MgII-based estimates. J0313-1806 exhibits no detectable [O III] emission on nuclear scales. Most remarkably, we detect an ionized gas shell extending out to $\sim 1.8$ kpc traced by H$β$ emission that also lacks any significant [O III], with a $3σ$ upper limit on the [O III]$ λ$5007 to H$β$ flux ratio of $\log_{10} \left( F(\mathrm{[OIII]})/F(\mathrm{H}β)\right)=-1.15$. Through photoionization modelling, we demonstrate that the extended emission is consistent with a thin, clumpy outflowing shell where [OIII] is collisionally de-excited by dense gas. We interpret this structure as a fossil remnant of a recent blowout phase, providing evidence for episodic feedback cycles in one of the earliest quasars. These findings suggest that dense ISM phases may play a crucial role in shaping the spectral properties of quasars accross cosmic time.

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JWST Discovery of Warm Dust in the Circumgalactic Medium of the Makani Galaxy

We report the detection of near- and mid-infrared emission from polycyclic aromatic hydrocarbons (PAHs) out to ~ 35 kpc in the Makani Galaxy, a compact massive galaxy with a record-breaking 100-kpc scale starburst-driven wind at redshift z = 0.459. The NIRCam and MIRI observations with JWST take advantage of a coincidental match between the PAH spectral features at 3.3, 7.7, and (11.3 + 12.2) microns in Makani and the bandpasses of the MIRI and NIRCam filters. The warm dust is not only detected in the cool-gas tracers of the galactic wind associated with the more recent (7 Myr) starburst episode, but also in the outer warm-ionized gas wind produced by the older (0.4 Gyr) episode. The presence of PAHs in the outer wind indicates that the PAHs have survived the long (R/v ~ 10^8 yrs) journey to the halo despite the harsh environment of the galactic wind. The measured F1800W/F1130W flux ratios in the unresolved nucleus, inner halo (R = 10 - 20 kpc), and outer halo (R = 20 - 35 kpc), tracers of the PAH (11.3 + 12.2)/7.7 ratios, indicate decreasing starlight intensity incident on the PAHs, decreasing PAH sizes, and increasing PAH ionization fractions with increasing distance from the nucleus. These data provide the strongest evidence to date that the ejected dust of galactic winds survives the long journey to the CGM, but is eroded along the way.

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Mapping Galactic Winds and Small-scale Structure in the Circumgalactic Medium with Habitable Worlds Observatory

We present a science case for the Habitable Worlds Observatory (HWO) to map the circumgalactic medium (CGM) in emission by targeting ultraviolet emission lines, which trace the 10^4 - 10^6 K gas engaged in the feedback and accretion mechanisms driving galaxy evolution. While the CGM-galaxy connection is clearly evident through absorption line experiments and limited work done in optical and radio emission from the ground, the nature of this connection is poorly understood with regard to how these cosmic ecosystems exchange matter and energy. We outline a two-pronged experiment with Habitable Worlds Observatory (HWO) utilizing both multi-object spectroscopy to map kpc-scale CGM structures such as galactic superwinds and integral field spectroscopy to unveil the sub-kpc-scale processes such as thermal instabilities, which are theorized to govern the cool gas reservoirs long detected in pencil-beam absorption surveys. This article is an adaptation of a science case document developed by HWO's CGM/IGM Working Group.

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JWST IFU observations uncover host galaxy continua in extremely red and obscured quasars

Uncovering bright quasars' host galaxies at cosmic noon is challenging because of the high contrast between the quasar and its host and redshifted light, making them primarily visible in the infrared. We present JWST NIRSpec integral field unit (IFU) observations of six extremely red quasars (ERQs) at $z=2.4-2.9$ and two dust-obscured quasars at lower redshifts. Using image decomposition across the spectral range, we successfully separate quasar and host galaxy continuum emission, model host morphologies, and extract spectra. The ERQs and obscured quasars have compact host galaxies with half-light radii of 1.4$-$2.9 kpc and stellar masses of 10$^{10.6-10.9}$ $M_{\odot}$. Their stellar masses are consistent with the average stellar mass of quasar hosts as expected from abundance matching and clustering analysis. Most of the quasars in our sample exhibit significant spatial offsets (0.4$-$1.3 kpc) between the quasar and host galaxy, potentially caused by post-merger dynamics or non-uniform dust obscuration. The ERQs reside 0.5$-$2 dex above the local black hole-stellar mass relation, similar to other heavily obscured populations such as HotDOGs, optically selected quasars at cosmic noon, and high-redshift SMBH candidates identified with JWST. However, this "over-massive" feature might be attributed to selection bias. Compared to HST-based studies, our JWST measurements reveal more compact host galaxies, smaller Sersic indices, and lower stellar masses, likely because of improved resolution, more accurate modeling, and minimal line contamination. These findings highlight the unique capabilities of JWST IFU in revealing quasar host galaxy properties and potential evolutionary stages of obscured quasars at cosmic noon.

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JWST + ALMA ubiquitously discover companion systems within $\lesssim18\,$kpc around four $z$$\approx$3.5 luminous radio-loud AGN

Mergers play important roles in galaxy evolution at and beyond Cosmic Noon ($z\sim3$). They are found to be a trigger of active galactic nuclei (AGN) activity and a process for growing stellar mass and black hole mass. High-$z$ radio galaxies (HzRGs=type-2 radio-loud AGN) are among the most massive galaxies known, and reside in dense environments on scales of tens of kiloparsecs to Megaparsecs. We present the first search for kpc-scale companions in a sample of four $z\sim3.5$ HzRGs, with many supporting datasets, using matched 0.2" resolution ALMA and JWST/NIRSpec integral field unit data. We discover a total of $\sim12$ companion systems within $\lesssim18\,$kpc across all four HzRG fields using two independent detection methods: peculiar [OIII]$4959,5007$ kinematics offset from the main (systemic) ionized gas component and [CII]$158\rm μm$ emitters. We examine the velocity fields of these companions and find evidence of disk rotation along with more complex motions. We estimate the dynamical masses of these nearby systems to be $M_{\rm dyn}\sim10^{9-11}\,M_{\odot}$, which may indicate a minor merger scenario. Our results indicate that these companions may be the trigger of the powerful radio-loud AGN. We discuss the roles of the discovered companion systems in galaxy evolution for these powerful jetted AGN and indicate that they may impede jet launch and deflect the jet.

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VODKA-JWST: Synchronized growth of two SMBHs in a massive gas disk? A 3.8 kpc separation dual quasar at cosmic noon with NIRSpec IFU

The search for dual supermassive black holes (SMBHs) is of immense interest in modern astrophysics. Galaxy mergers may fuel and produce SMBH pairs. Actively accreting SMBH pairs are observed as a dual quasar, which are vital probes of SMBH growth. Dual quasars at cosmic noon are not well characterized. Gaia observations have enabled a novel technique to identify dual quasars at kpc scales, based on the small jitters of the light centroid as the two quasars vary stochastically. We present the first detailed study of a z=2.17, 0.46'', 3.8 kpc separation dual quasar, J0749+2255, using JWST/NIRSpec integral field unit spectroscopy. Identified by Gaia, J0749+2255 is one of the most distant, small separation dual quasars known. We detect the faint ionized gas of the host galaxy, traced by the narrow Ha emission. Line ratios indicate ionization from the two quasars and from intense star formation. Spectral analysis of the two quasars suggests that they have similar black hole properties, hinting at the possible synchronized accretion activity or lensed quasar images. Surprisingly, the ionized gas kinematics suggest a rotating disk rather than a disturbed system expected in a major gas-rich galaxy merger. Numerical simulations show that this is a plausible outcome of a major gas-rich galaxy merger several tens of Myr before coalescence. Whether J0749+2255 reflects an interesting phase of dual quasar evolution or is a lensed quasar remains unclear. Thus, this study underscores the challenges in definitively distinguishing between a dual and lensed quasars, with observations supporting either scenario.

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Resolving turbulence drivers in two luminous obscured quasars with JWST/NIRSpec IFU

In this Letter, we investigate the turbulence and energy injection in the extended nebulae surrounding two luminous obscured quasars, WISEA J100211.29$+$013706.7 ($z=1.5933$) and SDSS J165202.64$+$172852.3 ($z=2.9489$). Utilizing high-resolution data from the NIRSpec IFU onboard the James Webb Space Telescope, we analyze the velocity fields of line-emitting gas in and around these quasars and construct the second-order velocity structure functions (VSFs) to quantify turbulent motions across different spatial scales. Our findings reveal a notable flattening in the VSFs from $\approx\!3$ kpc up to a scale of 10--20 kpc, suggesting that energy injection predominantly occurs at a scale $\lesssim$10 kpc, likely powered by quasar outflows and jet-driven bubbles. The extended spatial range of flat VSFs may also indicate the presence of multiple energy injection sources at these scales. For J1652, the turbulent energy in the host interstellar medium (ISM) is significantly higher than in tidally stripped gas, consistent with the expectation of active galactic nucleus (AGN) activities stirring up the host ISM. Compared to the VSFs observed on spatial scales of 10--50 kpc around lower-redshift UV-bright quasars, these obscured quasars exhibit higher turbulent energies in their immediate surroundings, implying different turbulence drivers between the ISM and halo-scale gas. Future studies with an expanded sample are essential to elucidate further the extent and the pivotal role of AGNs in shaping the gas kinematics of host galaxies and beyond.

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First results from the JWST Early Release Science Program Q3D: The Fast Outflow in a Red Quasar at z=0.44

Quasar feedback may play a key role in the evolution of massive galaxies. The dust-reddened quasar, F2M110648.35$+$480712 at $z = 0.4352$ is one of the few cases at its redshift that exhibits powerful quasar feedback through bipolar outflows. Our new observation with the integral field unit mode of Near-infrared Spectrograph onboard JWST opens a new window to examine this spectacular outflow through Pa$α$ emission line with $\sim$3$\times$ better spatial resolution than previous work. The morphology and kinematics of the Pa$α$ nebula confirm the existence of a bipolar outflow extending on a scale of $\sim$17$\times$14 kpc and with a velocity reaching $\sim$1100 km s$^{-1}$. The higher spatial resolution of our new observation leads to more reliable measurements of outflow kinematics. Considering only the spatially resolved outflow and assuming an electron density of 100 cm$^{-2}$, the mass, momentum and kinetic energy outflow rates are $\sim$50-210 M$_{\odot}$ yr$^{-1}$, $\sim$0.3-1.7$\times$10$^{36}$ dynes ($\sim$14-78\% of the quasar photon momentum flux) and $\sim$0.16-1.27$\times$10$^{44}$ erg s$^{-1}$ ($\sim$0.02-0.20\% of the quasar bolometric luminosity), respectively. The local instantaneous outflow rates generally decrease radially. We infer that the quasar is powerful enough to drive the outflow, while stellar processes cannot be overlooked as a contributing energy source. The mass outflow rate is $\sim$0.4-1.5 times the star formation rate, and the ratio of kinetic energy outflow rate to the quasar bolometric luminosity is comparable to the minimum value required for negative quasar feedback in simulations. This outflow may help regulate the star formation activity within the system to some extent.

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Combined JWST-MUSE Integral Field Spectroscopy of the Most Luminous Quasar in the Local Universe, PDS 456

Fast accreting, extremely luminous quasars contribute heavily to the feedback process within galaxies. While these systems are most common at cosmic noon ($z\sim2$), here we choose to study PDS 456, an extremely luminous ($L_{bol}\sim 10^{47}$ erg s$^{-1}$) but nearby ($z\sim0.185$) quasar where the physics of feedback can be studied in greater detail. We present the results from our analysis of the JWST MIRI/MRS integral field spectroscopic (IFS) data of this object. The extreme brightness of PDS 456 makes it challenging to study the extended emission even in this nearby object. MIRI/MRS instrumental effects are mitigated by using complementary NIRSpec and MUSE IFS data cubes. We show clear evidence of a multiphase gas outflow extending up to 15 kpc from the central source. This includes emission from warm molecular (H$_2$ $ν$ = 0 $-$ 0 and 1 $-$ 0) and ionized (e.g. Pa$α$, [O III], [Ne III], [Ne VI]) gas with typical blueshifted velocities down to $-500$ km s$^{-1}$. We are also able to probe the nuclear dust emission in this source through silicate and PAH emission features but are unable to spatially resolve it. Our results are consistent with this powerful quasar driving a radiatively driven wind over a broad range of distances and altering the ionization structure of the host galaxy.

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The Outflowing [OII] Nebulae of Compact Starburst Galaxies at z $\sim$ 0.5

High-velocity outflows are ubiquitous in compact, massive (M$_* \sim$ 10$^{11}$ M$_{\odot}$), z $\sim$ 0.5 galaxies with extreme star formation surface densities ($Σ_{SFR} \sim$ 2000 M$_{\odot}$ yr$^{-1}$ kpc$^{-2}$). We have previously detected and characterized these outflows using MgII absorption lines. To probe their full extent, we present Keck/KCWI integral field spectroscopy of the [OII] and MgII emission nebulae surrounding all of the 12 galaxies in this study. We find that [OII] is more effective than MgII in tracing low surface brightness, extended emission in these galaxies. The [OII] nebulae are spatially extended beyond the stars, with radial extent R$_{90}$ between 10 and 40 kpc. The nebulae exhibit non-gravitational motions, indicating galactic outflows with maximum blueshifted velocities ranging from -335 to -1920 km s$^{-1}$. The outflow kinematics correlate with the bursty star formation histories of these galaxies. Galaxies with the most recent bursts of star formation (within the last $<$ 3 Myr) exhibit the highest central velocity dispersions ($σ>$ 400 km s$^{-1}$), while the oldest bursts have the lowest-velocity outflows. Many galaxies exhibit both high-velocity cores and more extended, slower-moving gas indicative of multiple outflow episodes. The slower, larger outflows occurred earlier and have decelerated as they propagate into the CGM and mix on timescales $>$ 50 Myr.

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[OIII] 5007 emissions in extremely red quasars (ERQs) are compact

``Extremely red quasars'' (ERQs) are a non-radio-selected, intrinsically luminous population of quasars at cosmic noon selected by their extremely red colour from rest-frame UV to mid-IR. ERQs are uniquely associated with exceptionally broad and blueshifted [OIII] 5007 emission reaching speeds >6000 km s^-1. We obtained adaptive optics integral-field spectroscopic observations using Keck/OSIRIS and Gemini/NIFS of a sample of 10 ERQs with bolometric luminosities (10^47.0-10^47.9) erg s^-1 at z ~(2.3-3.0). The goal is to measure the sizes and spatially-resolved kinematics of the [OIII]-emitting regions. We study the surface brightness maps and aperture-extracted spectra and model the point-spread functions. We identify signs of merger activities in the continuum emissions. We identify physically distinct [OIII] kinematic components that are bimodal and respectively trace ERQ-driven outflows of velocity dispersion >250 km s^-1 and dynamically quiescent interstellar media. We find that the ERQ-driven ionized outflows are typically at ~1 kpc scales whereas the quiescent ionized gas extend to a few kpc. Compared to normal quasars the extremely fast ERQ-driven [OIII] outflows tend to be more compact, supporting the notion that ERQs are in a young stage of quasar/galaxy evolution and represent systems with unique physical conditions beyond orientation differences with normal quasar populations. The kinematically quiescent [OIII] emissions in ERQs tend to be spatially-resolved but less extended than in normal quasars, which can be explained by global and patchy dust obscuration. The hint of ionization cones suggests some of the obscuration can be partially explained by a patchy torus.

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JWST ERS Program Q3D: The pitfalls of virial BH mass constraints shown in a z = 3 quasar with an ultramassive host

We present JWST MIRI/NIRSpec observations of the extremely red quasar SDSS J165202.64+172852.3 at z~3, one of the most luminous quasars known to date, driving powerful outflows and hosting a clumpy starburst, amidst several interacting companions. We estimate the black hole (BH) mass of the system based on the broad H$α$ and H$β$ lines, as well as the Pa$β$ emission in the IR and MgII in the UV. We recover a very broad range of mass estimates, with constraints ranging between log $M_{\rm BH}$=9 and 10.1, which is exacerbated if imposing a uniform BLR geometry at all wavelengths. Several factors may contribute to the large spread: measurement uncertainties (insufficient sensitivity to detect the broadest component of the faint Pa$β$ line, spectral blending, ambiguities in the broad/narrow component distinction), lack of virial equilibrium (in a system characterised by powerful outflows and rapid accretion), and uncertainties on the luminosity-inferred size of the broad line region, a.o. given central dust obscuration. We constrain the stellar mass via SED fitting, suggesting the host to be extremely massive at $10^{12.8\pm 0.5} M_\odot$ - ~2 dex above the characteristic mass of the Schechter fit to the z=3 stellar mass function. Notably, J1652's central BH might be interpreted as being either undermassive, overmassive, or in line with the BH mass-stellar mass relation, depending on the choice of assumptions. The recovered Eddington ratio varies accordingly, but exceeds 10% in any case. We put our results into context by providing an extensive overview and discussion of recent literature results and their associated assumptions. Our findings provide an important demonstration of the uncertainties inherent in virial BH mass estimates, which are of particular relevance in the JWST era given the growing number of studies on rapidly accreting quasars at high redshift.

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Fast Outflows and Luminous He II Emission in Dwarf Galaxies with AGN

While stellar processes are believed to be the main source of feedback in dwarf galaxies, the accumulating discoveries of AGN in dwarf galaxies over recent years arouse the interest to also consider AGN feedback in them. Fast, AGN-driven outflows, a major mechanism of AGN feedback, have indeed been discovered in dwarf galaxies and may be powerful enough to provide feedback to their dwarf hosts. In this paper, we search for outflows traced by the blueshifted ultraviolet absorption features in three dwarf galaxies with AGN from the sample examined in our previous ground-based study. We confirm outflows traced by blueshifted absorption features in two objects and tentatively detect an outflow in the third object. In one object where the outflow is clearly detected in multiple species, photoionization modeling suggests that this outflow is located $\sim$0.5 kpc from the AGN, implying a galactic-scale impact. This outflow is much faster and possesses higher kinetic energy outflow rate than starburst-driven outflows in sources with similar star formation rates, and is likely energetic enough to provide negative feedback to its host galaxy as predicted by simulations. Much broader ($\sim$4000 km s$^{-1}$) absorption features are also discovered in this object which may have the same origin as that of broad absorption lines in quasars. Additionally, strong He II $λ$1640 emission is detected in both objects where the transition falls in the wavelength coverage, and is consistent with an AGN origin. In one of these two objects, blueshifted He II emission line is clearly detected, likely tracing a highly-ionized AGN wind.

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JWST discovers an AGN ionization cone but only weak radiative-driven feedback in a powerful $z$$\approx$3.5 radio-loud AGN

We present the first results from a JWST program studying the role played by powerful radio jets in the evolution of the most massive galaxies at the onset of Cosmic Noon. Using NIRSpec integral field spectroscopy, we detect 24 rest-frame optical emission lines from the $z=3.5892$ radio galaxy 4C+19.71. 4C+19.71 contains one of the most energetic radio jets known, making it perfect for testing radio-mode feedback on the interstellar medium (ISM) of a $M_{\star}\sim10^{11}\,\rm M_{\odot}$ galaxy. The rich spectrum enables line ratio diagnostics showing that the radiation from the active galactic nucleus (AGN) dominates the ionization of the entire ISM out to at least $25\,$kpc, the edge of the detection. Sub-kpc resolution reveals filamentary structures and emission blobs in the warm ionized ISM distributed on scales of $\sim5$ to $\sim20\,$kpc. A large fraction of the extended gaseous nebula is located near the systemic velocity. This nebula may thus be the patchy ISM which is illuminated by the AGN after the passage of the jet. A radiatively-driven outflow is observed within $\sim5\,$kpc from the nucleus. The inefficient coupling ($\lesssim 10^{-4}$) between this outflow and the quasar and the lack of extreme gas motions on galactic scales are inconsistent with other high-$z$ powerful quasars. Combining our data with ground-based studies, we conclude that only a minor fraction of the feedback processes is happening on $<25\,$kpc scales.

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Ionized Gas Extended Over 40 kpc in an Odd Radio Circle Host Galaxy

A new class of extragalactic astronomical sources discovered in 2021, named Odd Radio Circles (ORCs, Norris et al. 2021), are large rings of faint, diffuse radio continuum emission spanning ~1 arcminute on the sky. Galaxies at the centers of several ORCs have photometric redshifts of z~0.3-0.6, implying physical scales of several 100 kiloparsecs in diameter for the radio emission, the origin of which is unknown. Here we report spectroscopic data on an ORC including strong [OII] emission tracing ionized gas in the central galaxy of ORC4 at z=0.4512. The physical extent of the [OII] emission is ~40 kpc in diameter, larger than expected for a typical early-type galaxy (Pandya et al, 2017) but an order of magnitude smaller than the large-scale radio continuum emission. We detect a ~200 km/s velocity gradient across the [OII] nebula, as well as a high velocity dispersion of ~180 km/s. The [OII] equivalent width (EW, ~50 Ang) is extremely high for a quiescent galaxy. The morphology, kinematics, and strength of the [OII] emission are consistent with the infall of shock ionized gas near the galaxy, following a larger-scale, outward moving shock driven by a galactic wind. Both the extended optical and radio emission, while observed on very different scales, may therefore result from the same dramatic event.

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