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The James Webb Space Telescope opens a new window to directly probe luminous quasars powered by billion solar mass black holes in the Epoch of Reionization and their coevolution with massive galaxies with unprecedented details. In this paper, we report the first results from a deep NIRSpec integral field unit spectroscopic study of a quasar at z = 7.5. We obtain a bolometric luminosity of ∼1.8 × 1047 erg s−1 and a black hole mass of ∼0.7–2.5 × 109 M ⊙ based on the H β emission line in the quasar spectrum. We discover ∼2 kpc scale, highly blueshifted (∼−870 km s−1) and broad (∼1400 km s−1) [O iii ] line emission after the quasar point-spread function has been subtracted. Such line emission most likely originates from a fast, quasar-driven outflow, the earliest one at galactic scales known so far. The dynamical properties of this outflow fall within the typical ranges of quasar-driven outflows at lower redshift, and the outflow may be fast enough to reach the circumgalactic medium. Combining both the extended and nuclear outflow together, the mass outflow rate, ∼300 M ⊙ yr−1, is ∼60%–380% of the star formation rate of the quasar host galaxy, suggesting that the outflow may expel a significant amount of gas from the inner region of the galaxy. The kinetic energy outflow rate, ∼3.6 × 1044 erg s−1, is ∼0.2% of the quasar bolometric luminosity, which is comparable to the minimum value required for negative feedback based on simulation predictions. The dynamical timescale of the extended outflow is ∼1.7 Myr, consistent with the typical quasar lifetime in this era. [ABSTRACT FROM AUTHOR]

We introduce an improved method for decomposing the emission of active galactic nuclei (AGN) and their host galaxies using templates from principal component analysis (PCA). This approach integrates prior information from PCA with a penalized pixel fitting mechanism that improves the precision and effectiveness of the decomposition process. Specifically, we have reduced the degeneracy and overfitting in AGN host decomposition, particularly for those with low signal-to-noise ratios (SNRs), where traditional methods tend to fail. By applying our method to 76,565 Sloan Digital Sky Survey Data Release 16 quasars with z < 0.8, we achieve a success rate of ≈94%, thus establishing the largest host-decomposed spectral catalog of quasars to date. Our fitting results consider the impact of the host galaxy on the overestimation of the AGN luminosity and black hole mass (M BH). Furthermore, we obtained stellar velocity dispersion (σ ⋆) measurements for 4137 quasars. The slope of the M BH− σ ⋆ relation in this subsample is generally consistent with previous quasar studies beyond the local Universe. Our method provides a robust and efficient approach to disentangle the AGN and host galaxy components across a wide range of SNRs and redshifts. [ABSTRACT FROM AUTHOR]

Circumnuclear star formation (SF) is generally seen in galaxies hosting active galactic nuclei (AGN); however, the connection between the AGN activity and SF in them is less well understood. To explore this connection on scales of a few tens of parsecs to a few tens of kiloparsecs and larger, we carried out an investigation of SF in seven Seyfert-type AGN and one low-ionization nuclear emission-line region galaxy, using observations with the Ultraviolet Imaging Telescope on board AstroSat in the near-ultraviolet (2000–3000 Å) and far-ultraviolet (1300−1800 Å) bands. A total of 1742 star-forming regions were identified, having size scales of 0.010–63.642 kpc2. Considering all the galaxies, we found a positive correlation between their total surface density of SF (ΣSFR) and extinction. For five galaxies, namely NGC 1365, NGC 4051, NGC 4321, NGC 5033, and NGC 6814, we found a gradual decrease of both extinction and ΣSFR from the centre to the outer regions. Four sources are found to lie in the main sequence of star-forming galaxies, and the other four lie away from it. We found the ratio of the star formation rate (SFR) in the nuclear region to the total SFR to be positively correlated with the Eddington ratio. This points to the influence of AGN in enhancing the SF characteristics of the hosts. However, the impact is dominant only in the central nuclear region and has no significant effect on the larger scales probed in this work. [ABSTRACT FROM AUTHOR]

We have characterized the ionized, neutral, and warm molecular gas kinematics in the Seyfert 1 galaxy NGC 3227 using observations from the Hubble Space Telescope Space Telescope Imaging Spectrograph, Apache Point Observatory's Kitt Peak Ohio State Multi-Object Spectrograph, Gemini-North's Near-Infrared Integral Field Spectrometer, and the Atacama Large Millimeter/submillimeter Array. We fit multiple Gaussians to several spatially resolved emission lines observed with long-slit and integral-field spectroscopy and isolate the kinematics based on apparent rotational and outflowing motions. We use the kinematics to determine an orientation for the bicone along which the outflows travel and find that the biconical structure has an inclination of 40 − 4 + 5 ° from our line of sight and a half-opening angle with an inner and outer boundary of 47 − 2 + 6 ° and 68 − 1 + 1 °, respectively. We observe ionized outflows traveling 500 km s−1 at distances up to 7″ (800 pc) from the supermassive black hole (SMBH) and disturbed ionized gas up to a distance of 15″ (1.7 kpc). Our analysis reveals that the ionized outflows are launched from within 20 pc of the SMBH, at the same location as a bridge of cold gas across the nucleus detected in Atacama Large Millimeter/submillimeter Array CO(2–1) observations. We measure a turnover radius where the gas starts decelerating at a distance of 26 ± 6 pc from the active galactic nucleus. Compared to a turnover radius in the range of 31−63 pc from a radiative driving model, we confirm that radiative driving is the dominant acceleration mechanism for the narrow-line region outflows in NGC 3227. [ABSTRACT FROM AUTHOR]

Jetted active galactic nuclei (AGN) hosting extended photoionized nebulae provide us with a unique view of the timescales associated with AGN activity. Here, we present a new green bean galaxy at z = 0.304458 ± 0.000007 with large-scale jet-induced radio emission. The spectral energy distributions of the radio components show steep spectral indices (α = −0.85 to −0.92 for the extended regions, and α = −1.02 for the faint radio core), and spectral age modeling of the extended radio emission indicates that the lobes are >6 Myr old. It is unclear whether the jet is active, or is a remnant with an off-time of 2–3 Myr. Several detached clouds lie around the host galaxy up to 37.8 kpc away from the nucleus, and their ionization profile indicates a decline (∼2 dex) in the AGN ionizing photon production over the past ∼0.15 Myr. Furthermore, we measure a blueshift for one of the clouds that is spatially coincident with the path of the radio jet. The cloud is likely illuminated by the photoionizing AGN, and potentially underwent an interaction with the relativistic jet. Our multiwavelength analysis suggests that RGB1 was in a phase of jet production prior to the radiatively efficient accretion phase traced by the detached cloud emission. It is unclear whether RGB1 transitioned into a low-excitation radio galaxy or an inactive galaxy over the past ∼0.15 Myr, or whether the extended radio and optical emission trace distinct accretion phases that occurred in succession. [ABSTRACT FROM AUTHOR]

Previous X-ray works on Mrk 1239 have revealed a complex narrow-line Seyfert 1 that exhibits substantial absorption and strong emission from both collisionally ionized and photoionized plasmas. Here, we report on deep-pointed observations with XMM-Newton and NuSTAR, along with Swift monitoring, to understand the 0.3–30 keV continuum emission and the central engine geometry. A strong X-ray flare, where the AGN brightens by a factor of 5 in ∼30 ks, is captured between 4 and 30 keV and can be attributed to a brightening of the primary continuum. However, the lack of any variability below ∼3 keV on long or short timescales requires complete absorption of the AGN continuum with a neutral medium of column density ∼1023.5 cm−2. The timing and spectral properties are consistent with a blurred reflection interpretation for the primary emission. The variability and presence of a Compton hump disfavors ionized partial covering. The neutral absorber, if outflowing, could be crashing into the surrounding medium and interstellar medium to produce the low-energy continuum and collisionally ionized emission. Scattered emission off the inner torus could produce the photoionized emission. The intricate scenario is demanded by the data and highlights the complexity of the environment that is normally invisible when overwhelmed by the AGN continuum. Objects like Mrk 1239 serve as important sources for unveiling the interface between the AGN and host galaxy environments. [ABSTRACT FROM AUTHOR]

The Photometric objects Around Cosmic webs (PAC) approach developed in Xu et al. has the advantage of making full use of spectroscopic and deeper photometric surveys. With the merits of PAC, the excess surface density n ¯ 2 w p of neighboring galaxies can be measured down to stellar mass 1010.80 M ⊙ around quasars at redshift 0.8 < z s < 1.0, with the data from the Sloan Digital Sky Survey IV extended Baryon Oscillation Spectroscopic Survey and the Dark Energy Spectroscopic Instrument Legacy Imaging Surveys. We find that n ¯ 2 w p generally increases quite steeply with the decrease of the separation. Using the subhalo abundance-matching method, we can accurately model the n ¯ 2 w p both on small and large scales. We show that the steep increase of n ¯ 2 w p toward the quasars requires that a large fraction f sate = 0.29 − 0.06 + 0.05 of quasars should be satellites in massive halos, and we find that this fraction measurement is insensitive to the assumptions of our modeling. This high satellite fraction indicates that the subhalos have nearly the same probability of hosting quasars as the halos for the same (infall) halo mass and that the large-scale environment has negligible effect on the quasar activity. We show that even with this high satellite fraction, each massive halo on average does not host more than one satellite quasar, due to the sparsity of quasars. [ABSTRACT FROM AUTHOR]

We present the first systematic search for UV signatures from radio source-driven active galactic nuclei (AGN) feedback in Compact Steep Spectrum (CSS) radio galaxies. Owing to their characteristic sub-galactic jets (1–20 kpc projected linear sizes), CSS hosts are excellent laboratories for probing galaxy scale feedback via jet-triggered star formation. The sample consists of seven powerful CSS galaxies, and two galaxies host to radio sources >20 kpc as the control, at low to intermediate redshifts (z < 0.6). Our new Hubble Space Telescope images show extended UV continuum emission in six out of seven CSS galaxies, with five CSS hosts exhibiting UV knots cospatial and aligned along the radio-jet axis. Young (≲ 10 Myr), massive (≳ 5 M ⊙) stellar populations are likely to be the dominant source of the blue excess emission in radio galaxies at these redshifts. Hence, the radio-aligned UV regions could be attributed to jet-induced starbursts. Lower near-UV star formation rates compared to other indicators suggest low scattered AGN light contribution to the observed UV. Dust attenuation of UV emission appears unlikely from high internal extinction correction estimates in most sources. Comparison with evolutionary synthesis models shows that our observations are consistent with recent (∼1−8 Myr old) star-forming activity likely triggered by current or an earlier episode of radio emission, or by a confined radio source that has frustrated growth, due to a dense environment. While follow-up spectroscopic and polarized light observations are needed to constrain the activity-related components in the observed UV, the detection of jet-induced star formation is a confirmation of an important prediction of the jet feedback paradigm. [ABSTRACT FROM AUTHOR]

We measure the bolometric luminosity of a complete and unbiased 12 μ m-selected sample of active galactic nuclei (AGN) in the local Universe. For each galaxy, we used a 10-band radio-to-X-ray spectral energy distribution (SED) to isolate the genuine AGN continuum in each band, including subarcsecond measurements where available, and correcting those contaminated by the host galaxy. We derive the median SED of Seyfert type 1 AGN, Seyferts with hidden broad lines (HBLs), Seyferts of type 2, and LINER nuclei in our sample. The median Seyfert 1 SED shows the characteristic blue bump feature in the UV, but nevertheless, the largest contribution to the bolometric luminosity comes from the IR and X-ray continua. The median SEDs of both HBL and type 2 AGN are affected by starlight contamination in the optical/UV. The median SED of HBL AGN is consistent with that of Seyfert 1s, when an extinction of A V ∼ 1.2 mag is applied. The comprehensive SEDs allowed us to measure accurate bolometric luminosities and derive robust bolometric corrections for the different tracers. The 12 μ m and K -band nuclear luminosities have good linear correlations with the bolometric luminosity, similar to those in the X-rays. We derive bolometric corrections for either continuum bands (K band, 12 μ m, 2–10 keV, and 14–195 keV) or narrow emission lines (mid-IR high-ionization lines of [O iv ] and [Ne v ] and optical [O iii ] 5007 Å) as well as for combinations of IR continuum and line emission. A combination of continuum plus line emission accurately predicts the bolometric luminosity up to quasar luminosities (∼1046 erg s−1). [ABSTRACT FROM AUTHOR]

We present Chandra ACIS-S imaging spectroscopy results of the extended (1.″5–8″, 300–1600 pc) hard X-ray emission of NGC 5728, the host galaxy of a Compton-thick active galactic nucleus. We find spectrally and spatially resolved features in the Fe K α complex (5.0–7.5 keV) redward and blueward of the neutral Fe line at 6.4 keV in the extended narrow-line region bicone. A simple phenomenological fit of a power law plus Gaussians gives a significance of 5.4 σ and 3.7 σ for the red and blue wings, respectively. Fits to a suite of physically consistent models confirm a significance of ≥3 σ for the red wing. The significance of the blue wing may be diminished by the presence of rest-frame highly ionized Fe xxv and Fe xxvi lines (1.4 σ –3.7 σ range). A detailed investigation of the Chandra ACIS-S point-spread function and comparison with the observed morphology demonstrates that these red and blue wings are radially extended (∼5″, ∼1 kpc) along the optical bicone axis. If the wing emission is due solely to redshifted and blueshifted high-velocity neutral Fe K α, then the implied line-of-sight velocities are +/− ∼0.1 c, and their fluxes are consistent with being equal. A symmetric high-velocity outflow is then a viable explanation. This outflow has deprojected velocities ∼100 times larger than the outflows detected in optical spectroscopic studies, potentially dominating the kinetic feedback power. [ABSTRACT FROM AUTHOR]

The nearby dwarf galaxy POX 52 at z = 0.021 hosts an active galactic nucleus (AGN) with a black hole (BH) mass of M BH ∼ 105–6 M ⊙ and an Eddington ratio of ∼0.1–1. This object provides the rare opportunity to study both AGN and host-galaxy properties in a low-mass highly accreting system. To do so, we collected its multiwavelength data from X-ray to radio. First, we construct a spectral energy distribution, and by fitting it with AGN and host-galaxy components, we constrain AGN-disk and dust-torus components. Then, while considering the AGN-disk emission, we decompose optical Hubble Space Telescope images. As a result, it is found that a classical bulge component is probably present, and its mass (M bulge) is consistent with an expected value from a local relation. Lastly, we analyze new quasi-simultaneous X-ray (0.2–30 keV) data obtained by the Nuclear Spectroscopic Telescope Array and XMM-Newton. The X-ray spectrum can be reproduced by multicolor blackbody, warm and hot coronae, and disk and torus reflection components. Based on this, the spin is estimated to be a spin = 0.998−0.814, which could suggest that most of the current BH mass was achieved by prolonged mass accretion. Given the presence of the bulge, POX 52 would have undergone a galaxy merger, while the M BH– M bulge relation and the inferred prolonged accretion could suggest that AGN feedback occurred. Regarding the AGN structure, the spectral slope of the hot corona, its relative strength to the bolometric emission, and the torus structure are found to be consistent with Eddington-ratio dependencies found for nearby AGNs. [ABSTRACT FROM AUTHOR]

The first quasars at the Reionisation Epoch, z ∼ 6-7.5, probe the early stages of supermassive black holes and host galaxy assembly. In this paper, we present recent results, exploiting VLT, ALMA and NOEMA observations, that allow us to constrain the onset of strong black hole feedback, the dust properties and star formation rates in high redshift quasars with unprecedented accuracy. These results highlight the strategic importance of ALMA high frequency (i.e. Band 9 and 8) observations to obtain a reliable overview of the host galaxy and supermassive black hole growth out to the highest redshifts. [ABSTRACT FROM AUTHOR]

We study the morphologies and structures of 57 dwarf galaxies that are representative of the general population of dwarf galaxies and compare their demographics to a sample of dwarf galaxies hosting optically selected active galactic nuclei (AGNs). The two samples span the same galaxy stellar mass (109 ≲ M ⋆/ M ⊙ ≲ 109.5) and color range, and the observations are well-matched in physical resolution. The fractions of irregular galaxies (14%) and early types/ellipticals (∼18%) are nearly identical among the two samples. However, among galaxies with disks (the majority of each sample), the AGN hosts almost always have a detectable (pseudo)bulge, while a large fraction of the non-AGN hosts are pure disk galaxies with no detectable (pseudo)bulge. Central point sources of light consistent with nuclear star clusters are detected in many of the non-AGN hosts. In contrast, central point sources detected in the AGN hosts are, on average, more than 2 orders of magnitude more luminous, suggesting the point sources in these objects are dominated by AGN light. The preference for (pseudo)bulges in dwarf AGN hosts may inform searches for massive black holes in dwarf galaxies and attempts to constrain the black hole occupation fraction, which, in turn, has implications for our understanding of black hole seeding mechanisms. [ABSTRACT FROM AUTHOR]

JWST has revealed a ubiquitous population of “little red dots” (LRDs) at z ≳ 4, selected via their red rest-frame optical emission and compact morphologies. They are thought to be reddened by dust, whether in tori of active galactic nuclei (AGNs) or the interstellar medium, though none have direct dust detections to date. Informed by the average characteristics of 675 LRDs drawn from the literature, we provide ballpark constraints on the dust characteristics of the LRD population and estimate they have average dust masses of $\langle {M}_{\mathrm{dust}}\rangle =({1.6}_{-0.9}^{+4.8})\times {10}^{4}$ M _⊙ , luminosities of $\langle {L}_{\mathrm{IR}}\rangle =({8}_{-5}^{+3})\times {10}^{10}$ L _⊙ , and temperatures of $\langle {T}_{\mathrm{dust}}\rangle ={110}_{-36}^{+21}$ K. Notably, the spectral energy distributions are thought to peak at ∼100 K (rest-frame 20–30 μ m) regardless of heating mechanism, whether AGN or star formation. LRDs’ compact sizes R _eff ∼ 100 pc are the dominant factor contributing to their low estimated dust masses. Our predictions likely mean LRDs have, on average, a submillimeter emission factor of ∼100× fainter than current Atacama Large Millimeter/submillimeter Array limits provide. The star-to-dust ratio is a factor ∼100× larger than expected from dust formation models if one assumes the rest-optical light is dominated by stars; this suggests stars do not dominate. Despite their high apparent volume density, LRDs contribute negligibly (0.1%) to the cosmic dust budget at z ≳ 4 due to their low dust masses.

In the last decade, there have been several discoveries of active galactic nuclei (AGN) in dwarf galaxies including an AGN in an ultracompact dwarf galaxy with a black hole mass >10 ^6 M _⊙ . However, finding a supermassive black hole (SMBH) in a dwarf low surface brightness (LSB) galaxy is rare. We report the discovery of a Seyfert type 2 class AGN that is associated with a nuclear SMBH of mass ∼6.5 × 10 ^6 M _⊙ in a dwarf LSB galaxy ( μ _0, _r > 23.8 mag arcsec ^−2 ) that we denote by MJ0818+2257. The galaxy was previously thought to be an outlying emission blob around the large spiral galaxy LEDA 1678924. In our current analysis, which includes the detection of the optical counterpart of MJ0818+2257, we study its ionized gas kinematics and find that the dynamical mass within the ionized gas disk is ∼5.3 × 10 ^9 M _⊙ . This is comparable to its stellar mass, which is ∼3 × 10 ^9 M _⊙ , and suggests that MJ0818+2257 is moderately dark matter dominated within the stellar disk. The SMBH-mass-to-galaxy-stellar-mass ratio is M _BH / M (*) > 0.022, which is high compared to disk galaxies. Our detection of an SMBH in a bulgeless LSB dwarf galaxy raises questions about the growth of SMBHs in low-luminosity galaxies and suggests the possibility of detecting heavy seed black holes from early epochs in LSB dwarf galaxies in the low-redshift Universe.

The identification of red, apparently massive galaxies at z > 7 in early James Webb Space Telescope (JWST) photometry suggests a strongly accelerated time line compared to standard models of galaxy growth. A major uncertainty in the interpretation is whether the red colors are caused by evolved stellar populations, dust, or other effects such as emission lines or active galactic nuclei (AGNs). Here we show that three of the massive galaxy candidates at z = 6.7–8.4 have prominent Balmer breaks in JWST/NIRSpec spectroscopy from the RUBIES program. The Balmer breaks demonstrate unambiguously that stellar emission dominates at λ _rest = 0.4 μ m and require formation histories extending hundreds of millions of years into the past in galaxies only 600–800 Myr after the big bang. Two of the three galaxies also show broad Balmer lines, with H β FWHM > 2500 km s ^−1 , suggesting that dust-reddened AGNs contribute to, or even dominate, the spectral energy distributions of these galaxies at λ _rest ≳ 0.6 μ m. All three galaxies have relatively narrow [O iii ] lines, seemingly ruling out a high-mass interpretation if the lines arise in dynamically relaxed, inclined disks. Yet the inferred masses also remain highly uncertain. We model the high-quality spectra using Prospector to decompose the continuum into stellar and AGN components and explore limiting cases in stellar/AGN contribution. This produces a wide range of possible stellar masses, spanning M _⋆ ∼ 10 ^9 −10 ^11 M _⊙ . Nevertheless, all fits suggest a very early and rapid formation, most of which follow with a truncation in star formation. Potential origins and evolutionary tracks for these objects are discussed, from the cores of massive galaxies to low-mass galaxies with overmassive black holes. Intriguingly, we find all of these explanations to be incomplete; deeper and redder data are needed to understand the physics of these systems.

JWST is producing high-quality rest-frame optical and UV spectra of faint galaxies at z > 4 for the first time, challenging models of galaxy and stellar populations. One galaxy recently observed at z = 5.943, GS9422, has nebular line and UV continuum emission that appears to require a high ionizing photon production efficiency. This has been explained with an exotic stellar initial mass function (IMF; Cameron et al. 2023a), 10–30x more top-heavy than a Salpeter IMF. Here we suggest an alternate explanation to this exotic IMF. We use a new flexible neural net emulator for CLOUDY, Cue , to infer the shape of the ionizing spectrum directly from the observed emission line fluxes. By describing the ionizing spectrum with a piecewise power law, Cue is agnostic to the source of the ionizing photons. Cue finds that the ionizing radiation from GS9422 can be approximated by a double power law characterized by $\tfrac{{Q}_{{\rm{HeII}}}}{{Q}_{{\rm{H}}}}=-1.5$ , which can be interpreted as a combination of young, metal-poor stars and a low-luminosity active galactic nucleus with F _ν ∝ λ ^2 in a 65%/35% ratio. This suggests a significantly lower nebular continuum contribution to the observed UV flux (24%) than a top-heavy IMF (≳80%), and hence, necessitates a damped Ly α absorber to explain the continuum turnover bluewards of ∼1400 Å. While current data cannot rule out either scenario, given the immense impact the proposed top-heavy IMF would have on models of galaxy formation, it is important to propose viable alternative explanations and to further investigate the nature of peculiar high- z nebular emitters.

Recent observations of changing-look active galactic nuclei (AGNs) hint at a frequency of accretion activity not fully explained by tidal disruption events (TDEs) stemming from relaxation processes in nuclear star clusters (NSCs), traditionally estimated to occur at rates of 10 ^−4 –10 ^−5 yr ^−1 per galaxy. In this Letter, we propose an enhanced TDE rate through the AGN disk capture process, presenting a viable explanation for the frequent transitions observed in changing-look AGNs. Specifically, we investigate the interaction between the accretion disk and retrograde stars within NSCs, resulting in the rapid occurrence of TDEs within a condensed time frame. Through detailed calculations, we derive the time-dependent TDE rates for both relaxation-induced TDE and disk-captured TDE. Our analysis reveals that TDEs triggered by the disk capture process can notably amplify the TDE rate by several orders of magnitude during the AGN phase. This mechanism offers a potential explanation for the enhanced high-energy variability characteristic of changing-look AGNs.

Spectral energy distributions (SEDs) from X-ray to far-infrared (FIR) wavelengths are presented for a sample of 1246 X-ray-luminous active galactic nuclei (AGNs; L 0.5–10 keV > 1043 erg s−1), with z spec < 1.2, selected from Stripe 82X, COSMOS, and GOODS-N/S. The rest-frame SEDs show a wide spread (∼2.5 dex) in the relative strengths of broad continuum features at X-ray, ultraviolet (UV), mid-infrared (MIR), and FIR wavelengths. A linear correlation (log–log slope of 0.7 ± 0.04) is found between L MIR and L X. There is significant scatter in the relation between the L UV and L X owing to heavy obscuration; however, the most luminous and unobscured AGNs show a linear correlation (log–log slope of 0.8 ± 0.06) in the relation above this scatter. The relation between L FIR and L X is predominantly flat, but with decreasing dispersion at L X > 1044 erg s−1. The ratio between the "galaxy-subtracted" bolometric luminosity and the intrinsic L X increases from a factor of ∼10 to 70 from log L bol/(erg s−1) = 44.5 to 46.5. Characteristic SED shapes have been determined by grouping AGNs based on relative strengths of the UV and MIR emission. The average L 1 μ m is constant for the majority of these SED shapes, while AGNs with the strongest UV and MIR emission have elevated L 1 μ m, consistent with the AGN emission dominating their SEDs at optical and near-infrared wavelengths. A strong correlation is found between the SED shape and both the L X and L bol, such that L bol/ L X = 20.4 ± 1.8, independent of the SED shape. This is consistent with an evolutionary scenario of increasing L bol with decreasing obscuration as the AGN blows away circumnuclear gas. [ABSTRACT FROM AUTHOR]

Massive galaxies formed most actively at redshifts z = 1–3 during the period known as "cosmic noon." Here we present an emission-line study of the extremely red quasar SDSSJ165202.64+172852.3's host galaxy at z = 2.94, based on observations with the Near Infrared Spectrograph integral field unit on board JWST. We use standard emission-line diagnostic ratios to map the sources of gas ionization across the host and a swarm of companion galaxies. The quasar dominates the photoionization, but we also discover shock-excited regions orthogonal to the ionization cone and the quasar-driven outflow. These shocks could be merger-induced or—more likely, given the presence of a powerful galactic-scale quasar outflow—these are signatures of wide-angle outflows that can reach parts of the galaxy that are not directly illuminated by the quasar. Finally, the kinematically narrow emission associated with the host galaxy presents as a collection of 1 kpc–scale clumps forming stars at a rate of at least 200 M ⊙ yr−1. The interstellar medium within these clumps shows high electron densities, reaching up to 3000 cm−3, with metallicities ranging from half to a third solar with a positive metallicity gradient, and V -band extinctions up to 3 mag. The star formation conditions are far more extreme in these regions than in local star-forming galaxies but consistent with those of massive galaxies at cosmic noon. The JWST observations simultaneously reveal an archetypal rapidly forming massive galaxy undergoing a merger, a clumpy starburst, an episode of obscured near-Eddington quasar activity, and an extremely powerful quasar outflow. [ABSTRACT FROM AUTHOR]

We present rest-frame ultraviolet images of six luminous quasars at z ∼ 4.8 obtained with the Hubble Space Telescope (HST). These quasars exhibit a wide range of star formation rates (SFRs) and lie in a wide range of environments. We carefully model and subtract the point-like quasar emission and investigate the morphology of the underlying host galaxies at kpc scales. The residual images allowed identification of potential companion sources, which enabled us to explore the role of galaxy merger scenarios in the coevolution of the quasars and their hosts. We also search for the mechanism driving extreme SFRs in three of the six quasars. We find that the rate of detection of potential companions to the host galaxies does not follow trends between high- and low-SFR sources; i.e., the HST imaging suggests that both high- and low-SFR sources are found in both dense and sparse galactic environments. The suggested role of major mergers driving extreme SFRs cannot be supported by the multiwavelength data in hand. Three of four companion sources, previously revealed by submillimeter observations, are not detected in the HST images of three of our quasars. An adapted high-resolution imaging strategy focused on high-SFR sources and extended to a larger quasar sample is required in order to determine the role of mergers in the processes of star formation and supermassive black hole growth at high redshift. [ABSTRACT FROM AUTHOR]

Mergers of galaxies are a ubiquitous phenomenon in the universe and represent a natural consequence of the "bottom-up" mass accumulation and galaxy evolution cosmological paradigm. It is generally accepted that the peak of active galactic nucleus (AGN) accretion activity occurs at nuclear separations of ≲10 kpc for major mergers. Here we present new NuSTAR and XMM-Newton observations for a subsample of mid-IR preselected dual AGN candidates in an effort to better constrain the column densities along the line of sight (LOS) for each system. Only one dual AGN candidate, J0841+0101, is detected as a single, unresolved source in the XMM-Newton and NuSTAR imaging, while the remaining three dual AGN candidates, J0122+0100, J1221+1137, and J1306+0735, are not detected with NuSTAR; if these nondetections are due to obscuration alone, these systems are consistent with being absorbed by column densities of log(N H/cm−2) ≥ 24.9, 24.6, and 24.3, which are roughly consistent with previously inferred column densities in these merging systems. In the case of J0841+0101, the analysis of the 0.3–30 keV spectra reveal an LOS column density of N H ≳ 1024 cm−2, significantly larger than the column densities previously reported for this system and demonstrating the importance of the higher signal-to-noise ratio XMM-Newton spectra and access to the >10 keV energies via NuSTAR. Though it is unclear if J0841+0101 truly hosts a dual AGN, these results are in agreement with the high obscuring columns expected in AGNs in late-stage mergers. [ABSTRACT FROM AUTHOR]

Despite the importance of feedback from active galactic nuclei (AGNs) in models of galaxy evolution, observational constraints on the influence of AGN feedback on star formation remain weak. To this end, we have compared the star formation trends of 279 low-redshift AGN galaxies with 558 inactive control galaxies using integral field unit spectroscopy from the Sloan Digital Sky Survey-IV Mapping Nearby Galaxies at Apache Point Observatory survey. With a Gaussian-process-based methodology, we reconstruct nonparametric star formation histories in spatially resolved spaxels covering the face of each galaxy. Based on the galaxy-wide star formation rates (SFRs) alone, we find no obvious signatures of AGN feedback. However, the AGN galaxies have significantly suppressed central (kiloparsec-scale) SFRs, lying up to a factor of 2 below those of the control galaxies, providing direct observational evidence of AGN feedback suppressing star formation. The suppression of central SFRs in the AGN galaxies began in the central regions ∼6 Gyr ago (redshift z ∼ 0.7), taking place over a few gigayears. A small subset of the AGN galaxies were rapidly driven to quiescence shortly before being observed (in the last 500 Myr), potentially indicating instances of AGN-driven feedback. More frequently, however, star formation continues in the AGN galaxies, with suppression primarily in the central regions. This is suggestive of a picture in which integrated (gigayear-timescale) AGN feedback can significantly affect central star formation, but may be inefficient in driving galaxy-wide quenching in low-redshift galaxies, instead leaving them in the green valley. [ABSTRACT FROM AUTHOR]

We present a study of the [O iii ] λ 5007 line profile in a subsample of eight active galactic nuclei (AGNs) and six non-AGNs in the optically selected green valley at z < 0.5 using long-slit spectroscopic observations obtained with the 11 m Southern African Large Telescope. Gaussian decomposition of the line profile was performed to study its different components. We observe that the AGN profiles are more complex than the non-AGN ones. In particular, in most AGNs (5/8) we detect a blue wing of the line. We derive the FWHM velocities of the wing and systemic component, and find that the AGNs show higher FWHM velocities than the non-AGNs in their core component. We also find that the AGNs show blue wings with a median velocity width of approximately 600 km s−1, and a velocity offset from the core component in the range −90 to −350 km s−1, in contrast to the non-AGN galaxies, where we do not detect blue wings in any of their [O iii ] λ 5007 line profiles. Using the spatial information in our spectra, we show that at least three of the outflow candidate galaxies have centrally driven gas outflows extending across the whole galaxy. Moreover, these are also the galaxies which are located on the main sequence of star formation, raising the possibility that the AGNs in our sample are influencing the star formation of their host galaxies (such as positive feedback). This is in agreement with our previous work where we studied the star formation, morphology, and stellar population properties of a sample of green valley AGNs and non-AGN galaxies. [ABSTRACT FROM AUTHOR]

The dichotomy between radio-loud (RL) and radio-quiet (RQ) active galactic nuclei (AGNs) is thought to be intrinsically related to radio jet production. This difference may be explained by the presence of a strong magnetic field (B -field) that enhances, or is the cause of, the accretion activity and the jet power. Here we report the first evidence of an intrinsic difference in the polarized dust emission cores of four RL and five RQ obscured AGNs using 89 μ m polarization with SOFIA/HAWC+. We find that the thermal polarized emission increases with the nuclear radio-loudness, R 20 = L 5GHz/ L 20 μ m. The dust emission cores of RL AGNs are measured to be polarized, ∼5%–11%, while RQ AGNs are unpolarized, <1%. For RQ AGNs, our results are consistent with the observed region being filled with an unmagnetized or highly turbulent disk and/or expanding outflow at scales of 5–130 pc from the AGNs. For RL AGNs, the measured 89 μ m polarization arises primarily from magnetically aligned dust grains associated with a 5–130 pc scale dusty obscuring structure with a toroidal B -field orientation highly offset, 65° ± 22°, with respect to the jet axis. Our results indicate that the size and strength of the B -fields surrounding the AGNs are intrinsically related to the strength of the jet power—the stronger the jet power is, the larger and stronger the toroidal B -field is. The detection of a ≤130 pc scale ordered toroidal B -field suggests that (a) the infalling gas that fuels RL AGNs is magnetized, (b) there is a magnetohydrodynamic wind that collimates the jet, and/or (c) the jet is able to magnetize its surroundings. [ABSTRACT FROM AUTHOR]

We perform X-ray spectral analyses to derive the characteristics (e.g., column density, X-ray luminosity) of ≈10,200 active galactic nuclei (AGNs) in the XMM-Spitzer Extragalactic Representative Volume Survey, which was designed to investigate the growth of supermassive black holes across a wide dynamic range of cosmic environments. Using physical torus models (e.g., Borus02) and a Bayesian approach, we uncover 22 representative Compton-thick (CT; N H > 1.5 × 1024 cm−2) AGN candidates with good signal-to-noise ratios as well as a large sample of 136 heavily obscured AGNs. We also find an increasing CT fraction (f CT) from low (z < 0.75) to high (z > 0.75) redshift. Our CT candidates tend to show hard X-ray spectral shapes and dust extinction in their spectral energy distribution fits, which may shed light on the connection between AGN obscuration and host-galaxy evolution. [ABSTRACT FROM AUTHOR]

We analyze the physical properties of eight X-ray-selected active galactic nuclei (AGNs) and one candidate protoquasar system (ADF22A1) in the z = 3.09 SSA22 protocluster by fitting their X-ray-to-IR spectral energy distributions (SEDs) using our SED-fitting code, Lightning (https://www.github.com/rafaeleufrasio/lightning). We recover star formation histories (SFHs) for seven of these systems which are well fit by composite stellar population plus AGN models. We find indications that four out of nine of the SSA22 AGN systems we study have host galaxies below the main sequence, with SFR/SFRMS ≤ −0.4. The remaining SSA22 systems, including ADF22A1, are consistent with obscured supermassive black hole (SMBH) growth in star-forming galaxies. We estimate the SMBH accretion rates and masses, and compare the properties and SFHs of the nine protocluster AGN systems with X-ray-detected AGN candidates in the Chandra Deep Fields (CDF), finding that the distributions of SMBH growth rates, star formation rates (SFRs), SMBH masses, and stellar masses for the protocluster AGNs are consistent with field AGNs. We constrain the ratio between the sample-averaged SSA22 SMBH mass and CDF SMBH mass to <1.41. While the AGNs are located near the density peaks of the protocluster, we find no statistically significant trends between the AGN or host-galaxy properties and their location in the protocluster. We interpret the similarity of the protocluster and field AGN populations together with existing results as suggesting that the protocluster and field AGNs coevolve with their hosts in the same ways, while AGN-triggering events are more likely in the protocluster. [ABSTRACT FROM AUTHOR]

We present new NOrthern Extended Millimeter Array (NOEMA) observations of the CO(2–1) emission in eight of the brightest Palomar-Green quasars at z ≲ 0.5 to investigate the role of active galactic nucleus (AGN) feedback in luminous quasars detected at low redshifts. We detect CO(2–1) emission in three objects, from which we derive CO luminosities, molecular gas masses and fractions, and gas depletion times. In combination with data available in the literature, we build a total sample of 138 local type 1 AGNs with CO(2–1) measurements. We compare the AGN properties with the host galaxy molecular gas properties, considering systems nondetected in CO emission. We find that the CO luminosity does not correlate with AGN luminosity and Eddington ratio, while the molecular gas fraction is weakly correlated with Eddington ratio. The type 1 AGNs can be roughly separated into two populations in terms of infrared-to-CO luminosity ratio, with one population presenting values typically found in normal star-forming systems, while the other having lower ratio values, comparable to those measured for starbursts. We find no evidence that AGN feedback rapidly quenches star formation in type 1 AGNs. Our results may imply an underlying the role of host galaxy gravitational instabilities or the fast inflow of cold gas in triggering AGN activity. [ABSTRACT FROM AUTHOR]

We used the Atacama Large Millimeter/submillimeter Array (ALMA) to map$^{12}$CO($J$ = 1-0), $^{12}$CO($J$ = 2-1), $^{12}$CO($J$ = 3-2), $^{13}$CO($J$= 2-1), and [CI]($^3P_1$-$^3P_0$) emission lines around the type 1 activegalactic nucleus (AGN) of NGC 7469 ($z = 0.0164$) at $\sim 100$ pc resolutions.The CO lines are bright both in the circumnuclear disk (central $\sim 300$ pc)and the surrounding starburst (SB) ring ($\sim 1$ kpc diameter), with twobright peaks on either side of the AGN. By contrast, the [CI]($^3P_1$-$^3P_0$)line is strongly peaked on the AGN. Consequently, the brightness temperatureratio of [CI]($^3P_1$-$^3P_0$) to $^{13}$CO(2-1) is $\sim 20$ at the AGN, ascompared to $\sim 2$ in the SB ring. Our local thermodynamic equilibrium (LTE)and non-LTE models indicate that the enhanced line ratios (or CI enhancement)are due to an elevated C$^0$/CO abundance ratio ($\sim 3-10$) and temperature($\sim 100-500$ K) around the AGN as compared to the SB ring (abundance ratio$\sim 1$, temperature $\lesssim 100$ K), which accords with the picture of theX-ray-dominated Region (XDR). Based on dynamical modelings, we also provideCO(1-0)-to- and [CI]($^3P_1$-$^3P_0$)-to-molecular mass conversion factors atthe central $\sim 100$ pc of this AGN as $\alpha_{\rm CO} = 4.1$ and$\alpha_{\rm CI} = 4.4~M_\odot$ (K km s$^{-1}$ pc$^2$)$^{-1}$, respectively.Our results suggest that the CI enhancement is potentially a good marker ofAGNs that could be used in a new submillimeter diagnostic method toward dustyenvironments.

We present a new constraint on the mass of the black hole in the active S0 galaxy NGC 5273. Due to the proximity of the galaxy at 16.6 ± 2.1 Mpc, we were able to resolve and extract the bulk motions of stars near the central black hole using adaptive-optics-assisted observations with the Gemini Near-infrared Integral Field Spectrograph, as well as constrain the large-scale kinematics using archival Spectroscopic Areal Unit for Research and Optical Nebulae spectroscopy. High-resolution Hubble Space Telescope imaging allowed us to generate a surface-brightness decomposition, determine approximate mass-to-light ratios for the bulge and disk, and obtain an estimate for the disk inclination. We constructed an extensive library of dynamical models using the Schwarzschild orbit-superposition code FORSTAND, exploring a range of disk and bulge shapes, halo masses, etc. We determined a black hole mass of M • = [0.5–2] × 107 M ⊙, where the low side of the range is in agreement with the reverberation mapping measurement of M • = [4.7 ± 1.6] × 106 M ⊙. NGC 5273 is one of the few nearby galaxies that hosts a broad-lined active galactic nucleus, allowing a crucial comparison of black hole masses derived from independent mass-measurement techniques. [ABSTRACT FROM AUTHOR]

We analyze a sample of 25 [Ne v ] (λ 3426) emission-line galaxies at 1.4 < z < 2.3 using Hubble Space Telescope/Wide Field Camera 3 G102 and G141 grism observations from the CANDELS Ly α Emission at Reionization (CLEAR) survey. [Ne v ] emission probes extremely energetic photoionization (creation potential of 97.11 eV) and is often attributed to energetic radiation from active galactic nuclei (AGNs), shocks from supernovae, or an otherwise very hard ionizing spectrum from the stellar continuum. In this work, we use [Ne v ] in conjunction with other rest-frame UV/optical emission lines ([O ii ] λ λ 3726, 3729, [Ne iii ] λ 3869, H β, [O iii ] λ λ 4959, 5007, H α +[N ii ] λ λ 6548, 6583, [S ii ] λ λ 6716, 6731), deep (2–7 Ms) X-ray observations (from Chandra), and mid-infrared imaging (from Spitzer) to study the origin of this emission and to place constraints on the nature of the ionizing engine. The majority of the [Ne v ]-detected galaxies have properties consistent with ionization from AGNs. However, for our [Ne v ]-selected sample, the X-ray luminosities are consistent with local (z ≲ 0.1) X-ray-selected Seyferts, but the [Ne v ] luminosities are more consistent with those from z ∼ 1 X-ray-selected QSOs. The excess [Ne v ] emission requires either reduced hard X-rays or a ∼0.1 keV excess. We discuss possible origins of the apparent [Ne v ] excess, which could be related to the "soft (X-ray) excess" observed in some QSOs and Seyferts and/or be a consequence of a complex/anisotropic geometry for the narrow-line region, combined with absorption from a warm, relativistic wind ejected from the accretion disk. We also consider implications for future studies of extreme high-ionization systems in the epoch of reionization (z ≳ 6) with the James Webb Space Telescope. [ABSTRACT FROM AUTHOR]

We investigate the stellar mass–black hole mass (  * –  BH ) relation with type 1 active galactic nuclei (AGNs) down to  BH = 10 7 M ⊙ , corresponding to a ≃ −21 absolute magnitude in rest-frame ultraviolet, at z = 2–2.5. Exploiting the deep and large-area spectroscopic survey of the Hobby–Eberly Telescope Dark Energy Experiment (HETDEX), we identify 66 type 1 AGNs with  BH ranging from 107–1010 M ⊙ that are measured with single-epoch virial method using C iv emission lines detected in the HETDEX spectra.  * of the host galaxies are estimated from optical to near-infrared photometric data taken with Spitzer, the Wide-field Infrared Survey Explorer, and ground-based 4–8 m class telescopes by CIGALE spectral energy distribution (SED) fitting. We further assess the validity of SED fitting in two cases by host-nuclear decomposition performed through surface brightness profile fitting on spatially resolved host galaxies with the James Webb Space Telescope/NIRCam CEERS data. We obtain the  * –  BH relation covering the unexplored low-mass ranges of  BH ∼ 10 7 – 10 8 M ⊙ , and conduct forward modeling to fully account for the selection biases and observational uncertainties. The intrinsic  * –  BH relation at z ∼ 2 has a moderate positive offset of 0.52 ± 0.14 dex from the local relation, suggestive of more efficient black hole growth at higher redshift even in the low-mass regime of  BH ∼ 10 7 – 10 8 M ⊙ . Our  * –  BH relation is inconsistent with the  BH suppression at the low-  * regime predicted by recent hydrodynamic simulations at a 98% confidence level, suggesting that feedback in the low-mass systems may be weaker than those produced in hydrodynamic simulations. [ABSTRACT FROM AUTHOR]

In the third paper from the COOL–LAMPS Collaboration, we report the discovery of COOL J0542-2125, a gravitationally lensed quasar at z = 1.84, observed as three images due to an intervening massive galaxy cluster at z = 0.61. The lensed quasar images were identified in a search for lens systems in recent public optical imaging data and have separations on the sky up to 25.″9, wider than any previously known lensed quasar. The galaxy cluster acting as a strong lens appears to be in the process of merging, with two subclusters separated by ∼1 Mpc in the plane of the sky, and their central galaxies showing a radial velocity difference of ∼1000 km s−1. Both cluster cores show strongly lensed images of an assortment of background sources, as does the region between them. A preliminary strong lens model implies masses of M < 250 k p c = 1.79 − 0.01 + 0.16 × 10 14 M ⊙ and M < 250 k p c = 1.48 − 0.10 + 0.04 × 10 14 M ⊙ for the east and west subclusters, respectively. This line of sight is also coincident with an ROSAT ALL-sky Survey source, centered between the two confirmed cluster halos reminiscent of other major cluster-scale mergers. Archival and new follow-up imaging show flux variability in the quasar images of up to 0.4 mag within ∼1 yr, and new multicolor imaging data reveal a 2 σ detection of the underlying quasar host. A lens system with this configuration offers rare opportunities for a range of future studies of both the lensed quasar and its host and the foreground cluster merger causing the lensing. [ABSTRACT FROM AUTHOR]

Fast accreting, extremely luminous quasars contribute heavily to the feedback process within galaxies. While these systems are most common at cosmic noon ( z ∼ 2), here we choose to study PDS 456, an extremely luminous ( L _bol ∼ 10 ^47 erg s ^−1 ) but nearby ( z ∼ 0.185) quasar where the physics of feedback can be studied in greater detail. We present the results from our analysis of the JWST MIRI/Medium Resolution Spectroscopy (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 ], and [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 polycyclic aromatic hydrocarbon 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.

We investigate the kinematics and dynamics of the molecular and ionized gas in the host galaxies of three Palomar-Green quasars at low redshifts, benefiting from the archival millimeter-wave interferometric and optical integral field unit data. We study the kinematics of both cold molecular and hot ionized gas by analyzing the CO and H α data cubes, and construct the mass distributions of our sample through gas dynamics, utilizing a priori knowledge regarding the galaxy light distribution. We find no systematic offset between the stellar mass derived from our dynamical method and that from the broadband photometry and mass-to-light ratio, suggesting the consistency of both methods. We then study the kinetic pressure and the weight of the interstellar medium (ISM) using our dynamical mass model. By studying the relationship between kinetic pressure and gravitational pressure of the quasar host galaxies, we find an equivalence in the hydrostatic equilibrium states of ISM in the quasar host galaxies, similar to the result of gas equilibrium in normal star-forming galaxies, suggesting minimal quasar feedback. Regarding noncircular motion as indicative of quasar-driven outflows, we observe an exceptionally low coupling efficiency between molecular gas outflow and active galactic nucleus bolometric luminosities. These results demonstrate the marginal influence of the central engine on the properties of cold molecular gas in quasar host galaxies.

The James Webb Space Telescope opens a new window to directly probe luminous quasars powered by billion solar mass black holes in the Epoch of Reionization and their coevolution with massive galaxies with unprecedented details. In this paper, we report the first results from a deep NIRSpec integral field unit spectroscopic study of a quasar at z = 7.5. We obtain a bolometric luminosity of ∼1.8 × 10 ^47 erg s ^−1 and a black hole mass of ∼0.7–2.5 × 10 ^9 M _⊙ based on the H β emission line in the quasar spectrum. We discover ∼2 kpc scale, highly blueshifted (∼−870 km s ^−1 ) and broad (∼1400 km s ^−1 ) [O iii ] line emission after the quasar point-spread function has been subtracted. Such line emission most likely originates from a fast, quasar-driven outflow, the earliest one at galactic scales known so far. The dynamical properties of this outflow fall within the typical ranges of quasar-driven outflows at lower redshift, and the outflow may be fast enough to reach the circumgalactic medium. Combining both the extended and nuclear outflow together, the mass outflow rate, ∼300 M _⊙ yr ^−1 , is ∼60%–380% of the star formation rate of the quasar host galaxy, suggesting that the outflow may expel a significant amount of gas from the inner region of the galaxy. The kinetic energy outflow rate, ∼3.6 × 10 ^44 erg s ^−1 , is ∼0.2% of the quasar bolometric luminosity, which is comparable to the minimum value required for negative feedback based on simulation predictions. The dynamical timescale of the extended outflow is ∼1.7 Myr, consistent with the typical quasar lifetime in this era.

We present Gemini near-infrared integral field spectrograph K -band observations of the central 400 pc of NGC 1266, a nearby ( D ≈ 30 Mpc) post-starburst galaxy with a powerful multiphase outflow and a shocked interstellar medium. We detect seven H _2 rovibrational emission lines excited thermally to T ∼ 2000 K, and weak Br γ emission, consistent with a fast continuous shock (or C-shock). With these bright H _2 lines, we observe the spatial structure of the shock with an unambiguous tracer for the first time. The Br γ emission is concentrated in the central ≲100 pc, indicating that any remaining star formation in NGC 1266 is in the nucleus, while the surrounding cold molecular gas has little ongoing star formation. Though it is unclear what fraction of this Br γ emission is from star formation or the active galactic nuclei (AGN), assuming it is entirely due to star formation we measure an instantaneous star formation rate of 0.7 M _⊙ yr ^−1 , though the star formation rate may be significantly higher in the presence of additional extinction. NGC 1266 provides a unique laboratory to study the complex interactions between AGN, outflows, shocks, and star formation, all of which are necessary to unravel the evolution of the post-starburst phase.

Outflowing gas from supermassive black holes in the centers of active galaxies has been postulated as a major contributor to galactic evolution. To explore the interaction between narrow-line region (NLR) outflows and their host galaxies, we use Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) spectra and Wide Field Camera 3 (WFC3) images of 15 nearby ( z < 0.02) active galactic nuclei (AGN) to determine the extents and geometries of their NLRs. We combine new HST WFC3 continuum and [O iii ] λ 5007 images of 11 AGN with four archival AGN to match existing spectra from HST STIS. For the six AGN with suitable long-slit coverage of their NLRs, we use isophotal fitting of ground-based images, continuum-subtracted [O iii ] images, and the STIS spectra, to resolve, measure, and de-project the gas kinematics to the plane of the host galaxy disk and distinguish NLR outflows from galaxy rotation and/or kinematically disturbed gas. We find an average [O iii ] extent of ∼680 pc with a correlation between gas extent and [O iii ] luminosity of R _[O III] ∝ ${L}_{[{\rm{O}}\,\mathrm{III}]}^{0.39}$ . The measured extents depend strongly on the depth of the [O iii ] images, highlighting the importance of adopting uniform thresholds when analyzing scaling relationships. The outflows reach from 39% to 88% of the full NLR extents, and we find that all six of the AGN with STIS coverage of their entire NLRs show strong kinematic evidence for outflows, despite previous uncertainty for these AGN. This suggests that NLR outflows are ubiquitous in moderate-luminosity AGN and that standard criteria for kinematic modeling are essential for identifying outflows.

We present a comprehensive X-ray analysis and spectral energy distribution (SED) fitting of WISEA J171419.96+602724.6, an extremely luminous type 2 quasar at z = 2.99. The source was suggested as a candidate Compton-thick (column density N _H > 1.5×10 ^24 cm ^−2 ) quasar by a short XMM-Newton observation in 2011. We recently observed the source with deep NuSTAR and XMM-Newton exposures in 2021 and found that the source has a lower obscuration of N _H ∼ 5×10 ^22 cm ^−2 with an about four times lower flux. The two epochs of observations suggested that the source was significantly variable in X-ray obscuration, flux, and intrinsic luminosity at 2 σ –3 σ in less than 2.5 yr (in the source rest frame). We performed SED fitting of this source using Code Investigating GALaxy Emission thanks to its great availability of multiwavelength data (from hard X-rays to radio). The source is very luminous, with a bolometric luminosity of L _BOL ∼ 2.5 × 10 ^47 erg s ^−1 . Its host galaxy has a huge star formation rate (SFR) of ∼1280 M _☉ yr ^−1 and a huge stellar mass of ∼1.1 × 10 ^12 M _☉ . The correlation between the SFR and stellar mass of this source is consistent with what was measured in the high- z quasars. It is also consistent with what was measured in the main-sequence star-forming galaxies, suggesting that the presence of the active nucleus in our target does not enhance or suppress the SFR of its host galaxy. The source is an infrared hyperluminous, obscured galaxy with a significant amount of hot dust in its torus and shares many similar properties with hot, dust-obscured galaxies.

We present near-infrared (NIR) spectroscopy using the MMT and Magellan infrared spectrograph for a sample of 29 massive galaxies ( $\mathrm{log}\ {M}_{* }/{M}_{\odot }\gtrsim 10$ ) at z ∼ 0.7 with optical spectroscopy from the Large Early Galaxy Astrophysics Census (LEGA-C) survey. Having both optical and NIR spectroscopy at this redshift allows us to measure the full suite of rest-optical strong emission lines, enabling the study of ionization sources and the rest-optical selection of active galactic nuclei (AGN), as well as the measurement of dust-corrected H α -based star formation rates (SFRs). We find that 11 out of 29 galaxies host AGN. We infer the nonparametric star formation histories with the spectral energy distribution fitting code Prospector and classify galaxies as star-forming, green valley, or quiescent based on their most recent specific SFRs. We explore the connection between AGN activity and suppressed star formation, and find that 89% ± 15% of galaxies in the green valley or below host AGN, while only 15% ± 8% of galaxies above the green valley host AGN. We construct the star-forming main sequence (SFMS) and find that the AGN host galaxies are 0.37 dex below the SFMS, while galaxies without detectable AGN are consistent with being on the SFMS. However, when compared to a bootstrapped mass-matched sample, the SFRs of our sample of AGN host galaxies are consistent with the full LEGA-C sample. Based on this mass-matched analysis, we cannot rule out that this suppression of star formation is driven by other processes associated with the higher mass of the AGN sample. We therefore cannot link the presence of AGN activity to the quenching of star formation.

Radio spectral shape of quasars can provide insight into the ages of quasars. We have compiled data for 1804 quasars with z ≲ 1 from the Sloan Digital Sky Survey (SDSS). Additionally, these quasars were also mapped by the Low-Frequency Array at 144 MHz and the Very Large Array Sky Survey at 3000 MHz. The radio spectral index, designated as ${\alpha }_{3000}^{144}$ (with S ( ν ) ∝ ν ^α ), is analyzed between 144 and 3000 MHz as a proxy for the ages of quasars. We measure the [O III ] λ 5007 emission line in the SDSS spectra. A strong correlation was found between the equivalent width of the core component of the [O III ] λ 5007 emission line and ${\alpha }_{3000}^{144}$ . This relationship suggests that the core component of the [O III ] λ 5007 emission line could potentially serve as a surrogate for the evolutionary stage of a quasar. The quasars at an early stage of evolutions tend to show weaker [O III ] λ 5007 emission, while older quasars exhibit stronger [O III ] λ 5007 emission.

We introduce an improved method for decomposing the emission of active galactic nuclei (AGN) and their host galaxies using templates from principal component analysis (PCA). This approach integrates prior information from PCA with a penalized pixel fitting mechanism that improves the precision and effectiveness of the decomposition process. Specifically, we have reduced the degeneracy and overfitting in AGN host decomposition, particularly for those with low signal-to-noise ratios (SNRs), where traditional methods tend to fail. By applying our method to 76,565 Sloan Digital Sky Survey Data Release 16 quasars with z < 0.8, we achieve a success rate of ≈94%, thus establishing the largest host-decomposed spectral catalog of quasars to date. Our fitting results consider the impact of the host galaxy on the overestimation of the AGN luminosity and black hole mass ( M _BH ). Furthermore, we obtained stellar velocity dispersion ( σ _⋆ ) measurements for 4137 quasars. The slope of the M _BH − σ _⋆ relation in this subsample is generally consistent with previous quasar studies beyond the local Universe. Our method provides a robust and efficient approach to disentangle the AGN and host galaxy components across a wide range of SNRs and redshifts.

We present a multifrequency polarimetric study for the quasar 1604+159. The source was observed at the L band with the American Very Long Baseline Array and the L , X , and U bands with the Very Large Array. These observations provide different resolutions from mas to arcsec, enabling us to probe the morphology and magnetic field from tens of parsec to hundreds of kiloparsec scale. We detect a symmetrical Fanaroff–Riley Class I–like structure. The source has several lobes and bulges, forming a cocoon shape. The polarization is normal to the edges of the structure with high fractional polarization up to ∼60%. Two hotspots are observed at the eastern and western sides of the source, located symmetrically relative to the core. The flux density ratio (>1.5) between the two hotspots suggests the Doppler beaming effect exists at a large scale. The polarized emission in the hotspots also shows a symmetrical structure with an oblique direction from the jet direction. In general, the jet propagates in a collimating structure with several bends. Polarization is also detected perpendicular to the local jet from ∼100 mas to ∼1″. The jet shows strong polarized intensity and high fractional polarization at the bending edges. We discuss the possible origins of the observed structure and magnetic field.

We present a sample of 1165 extreme emission-line galaxies (EELGs) at 4 < z < 9 selected using James Webb Space Telescope (JWST) NIRCam photometry in the Cosmic Evolution Early Release Science (CEERS) program. We use a simple method to photometrically identify EELGs with H β + [O iii ] (combined) or H α emission of observed-frame equivalent width (EW) > 5000 Å. JWST/NIRSpec spectroscopic observations of a subset (34) of the photometrically selected EELGs validate our selection method: All spectroscopically observed EELGs confirm our photometric identification of extreme emission, including some cases where the spectral-energy-distribution-derived photometric redshifts are incorrect. We find that the medium-band F410M filter in CEERS is particularly efficient at identifying EELGs, both in terms of including emission lines in the filter and in correctly identifying the continuum between H β + [O iii ] and H α in the neighboring broadband filters. We present examples of EELGs that could be incorrectly classified as ultrahigh redshift ( z > 12) as a result of extreme H β + [O iii ] emission blended across the reddest photometric filters. We compare the EELGs to the broader (subextreme) galaxy population in the same redshift range and find that they are consistent with being the bluer, high-EW tail of a broader population of emission-line galaxies. The highest-EW EELGs tend to have more compact emission-line sizes than continuum sizes, suggesting that active galactic nuclei are responsible for at least some of the most extreme EELGs. The photometrically inferred emission-line ratios are consistent with interstellar medium conditions with high ionization and moderately low metallicity, consistent with previous spectroscopic studies.

We present the discovery of a luminous X-ray active galactic nucleus (AGN) in the dwarf galaxy merger RGG 66. The black hole is predicted to have a mass of M _BH ∼ 10 ^5.4 M _⊙ and to be radiating close to its Eddington limit ( L _bol / L _Edd ∼ 0.75). The AGN in RGG 66 is notable both for its presence in a late-stage dwarf–dwarf merger and for its luminosity of L _2–10 keV = 10 ^42.2 erg s ^−1 , which is among the most powerful AGNs known in nearby dwarf galaxies. The X-ray spectrum has a best-fit photon index of Γ = 2.4 and an intrinsic absorption of N _H ∼ 10 ^21 cm ^−2 . These results come from a follow-up Chandra X-ray Observatory study of four irregular/disturbed dwarf galaxies with evidence for hosting AGNs based on optical spectroscopy. The remaining three dwarf galaxies do not have detectable X-ray sources with upper limits of L _2–10 keV ≲ 10 ^40 erg s ^−1 . Taken at face value, our results on RGG 66 suggest that mergers may trigger the most luminous of AGNs in the dwarf galaxy regime, just as they are suspected to do in more massive galaxy mergers.

Active galactic nuclei (AGN) feedback and its impact on their host galaxies are critical to our understanding of galaxy evolution. Here, we present a combined analysis of new high resolution ultraviolet (UV) data from the Ultraviolet Imaging Telescope (UVIT) on AstroSat and archival optical spectroscopic data from the Very Large Telescope/MUSE, for the Seyfert galaxy, NGC 1365. Concentrating on the central 5 kpc region, the UVIT images in the far- and near-UV show bright star-forming knots in the circumnuclear ring as well as a faint central source. After correcting for extinction, we found the star formation rate (SFR) surface density of the circumnuclear 2 kpc ring to be similar to other starbursts, despite the presence of an AGN outflow, as seen in [O iii ] 5007 Å. On the other hand, we found fainter UV and thus lower SFR in the direction southeast of the AGN relative to northwest in agreement with observations at other wavelengths from JWST and Atacama Large Millimeter/submillimeter Array. The AGN outflow velocity is found to be lesser than the escape velocity, suggesting that the outflowing gas will rain back into the galaxy. The deep UV data have also revealed diffuse UV emission in the direction of the AGN outflow. By combining [O iii ] and UV data, we found the diffuse emission to be of AGN origin.

Feedback from supermassive black holes is believed to be a critical driver of the observed color bimodality of galaxies above the Milky Way mass scale. Active galactic nuclei (AGN) feedback has been modeled in many galaxy formation simulations, but most implementations have involved simplified prescriptions or a coarse-grained interstellar medium (ISM). We present the first set of Feedback In Realistic Environments (FIRE)-3 cosmological zoom-in simulations with AGN feedback evolved to z ∼ 0, examining the impact of AGN feedback on a set of galaxies with halos in the mass range 10 ^12 –10 ^13 M _⊙ . These simulations combine detailed stellar and ISM physics with multichannel AGN feedback including radiative feedback, mechanical outflows, and, in some simulations, cosmic rays (CRs). We find that massive (> L *) galaxies in these simulations can match local scaling relations including the stellar mass–halo mass relation and the M _BH – σ relation; in the stronger model with CRs, they also match the size–mass relation and the Faber–Jackson relation. Many of the massive galaxies in the simulations with AGN feedback have quenched star formation and elliptical morphologies, in qualitative agreement with observations. In contrast, simulations at the massive end without AGN feedback produce galaxies that are too massive and form stars too rapidly, are order-of-magnitude too compact, and have velocity dispersions well above Faber–Jackson. Despite these successes, the AGN models analyzed do not produce uniformly realistic galaxies when the feedback parameters are held constant: While the stronger model produces the most realistic massive galaxies, it tends to overquench the lower-mass galaxies. This indicates that further refinements of the AGN modeling are needed.

We study magnetic field strengths along the jet in NGC 315. First, we estimated the angular velocity of rotation in the jet magnetosphere by comparing the measured velocity profile of NGC 315 with the magnetohydrodynamic jet model proposed by Tomimatsu and Takahashi. Similar to the case of M87, we find that the model can reproduce the logarithmic feature of the velocity profile and suggest a slowly rotating black hole magnetosphere for NGC 315. By substituting the estimated Ω _F into the jet power predicted by the Blandford–Znajek mechanism, we estimate the magnetic field strength near the event horizon of the central black hole as 5 × 10 ^3 G ≲ B _H ≲ 2 × 10 ^4 G. We then estimate magnetic field strengths along the jet by comparing the spectral index distribution obtained from very long baseline interferometry (VLBI) observations with a synchrotron-emitting jet model. Then we constrain the magnetic field strength at a deprojected distance z from the black hole to be in the range 0.06 G ≲ B ( z ) ≲ 0.9 G for 5.2 × 10 ^3 r _g ≲ z ≲ 4.9 × 10 ^4 r _g , where r _g represents the gravitational radius. By combining the obtained field strengths at the event horizon and the downstream section of the jet, we find that the accretion flow at the jet base is consistent with a magnetically arrested disk. We discuss a comparison of the jet power and the magnetic flux anchored to the event horizon in NGC 315 and M87.

Neutral atomic hydrogen and molecular gas in the host galaxies of radio active galactic nuclei can be traced using H i 21 cm and OH-1667 MHz absorption lines to understand the fueling and feedback processes. We present the results of an H i and OH absorption survey with the Five-hundred-meter Aperture Spherical radio Telescope toward 40 radio sources of low–intermediate radio luminosity (∼10 ^23 –10 ^26 W Hz ^−1 at 1.4 GHz), red mid-infrared color (W2[4.6 μ m]–W3[12 μ m] > 2.5 mag), and redshift up to 0.35. From 13 sources with good data at H i observing frequencies, we report the detection of H i absorption toward eight sources, five of which are new detections, including four in the redshift range 0.25–0.35. Our detection rates are consistent with our previous results, with the dependence on the star formation history of the host galaxies reflected in the mid-infrared Wide-field Infrared Survey Explorer W2−W3 colors and the compactness of the radio sources. We find no significant dependence of the detection rates on radio luminosity or redshift. We also find that the H i column densities are anticorrelated with the low-frequency spectral indices ( ${\alpha }_{150\ \mathrm{MHz}}^{1.4\ \mathrm{GHz}}$ , S _ν ∝ ν ^− ^α ). We do not have any detections from 23 sources with good data at OH observing frequencies. However, by stacking the spectra, we estimate the 3 σ upper limit of the OH column density to be 2.27 × 10 ^14 T _ex /10 K × 1/ f _c cm ^−2 . By stacking the OH spectra for seven associated H i absorbers, we get a 3 σ upper limit of 3.47 × 10 ^14 T _ex /10 K × 1/ f _c cm ^−2 on the OH column density and 1.78 × 10 ^−7 on the [OH]/[H i ] ratio.

Circumnuclear star formation (SF) is generally seen in galaxies hosting active galactic nuclei (AGN); however, the connection between the AGN activity and SF in them is less well understood. To explore this connection on scales of a few tens of parsecs to a few tens of kiloparsecs and larger, we carried out an investigation of SF in seven Seyfert-type AGN and one low-ionization nuclear emission-line region galaxy, using observations with the Ultraviolet Imaging Telescope on board AstroSat in the near-ultraviolet (2000–3000 Å) and far-ultraviolet (1300−1800 Å) bands. A total of 1742 star-forming regions were identified, having size scales of 0.010–63.642 kpc ^2 . Considering all the galaxies, we found a positive correlation between their total surface density of SF (Σ _SFR ) and extinction. For five galaxies, namely NGC 1365, NGC 4051, NGC 4321, NGC 5033, and NGC 6814, we found a gradual decrease of both extinction and Σ _SFR from the centre to the outer regions. Four sources are found to lie in the main sequence of star-forming galaxies, and the other four lie away from it. We found the ratio of the star formation rate (SFR) in the nuclear region to the total SFR to be positively correlated with the Eddington ratio. This points to the influence of AGN in enhancing the SF characteristics of the hosts. However, the impact is dominant only in the central nuclear region and has no significant effect on the larger scales probed in this work.