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We present a study of molecular gas, traced via CO (3–2) from Atacama Large Millimeter/submillimeter Array data, of four z < 0.2, 'radio quiet', type 2 quasars (Lbol ∼ 1045.3–1046.2 erg s−1; L |$_{\mathrm{1.4\, GHz}}\sim 10^{23.7}\!-\!10^{24.3}$|   W  Hz−1). Targets were selected to have extended radio lobes (≥ 10 kpc), and compact, moderate-power jets (1–10 kpc; P jet ∼ 1043.2–1043.7 erg s−1). All targets show evidence of central molecular outflows, or injected turbulence, within the gas discs (traced via high-velocity wing components in CO emission-line profiles). The inferred velocities (V out = 250–440 km s−1) and spatial scales (0.6–1.6 kpc), are consistent with those of other samples of luminous low-redshift active galactic nuclei. In two targets, we observe extended molecular gas structures beyond the central discs, containing 9–53  per cent of the total molecular gas mass. These structures tend to be elongated, extending from the core, and wrap-around (or along) the radio lobes. Their properties are similar to the molecular gas filaments observed around radio lobes of, mostly 'radio loud', brightest cluster galaxies. They have the following: projected distances of 5–13 kpc; bulk velocities of 100–340 km s−1; velocity dispersion of 30–130 km s−1; inferred mass outflow rates of 4–20 M⊙ yr−1; and estimated kinetic powers of 1040.3–1041.7 erg s−1. Our observations are consistent with simulations that suggest moderate-power jets can have a direct (but modest) impact on molecular gas on small scales, through direct jet–cloud interactions. Then, on larger scales, jet-cocoons can push gas aside. Both processes could contribute to the long-term regulation of star formation. [ABSTRACT FROM AUTHOR]

Cosmological simulations fail to reproduce realistic galaxy populations without energy injection from active galactic nuclei (AGN) into the interstellar medium (ISM) and circumgalactic medium (CGM); a process called 'AGN feedback'. Consequently, observational work searches for evidence that luminous AGN impact their host galaxies. Here, we review some of this work. Multi-phase AGN outflows are common, some with potential for significant impact. Additionally, multiple feedback channels can be observed simultaneously; e.g., radio jets from 'radio quiet' quasars can inject turbulence on ISM scales, and displace CGM-scale molecular gas. However, caution must be taken comparing outflows to simulations (e.g., kinetic coupling efficiencies) to infer feedback potential, due to a lack of comparable predictions. Furthermore, some work claims limited evidence for feedback because AGN live in gas-rich, star-forming galaxies. However, simulations do not predict instantaneous, global impact on molecular gas or star formation. The impact is expected to be cumulative, over multiple episodes. [ABSTRACT FROM AUTHOR]

Negative feedback from active galactic nuclei (AGN) is the leading mechanism for the quenching of massive galaxies in the vast majority of modern galaxy evolution models. However, direct observational evidence that AGN feedback causes quenching on a population scale is lacking. Studies have shown that luminous AGN are preferentially located in gas-rich and star-forming galaxies, an observation that has sometimes been suggested to be in tension with a negative AGN feedback picture. We investigate three of the current cosmological simulations (i llustrisTNG, EAGLE, and SIMBA) along with post-processed models for molecular hydrogen gas masses and perform similar tests to those used by observers. We find that the simulations predict: (i) no strong negative trends between L bol and |$f_{\mathrm{ H}_2}$| or specific star formation rate (sSFR); (ii) both high-luminosity (⁠|$L_{\rm {bol}} \ge 10^{44}\rm {\, erg\, s^{-1}}$|⁠) and high Eddington ratio (λEdd  |$\ge 1{{\ \rm per\ cent}}$|⁠) AGN are preferentially located in galaxies with high molecular gas fractions and sSFR; and (iii) that the gas-depleted and quenched fractions of AGN host galaxies are lower than a control sample of non-active galaxies. These three findings are in qualitative agreement with observational samples at z = 0 and z = 2 and show that such results are not in tension with the presence of strong AGN feedback, which all simulations we employ require to produce realistic massive galaxies. However, we also find quantifiable differences between predictions from the simulations, which could allow us to observationally test the different subgrid feedback models. [ABSTRACT FROM AUTHOR]

We present high-resolution (∼2.4 kpc) ALMA band 7 observations (rest-frame λ ∼ 250  |$\mu$| m) of three powerful z  ∼ 2.5 quasars (L bol = 1047.3–1047.5 erg s−1). These targets have previously been reported as showing evidence for suppressed star formation based on cavities in the narrow H α emission at the location of outflows traced with [O  iii ] emission. Here, we combine the ALMA observations with a re-analysis of the VLT/SINFONI data to map the rest-frame far-infrared emission, H α emission, and [O  iii ] emission. In all targets, we observe high velocity [O  iii ] gas (i.e. W80 ∼ 1000–2000 km s−1) across the whole galaxy. We do not identify any H α emission that is free from contamination from AGN-related processes; however, based on SED analyses, we show that the ALMA data contain a significant dust-obscured star formation component in two out of the three systems. This dust emission is found to be extended over ≈1.5–5.5 kpc in the nuclear regions, overlaps with the previously reported H α cavities and is co-spatial with the peak in surface brightness of the [O  iii ] outflows. In summary, within the resolution and sensitivity limits of the data, we do not see any evidence for a instantaneous shut down of in situ star formation caused directly by the outflows. However, similar to the conclusions of previous studies and based on our measured star formation rates, we do not rule out that the global host galaxy star formation could be suppressed on longer time-scales by the cumulative effect of quasar episodes during the growth of these massive black holes. [ABSTRACT FROM AUTHOR]

Aims. The SINFONI survey for Unveiling the Physics and Effect of Radiative feedback (SUPER) aims to trace and characterise ionised gas outflows and their impact on star formation in a statistical sample of X-ray selected active galactic nuclei (AGN) at z ∼ 2. We present the first SINFONI results for a sample of 21 Type 1 AGN spanning a wide range in bolometric luminosity (log Lbol = 45.4–47.9 erg s−1). The main aims of this paper are to determine the extension of the ionised gas, characterise the occurrence of AGN-driven outflows, and link the properties of such outflows with those of the AGN. Methods. We used adaptive optics-assisted SINFONI observations to trace ionised gas in the extended narrow line region using the [O III] λ5007 line. We classified a target as hosting an outflow if its non-parametric velocity of the [O III] line, w80, was larger than 600 km s−1. We studied the presence of extended emission using dedicated point-spread function (PSF) observations, after modelling the PSF from the Balmer lines originating from the broad line region. Results. We detect outflows in all the Type 1 AGN sample based on the w80 value from the integrated spectrum, which is in the range ∼650–2700 km s−1. There is a clear positive correlation between w80 and the AGN bolometric luminosity (> 99% correlation probability), and the black hole mass (98% correlation probability). A comparison of the PSF and the [O III] radial profile shows that the [O III] emission is spatially resolved for ∼35% of the Type 1 sample and the outflows show an extension up to ∼6 kpc. The relation between maximum velocity and the bolometric luminosity is consistent with model predictions for shocks from an AGN-driven outflow. The escape fraction of the outflowing gas increases with the AGN luminosity, although for most galaxies, this fraction is less than 10%. [ABSTRACT FROM AUTHOR]

Studies investigating the relationship between active galactic nucleus (AGN) power and the star formation rates (SFRs) of their host galaxies often rely on averaging techniques – such as stacking – to incorporate information from non-detections. However, averages, and especially means, can be strongly affected by outliers and can therefore give a misleading indication of the 'typical' case. Recently, a number of studies have taken a step further by binning their sample in terms of AGN power (approximated by the 2–10 keV luminosity of the AGN), and investigating how the SFR distribution differs between these bins. These bin thresholds are often weakly motivated, and binning implicitly assumes that sources within the same bin have similar (or even identical) properties. In this paper, we investigate whether the distribution of host SFRs – relative to the locus of the star-forming main sequence (i.e. R MS) – changes continuously as a function of AGN power. We achieve this by using a hierarchical Bayesian model that completely removes the need to bin in AGN power. In doing so, we find strong evidence that the R MS distribution changes with 2–10 keV X-ray luminosity. The results suggest that higher X-ray luminosity AGNs have a tighter physical connection to the star-forming process than lower X-ray luminosity AGNs, at least within the 0.8 < z < 1.2 redshift range considered here. [ABSTRACT FROM AUTHOR]

As part of our KMOS AGN Survey at High-redshift (KASHz), we present spatially resolved VLT/KMOS and VLT/SINFONI spectroscopic data and ALMA 870  μ m continuum imaging of eight z  = 1.4–2.6 moderate AGN (⁠|$L_{\rm 2-10 \, \rm kev}$|  = 1042–1045 ergs s−1). We map [O  iii ], H α and rest-frame FIR emission to search for any spatial anticorrelation between ionised outflows (traced by the [O  iii ] line) and star formation (SF; traced by H α and FIR), that has previously been claimed for some high-z AGN and used as evidence for negative and/or positive AGN feedback. First, we conclude that H α is unreliable to map SF inside our AGN host galaxies based on: (i) SF rates inferred from attenuation-corrected H α can lie below those inferred from FIR; (ii) the FIR continuum is more compact than the H α emission by a factor of ∼2 on average; (iii) in half of our sample, we observe significant spatial offsets between the FIR and H α emission, with an average offset of 1.4 ± 0.6 kpc. Secondly, for the five targets with outflows we find no evidence for a spatial anticorrelation between outflows and SF using either H α or FIR as a tracer. This holds for our re-analysis of a famous z  = 1.6 X-ray AGN ('XID 2028') where positive and negative feedback has been previously claimed. Based on our results, any impact on SF by ionised outflows must be subtle, either occurring on scales below our resolution, or on long time-scales. [ABSTRACT FROM AUTHOR]

By using data from the Atacama Large Millimeter/submillimeter Array and near-infrared (NIR) integral field spectrographs, including both Spectrograph for INtegral Field Observations in the Near Infrared and K-band Multi Object Spectrograph on the Very Large Telescope, we investigate the two-dimensional distributions of H and rest-frame far-infrared (FIR) continuum in six submillimeter galaxies (SMGs) at z ~ 2. At a similar spatial resolution (~0: 005 FWHM; ~4.5 kpc at z = 2), we find that the half-light radius of Hα is significantly larger than that of the FIR continuum in half of the sample, and on average Hα is a median factor of 2:0 ± 0:4 larger. Having explored various ways to correct for the attenuation, we find that the attenuation-corrected Hα-based star-formation rates (SFRs) are systematically lower than the infrared (IR)-based SFRs by at least a median factor of 3 ± 1, which cannot be explained by the diαerence in half-light radius alone. In addition, we find that in 40% of cases the total V-band attenuation (AV) derived from energy balance modeling of the full ultraviolet (UV)-to-FIR spectral energy distributions (SEDs) is significantly higher than what is derived from SED modeling using only the UV-to-NIR part of the SEDs, and the discrepancy appears to increase with increasing total infrared luminosity. Finally, in considering all of our findings along with the studies in the literature, we postulate that the dust distributions in SMGs, and possibly also in less IR luminous z ~ 2 massive star-forming galaxies, can be decomposed into the following three main components: the diαuse dust heated by older stellar populations, the more obscured and extended young star-forming Hii regions, and the heavily obscured central regions that have a low filling factor but dominate the infrared luminosity in which the majority of attenuation cannot be probed via UV-to-NIR emissions. [ABSTRACT FROM AUTHOR]

We present an analysis of the gas dynamics of star-forming galaxies at z ∼ 1.5 using data from the KMOS Galaxy Evolution Survey. We quantify the morphology of the galaxies using HST candels imaging parametrically and non-parametrically. We combine the H α dynamics from KMOS with the high-resolution imaging to derive the relation between stellar mass (M *) and stellar specific angular momentum (j *). We show that high-redshift star-forming galaxies at z ∼ 1.5 follow a power-law trend in specific stellar angular momentum with stellar mass similar to that of local late-type galaxies of the form j *  ∝   M |$_*^{0.53\, \pm \, 0.10}$|⁠. The highest specific angular momentum galaxies are mostly disc-like, although generally both peculiar morphologies and disc-like systems are found across the sequence of specific angular momentum at a fixed stellar mass. We explore the scatter within the j * –  M * plane and its correlation with both the integrated dynamical properties of a galaxy (e.g. velocity dispersion, Toomre Qg, H α star formation rate surface density ΣSFR) and its parametrized rest-frame UV / optical morphology (e.g. Sérsic index, bulge to total ratio, clumpiness, asymmetry, and concentration). We establish that the position in the j * –  M * plane is strongly correlated with the star-formation surface density and the clumpiness of the stellar light distribution. Galaxies with peculiar rest-frame UV / optical morphologies have comparable specific angular momentum to disc- dominated galaxies of the same stellar mass, but are clumpier and have higher star formation rate surface densities. We propose that the peculiar morphologies in high-redshift systems are driven by higher star formation rate surface densities and higher gas fractions leading to a more clumpy interstellar medium. [ABSTRACT FROM AUTHOR]

We investigate the contribution of clumps and satellites to the galaxy mass assembly. We analysed spatially resolved HubbleSpace Telescope observations (imaging and slitless spectroscopy) of 53 star-forming galaxies at z ∼ 1–3. We created continuum and emission line maps and pinpointed residual 'blobs' detected after subtracting the galaxy disc. Those were separated into compact (unresolved) and extended (resolved) components. Extended components have sizes ∼2 kpc and comparable stellar mass and age as the galaxy discs, whereas the compact components are 1.5 dex less massive and 0.4 dex younger than the discs. Furthermore, the extended blobs are typically found at larger distances from the galaxy barycentre than the compact ones. Prompted by these observations and by the comparison with simulations, we suggest that compact blobs are in situ formed clumps, whereas the extended ones are accreting satellites. Clumps and satellites enclose, respectively, ∼20 per cent and ≲80 per cent of the galaxy stellar mass, ∼30 per cent and ∼20 per cent of its star formation rate. Considering the compact blobs, we statistically estimated that massive clumps (M ⋆ ≳ 109 M⊙) have lifetimes of ∼650 Myr, and the less massive ones (108 < M ⋆ < 109 M⊙) of ∼145 Myr. This supports simulations predicting long-lived clumps (lifetime ≳ 100 Myr). Finally, ≲30 per cent (13 per cent) of our sample galaxies are undergoing single (multiple) merger(s), they have a projected separation ≲10 kpc, and the typical mass ratio of our satellites is 1:5 (but ranges between 1:10 and 1:1), in agreement with literature results for close pair galaxies. [ABSTRACT FROM AUTHOR]

We present 1–7 GHz high-resolution radio imaging (VLA and e-MERLIN) and spatially resolved ionized gas kinematics for 10 z < 0.2 type 2 'obscured' quasars (log [ L AGN/erg s−1] ≳ 45) with moderate radio luminosities (⁠|$\log [L_{\rm {1.4\,GHz}}$| /W Hz−1]  = 23.3–24.4). These targets were selected to have known ionized outflows based on broad [O  iii ] emission-line components (full width at half-maximum ≈ 800–1800 km s−1). Although 'radio-quiet' and not 'radio AGN' by many traditional criteria, we show that for nine of the targets, star formation likely accounts for ≲10 per cent of the radio emission. We find that ∼80–90 per cent of these nine targets exhibit extended radio structures on 1–25 kpc scales. The quasars' radio morphologies, spectral indices, and position on the radio size–luminosity relationship reveals that these sources are consistent with being low power compact radio galaxies. Therefore, we favour radio jets as dominating the radio emission in the majority of these quasars. The radio jets we observe are associated with morphologically and kinematically distinct features in the ionized gas, such as increased turbulence and outflowing bubbles, revealing jet–gas interaction on galactic scales. Importantly, such conclusions could not have been drawn from current low-resolution radio surveys such as FIRST. Our observations support a scenario where compact radio jets, with modest radio luminosities, are a crucial feedback mechanism for massive galaxies during a quasar phase. [ABSTRACT FROM AUTHOR]

We present the star formation rates (SFRs) of a sample of 109 galaxies with X-ray-selected active galactic nuclei (AGNs) with moderate to high X-ray luminosities ($$\mathrel {L_{\rm 2-8\,keV}}\,=\, 10^{42}-10^{45} \mathrel {\rm erg \, s^{-1}}$$), at redshifts 1 <  z  < 4.7, that were selected to be faint or undetected in the Herschel bands. We combine our deep Atacama large (sub-)millimetre array (ALMA) continuum observations with deblended 8–500 $$\mathrel {\rm \,\mu m}$$ photometry from Spitzer and Herschel , and use infrared (IR) spectral energy distribution (SED) fitting and AGN – star formation decomposition methods. The addition of the ALMA photometry results in an order of magnitude more X-ray AGN in our sample with a measured SFR (now 37  %). The remaining 63  % of the sources have SFR upper limits that are typically a factor of 2–10 times lower than the pre-ALMA constraints. With the improved constraints on the IR SEDs, we can now identify a mid-IR (MIR) AGN component in 50 % of our sample, compared to only ∼1  % previously. We further explore the $$F_{870\mathrel {\rm \,\mu m}}$$ / $$F_{24\mathrel {\rm \,\mu m}}$$ –redshift plane as a tool for the identification of MIR-emitting AGN, for three different samples representing AGN-dominated, star formation-dominated, and composite sources. We demonstrate that the $$F_{870\mathrel {\rm \,\mu m}}$$ / $$F_{24\mathrel {\rm \,\mu m}}$$ –redshift plane can successfully split between AGN and star formation-dominated sources, and can be used as an AGN identification method. [ABSTRACT FROM AUTHOR]

We analyse the velocity dispersion properties of 472 z ∼ 0.9 star-forming galaxies observed as part of the KMOS Redshift One Spectroscopic Survey (KROSS). The majority of this sample is rotationally dominated (83 ± 5 per cent with vC/σ0 > 1) but also dynamically hot and highly turbulent. After correcting for beam smearing effects, the median intrinsic velocity dispersion for the final sample is σ0 = 43.2 ± 0.8 km s−1 with a rotational velocity to dispersion ratio of vC/σ0  = 2.6 ± 0.1. To explore the relationship between velocity dispersion, stellar mass, star formation rate, and redshift, we combine KROSS with data from the SAMI survey (z ∼ 0.05) and an intermediate redshift MUSE sample (z ∼ 0.5). Whilst there is, at most, a weak trend between velocity dispersion and stellar mass, at fixed mass there is a strong increase with redshift. At all redshifts, galaxies appear to follow the same weak trend of increasing velocity dispersion with star formation rate. Our results are consistent with an evolution of galaxy dynamics driven by discs that are more gas rich, and increasingly gravitationally unstable, as a function of increasing redshift. Finally, we test two analytic models that predict turbulence is driven by either gravitational instabilities or stellar feedback. Both provide an adequate description of the data, and further observations are required to rule out either model. [ABSTRACT FROM AUTHOR]

We investigate the mean star formation rates (SFRs) in the host galaxies of ~3000 optically selected quasi-stellar objects (QSOs) from the Sloan Digital Sky Survey within the Herschel-ATLAS fields, and a radio-luminous subsample covering the redshift range of z = 0.2-2.5. Using Wide-field Infrared Survey Explorer (WISE) and Herschel photometry (12-500 μm) we construct composite spectral energy distributions (SEDs) in bins of redshift and active galactic nucleus (AGN) luminosity. We perform SED fitting to measure the mean infrared luminosity due to star formation, removing the contamination from AGN emission. We find that the mean SFRs show a weak positive trend with increasing AGN luminosity. However, we demonstrate that the observed trend could be due to an increase in black hole (BH) mass (and a consequent increase of inferred stellar mass) with increasing AGN luminosity. We compare to a sample of X-ray selected AGN and find that the two populations have consistent mean SFRs when matched in AGN luminosity and redshift. On the basis of the available virial BH masses, and the evolving BH mass to stellar mass relationship, we find that the mean SFRs of our QSO sample are consistent with those of main sequence star-forming galaxies. Similarly the radio-luminous QSOs have mean SFRs that are consistent with both the overall QSO sample and with star-forming galaxies on the main sequence. In conclusion, on average QSOs reside on the main sequence of star-forming galaxies, and the observed positive trend between the mean SFRs and AGN luminosity can be attributed to BH mass and redshift dependencies. [ABSTRACT FROM AUTHOR]

We present dynamical measurements from the KMOS (K-band multi-object spectrograph) Deep Survey (KDS), which comprises 77 typical star-forming galaxies at z ≅ 3.5 in the mass range 9.0 < log (M*/M⊙) < 10.5. These measurements constrain the internal dynamics, the intrinsic velocity dispersions (σint) and rotation velocities (VC) of galaxies in the high-redshift Universe. The mean velocity dispersion of the galaxies in our sample is σint = 70.8+3.3 -3.1 km s-1, revealing that the increasing average σint with increasing redshift, reported for z≅2, continues out to z≅3.5. Only 36 ± 8 per cent of our galaxies are rotation-dominated (VC/σint > 1), with the sample average VC/σint value much smaller than at lower redshift. After carefully selecting comparable star-forming samples at multiple epochs, we find that the rotationdominated fraction evolves with redshift with a z-0.2 dependence. The rotation-dominated KDS galaxies show no clear offset from the local rotation velocity-stellar mass (i.e. VC-M*) relation, although a smaller fraction of the galaxies are on the relation due to the increase in the dispersion-dominated fraction. These observations are consistent with a simple equilibrium model picture, in which random motions are boosted in high-redshift galaxies by a combination of the increasing gas fractions, accretion efficiency, specific star formation rate and stellar feedback and which may provide significant pressure support against gravity on the galactic disc scale. [ABSTRACT FROM AUTHOR]

We present a MUSE (Multi-Unit Spectroscopic Explorer) and KMOS (K-band Multi-Object Spectrograph) dynamical study 405 star-forming galaxies at redshift z = 0.28-1.65 (median redshift ... = 0.84). Our sample is representative of the star-forming 'main sequence', with star formation rates of SFR = 0.1-30 M⊙ yr-1 and stellar masses M* = 108-1011 M⊙. For 49 ± 4 per cent of our sample, the dynamics suggest rotational support, 24 ± 3 per cent are unresolved systems and 5 ± 2 per cent appear to be early-stage major mergers with components on 8-30 kpc scales. The remaining 22 ± 5 per cent appear to be dynamically complex, irregular (or face-on systems). For galaxies whose dynamics suggest rotational support, we derive inclination-corrected rotational velocities and show that these systems lie on a similar scaling between stellar mass and specific angular momentum as local spirals with j* = J/M* ∝ M*2/3 but with a redshift evolution that scales as j* ∝ M*2/3 (1 + z)-1. We also identify a correlation between specific angular momentum and disc stability such that galaxies with the highest specific angular momentum (log(j*/M*2/3) > 2.5) are the most stable, with Toomre Q = 1.10 ± 0.18, compared to Q = 0.53 ± 0.22 for galaxies with log(j*/M*2/3) < 2.5. At a fixed mass, the Hubble Space Telescope morphologies of galaxies with the highest specific angular momentum resemble spiral galaxies, whilst those with low specific angular momentum are morphologically complex and dominated by several bright star-forming regions. This suggests that angular momentum plays a major role in defining the stability of gas discs: at z ~ 1, massive galaxies that have discs with low specific angular momentum are globally unstable, clumpy and turbulent systems. In contrast, galaxies with high specific angular momentum have evolved into stable discs with spiral structure where star formation is a local (rather than global) process. [ABSTRACT FROM AUTHOR]

We present the first results from the KMOS (K-band Multi-Object Spectrograph) AGN (active galactic nuclei) Survey at High redshift (KASHz), a VLT/KMOS integral-field spectroscopic (IFS) survey of z ≳ 0.6 AGN. We present galaxy-integrated spectra of 89 X-ray AGN (L2-10 keV = 1042-1045 erg s-1), for which we observed [O III] (z ≈ 1.1-1.7) or Ha emission (z ≈ 0.6-1.1). The targets have X-ray luminosities representative of the parent AGN population and we explore the emission-line luminosities as a function of X-ray luminosity. For the [O III] targets,≈50 per cent have ionized gas velocities indicative of gas that is dominated by outflows and/or highly turbulent material (i.e. overall line widths≳600 km s-1). The most luminous half (i.e. LX > 6 × 1043 erg s-1) have a ≳2 times higher incidence of such velocities. On the basis of our results, we find no evidence that X-ray obscured AGN are more likely to host extreme kinematics than unobscured AGN. Our KASHz sample has a distribution of gas velocities that is consistent with a luminosity-matched sample ofz<0.4 AGN. This implies little evolution in the prevalence of ionized outflows, for a fixed AGN luminosity, despite an order-of-magnitude decrease in average star formation rates over this redshift range. Furthermore, we compare our Ha targets to a redshift-matched sample of star-forming galaxies and despite a similar distribution of Ha luminosities and likely star formation rates, we find extreme ionized gas velocities are up to ≈10 times more prevalent in the AGN-host galaxies. Our results reveal a high prevalence of extreme ionized gas velocities in high-luminosity X-ray AGN and imply that the most powerful ionized outflows in high-redshift galaxies are driven by AGN activity. [ABSTRACT FROM AUTHOR]

We present the infrared (IR) and X-ray properties of a sample of 33 mid-IR luminous quasars (νL6μm ≥ 6 × 1044 erg s-1) at redshift z ≈ 1-3, identified through detailed spectral energy distribution analyses of distant star-forming galaxies, using the deepest IR data from Spitzer and Herschel in the GOODS-Herschel fields. The aim is to constrain the fraction of obscured, and Compton-thick (CT, NH >1.5×1024 cm-2) quasars at the peak era of nuclear and star formation activities. Despite being very bright in the mid-IR band, ≈30 per cent of these quasars are not detected in the extremely deep 2 and 4 Ms Chandra X-ray data available in these fields. X-ray spectral analysis of the detected sources reveals that the majority (≈67 per cent) are obscured by column densities NH >1022 cm-2; this fraction reaches80 per cent when including the X-ray-undetected sources (9 out of 33), which are likely to be the most heavily obscured, CT quasars. We constrain the fraction of CT quasars in our sample to be ≈24-48 per cent, and their space density to be ɸ = (6.7 ± 2.2) × 10-6 Mpc-3. From the investigation of the quasar host galaxies in terms of star formation rates (SFRs) and morphological distortions, as a sign of galaxy mergers/interactions, we do not find any direct relation between SFRs and quasar luminosity or X-ray obscuration. On the other hand, there is tentative evidence that the most heavily obscured quasars have, on average, more disturbed morphologies than the unobscured moderately obscured quasar hosts, which preferentially live in undisturbed systems. However, the fraction of quasars with disturbed morphology amongst the whole sample is ≈40 per cent, suggesting that galaxy mergers are not the main fuelling mechanism of quasars at z ≈ 2. [ABSTRACT FROM AUTHOR]

We study the 850-μm emission in X-ray-selected active galactic nuclei (AGN) in the ~2 deg² COSMOS field using new data from the SCUBA-2 Cosmology Legacy Survey. We find 19 850-μm bright X-ray AGN in a 'high-sensitivity' region covering 0.89 deg² with flux densities of S850 = 4-10 mJy. The 19 AGN span the full range in redshift and hard X-ray luminosity covered by the sample - 0.7 ≲ z ≲ 3.5 and 43.2 ≲ log10(LX) ≲ 45. We report a highly significant stacked 850-μm detection of a hard X-ray flux-limited population of 699 z > 1 X-ray AGN - S850 = 0.71 ± 0.08 mJy. We explore trends in the stacked 850-μm flux densities with redshift, finding no evolution in the average cold dust emission over the redshift range probed. For type 1 AGN, there is no significant correlation between the stacked 850-μm flux and hard X-ray luminosity. However, in type 2 AGN the stacked submillimeter flux is a factor of 2 higher at high luminosities. When averaging over all X-ray luminosities, no significant differences are found in the stacked submillimeter fluxes of type 1 and type 2 AGN as well as AGN separated on the basis of X-ray hardness ratios and optical-to-infrared colours. However, at log10(L2 - 10/erg s-1) > 44.4, dependences in average submillimeter flux on the optical-to-infrared colours become more pronounced. We argue that these high-luminosity AGN represent a transition from a secular to a merger-driven evolutionary phase where the star formation rates and accretion luminosities are more tightly coupled. Stacked AGN 850-μm fluxes are compared to the stacked fluxes of a mass-matched sample of K-band-selected non-AGN galaxies. We find that at 10.5 10(M*/M⊙)<11.5, the non-AGN 850-μm fluxes are 1.5-2 times higher than in type 2 AGN of equivalent mass. We suggest these differences are due to the presence of massive dusty, red starburst galaxies in the K-band-selected non-AGN sample, which are not present in optically selected catalogues covering a smaller area. [ABSTRACT FROM AUTHOR]

We present integral field unit observations covering the [O iii]λλ4959, 5007 and Hβ emission lines of 16 z < 0.2 type 2 active galactic nuclei (AGN). Our targets are selected from a well-constrained parent sample of ≈24 000 AGN so that we can place our observations into the context of the overall AGN population. Our targets are radio quiet with star formation rates (SFRs; ≲[10–100] M⊙ yr−1) that are consistent with normal star-forming galaxies. We decouple the kinematics of galaxy dynamics and mergers from outflows. We find high-velocity ionized gas (velocity widths ≈600–1500 km s−1; maximum velocities ≤1700 km s−1) with observed spatial extents of ≳(6–16) kpc in all targets and observe signatures of spherical outflows and bi-polar superbubbles. We show that our targets are representative of z < 0.2, luminous (i.e. L[O iii] > 1041.7 erg s−1) type 2 AGN and that ionized outflows are not only common but also in ≥70 per cent (3σ confidence) of cases, they are extended over kiloparsec scales. Our study demonstrates that galaxy-wide energetic outflows are not confined to the most extreme star-forming galaxies or radio-luminous AGN; however, there may be a higher incidence of the most extreme outflow velocities in quasars hosted in ultraluminous infrared galaxies. Both star formation and AGN activity appear to be energetically viable to drive the outflows and we find no definitive evidence that favours one process over the other. Although highly uncertain, we derive mass outflow rates (typically ≈10 times the SFRs), kinetic energies (≈0.5–10 per cent of LAGN) and momentum rates (typically ≳10–20 × LAGN/c) consistent with theoretical models that predict AGN-driven outflows play a significant role in shaping the evolution of galaxies. [ABSTRACT FROM AUTHOR]

We present results from a≈100 ks Chandra observation of the 2QZ Cluster 1004+00 structure at z = 2.23 (hereafter 2QZ Clus). 2QZ Clus was originally identified as an overdensity of four optically-selected QSOs at z = 2.23 within a 15 × 15 arcmin2 region. Narrow-band imaging in the near-IR (within the K band) revealed that the structure contains an additional overdensity of 22 z = 2.23 Hα-emitting galaxies (HAEs), resulting in 23 unique z = 2.23 HAEs/QSOs (22 within the Chandra field of view). Our Chandra observations reveal that three HAEs in addition to the four QSOs harbor powerfully accreting supermassive black holes (SMBHs), with 2-10 keV luminosities of ≈(8-60) × 1043 erg s-1 and X-ray spectral slopes consistent with unobscured active galactic nucleus (AGN). Using a large comparison sample of 210 z = 2.23 HAEs in the Chandra-COSMOS field (C-COSMOS), we find suggestive evidence that the AGN fraction increases with local HAE galaxy density. The 2QZ Clus HAEs reside in a moderately overdense environment (a factor of ≈2 times over the field), and after excluding optically-selected QSOs, we find that the AGN fraction is a factor of ≈3.5+3.8 times higher than C-COSMOS HAEs in similar environments. Using stacking analyses of the Chandra data and Herschel SPIRE observations at 250μm, we respectively estimate mean SM-2.2 accretion rates ( MBH) and star formation rates (SFRs) for the 2QZ Clus and C-COSMOS samples. We find that the mean 2QZ Clus HAE stacked X-ray luminosity is QSO-like (L2-10 keV ≈ [6-10] × 10BH) and star formation rates (SFRs) for the 2QZ Clus and C-COSMOS samples. We find that the mean 2QZ Clus HAE stacked X-ray luminosity is QSO-like (L2-10 keV ≈ [6-10] × 1043), and the implied M-1), and the implied MBH/SFR ≈ (1.6-3.2) × 10-3/" relation and z ≈ 2 X-ray selected AGN. In contrast, the C-COSMOS HAEs are on average an order of magnitude less X-ray luminous and have MBH/" relation and z ≈ 2 X-ray selected AGN. In contrast, the C-COSMOS HAEs are on average an order of magnitude less X-ray luminous and have MBH, somewhat lower than the local M-3/" relation, but comparable to that found for z ≈ 1-2 star-forming galaxies with similar mean X-ray luminosities. We estimate that a periodic QSO phase with duty cycle ≈2%-8% would be sufficient to bring star-forming galaxies onto the local MBH/"I relation. This duty cycle is broadly consistent with the observed C-COSMOS HAE AGN fraction (≈0.4%-2.3%) for powerful AGN with LX ≳ 10BH/"I relation. This duty cycle is broadly consistent with the observed C-COSMOS HAE AGN fraction (≈0.4%-2.3%) for powerful AGN with LX ≳ 1044 erg s-1. Future observations of 2QZ Clus will be needed to identify key factors responsible for driving the mutual growth of the SMBHs and galaxies. [ABSTRACT FROM AUTHOR]