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Polar dust has been discovered in a number of local active galactic nuclei (AGN), with radiation-driven torus models predicting a wind to be its main driver. However, little is known about its characteristics, spatial extent, or connection to the larger scale outflows. We present the first JWST /MIRI study aimed at imaging polar dust by zooming on to the centre of ESO 428-G14, part of the Galaxy Activity, Torus, and Outflow Survey (GATOS) survey of local AGN. We detect extended mid-infrared (MIR) emission within 200 pc from the nucleus. This polar structure is co-linear with a radio jet and lies perpendicular to a molecular gas lane that feeds and obscures the nucleus. Its morphology bears a striking resemblance to that of gas ionized by the AGN in the narrow-line region. We demonstrate that part of this spatial correspondence is due to contamination within the JWST filter bands from strong emission lines. Correcting for the contamination, we find the morphology of the dust continuum to be more compact, though still clearly extended out to |$r\approx 100 \, \rm pc$|⁠. We estimate the emitting dust has a temperature of |$\sim 120\, \rm K$|⁠. Using simple models, we find that the heating of small dust grains by the radiation from the central AGN and/or radiative jet-induced shocks is responsible for the extended MIR emission. Radiation-driven dusty winds from the torus is unlikely to be important. This has important implications for scales to which AGN winds can carry dust and dense gas out into their host galaxies. [ABSTRACT FROM AUTHOR]

Understanding the links between different phases of outflows from active galactic nuclei is a key goal in extragalactic astrophysics. Here, we compare [O  iii ]  |$\lambda \lambda$| 4960, 5008 outflow signatures in quasars with and without broad absorption lines (BALs), aiming to test how the broad absorption troughs seen in the rest-frame ultraviolet are linked to the narrow line region outflows seen in the rest-frame optical. We present new near-infrared spectra from Magellan/FIRE that cover [O  iii ] in 12 quasars with |$2.1\lt z\lt 2.3$|⁠ , selected to have strong outflow signatures in C  iv |$\lambda$| 1550. Combining with data from the literature, we build a sample of 73 BAL, 115 miniBAL, and 125 non-BAL quasars with |$1.5\lt z\lt 2.6$|⁠. The strength and velocity width of [O  iii ] correlate strongly with the C  iv emission properties, but no significant difference is seen in the [O  iii ] emission-line properties between the BALs, non-BALs, and miniBALs once the dependence on C  iv emission is taken into account. A weak correlation is observed between the velocities of C  iv BALs and [O  iii ] emission, which is accounted for by the fact that both outflow signatures correlate with the underlying C  iv emission properties. Our results add to the growing evidence that BALs and non-BALs are drawn from the same parent population and are consistent with a scenario wherein BAL troughs are intermittent tracers of persistent quasar outflows, with a part of such outflow becoming optically thick along our line of sight for sporadic periods of time within which BALs are observed. [ABSTRACT FROM AUTHOR]

We present the first systematic broad-band X-ray study of super-Eddington accretion onto supermassive black holes with simultaneous NuSTAR and XMM–Newton or Swift /XRT observations of a sample of eight super-Eddington accreting Active Galactic Nuclei (AGNs) with Eddington ratio 1 < λ Edd < 426. We find that the super-Eddington accreting massive black holes (SEAMBHs) show a steep primary continuum slope as expected for sources accreting in the super-Eddington regime, mostly dominated by relativistic reflection. The iron K α emission lines of the sources of our sample show relativistic broadening. In addition, the equivalent widths of the narrow components of the iron K α lines follow the 'X-ray Baldwin' effect, also known as the 'Iwasawa–Taniguchi' effect. We found a statistically significant correlation between the photon index of the primary power law and the Eddington ratio, consistent with past studies. Moreover, as expected for super-Eddington sources, the median value of the reflection fraction of the sources we analysed is a factor ∼ 2 higher than the median reflection fraction value of the type 1 AGN from the BASS sample. We are able to estimate the coronal temperature for three sources of our sample: Mrk 382 (kT e = 7.75 keV), PG 0026+129 (kT e = 39 keV), and IRAS 04416+1215 (kT e = 2.95 keV). Looking at the position of the SEAMBHs sources of our sample in the compactness–temperature diagram it appears that in super-Eddington AGN, as for lower Eddington ratio AGN, the X-ray corona is controlled by pair production and annihilation. [ABSTRACT FROM AUTHOR]

Changing-look (CL) AGN are unique probes of accretion onto supermassive black holes (SMBHs), especially when simultaneous observations in complementary wavebands allow investigations into the properties of their accretion flows. We present the results of a search for CL behaviour in 412 Swift -BAT detected AGN with multiple epochs of optical spectroscopy from the BAT AGN Spectroscopic Survey (BASS). 125 of these AGN also have 14–195  keV ultra-hard X-ray light curves from Swift -BAT which are contemporaneous with the epochs of optical spectroscopy. Eight CL events are presented for the first time, where the appearance or disappearance of broad Balmer line emission leads to a change in the observed Seyfert type classification. Combining with known events from the literature, 21 AGN from BASS are now known to display CL behaviour. Nine CL events have 14–195  keV data available, and five of these CL events can be associated with significant changes in their 14–195  keV flux from BAT. The ultra-hard X-ray flux is less affected by obscuration and so these changes in the 14–195 keV band suggest that the majority of our CL events are not due to changes in line-of-sight obscuration. We derive a CL rate of 0.7–6.2 per cent on 10–25 yr time-scales, and show that many transitions happen within at most a few years. Our results motivate further multiwavelength observations with higher cadence to better understand the variability physics of accretion onto SMBHs. [ABSTRACT FROM AUTHOR]

We present a detailed study of the highly obscured active galaxy NGC 4507, performed using four Nuclear Spectroscopic Telescope Array (NuSTAR) observations carried out between May and August in 2015 (∼130 ks in total). Using various phenomenological and physically motivated torus models, we explore the properties of the X-ray source and those of the obscuring material. The primary X-ray emission is found to be non-variable, indicating a stable accretion during the period of the observations. We find the equatorial column density of the obscuring materials to be ∼2 × 1024 cm−2 while the line-of-sight column density to be ∼7–8 × 1023 cm−2. The source is found to be deeply buried with the torus covering factor of ∼0.85. We observe variability in the line-of-sight column density on a time-scale of <35 d. The covering factor of the Compton-Thick material is found to be ∼0.35 in agreement with the results of recent X-ray surveys. From the variability of the line-of-sight column density, we estimate that the variable absorbing material is likely located either in the BLR or in the torus. [ABSTRACT FROM AUTHOR]

Reprocessed X-ray emission in active galactic nuclei can provide fundamental information about the circumnuclear environments of supermassive black holes. Recent mid-infrared studies have shown evidence of an extended dusty structure perpendicular to the torus plane. In this work, we build a self-consistent X-ray model for the Circinus Galaxy including the different physical components observed at different wavelengths and needed to reproduce both the morphological and spectral properties of this object in the mid-infrared. The model consists of four components: the accretion disc, the broad-line region (BLR), a flared disc in the equatorial plane, and a hollow cone in the polar direction. Our final model reproduces well the 3–70 keV Chandra and NuSTAR spectra of Circinus, including the complex Fe Kα zone and the spectral curvature, although several additional Gaussian lines, associated with either ionized iron or broadened Fe Kα/Kβ lines, are needed. We find that the flared disc is Compton-thick (⁠|$N_{\rm H,d}= \rm 1.01^{+0.03}_{-0.24}\times 10^{25}\, cm^{-2}$|⁠) and geometrically thick (⁠|$\mathrm{ CF}=0.55^{+0.01}_{-0.05}$|⁠), and that the hollow cone has a Compton-thin column density (⁠|$N_{\rm H,c}= \rm 2.18^{+0.47}_{-0.43}\times 10^{23}\, cm^{-2}$|⁠), which is consistent with the values inferred by mid-infrared studies. Including also the BLR, the effective line-of-sight column density is |$N_{\rm H}= \rm 1.47^{+0.03}_{-0.24}\times 10^{25}\, cm^{-2}$|⁠. This approach to X-ray modelling, i.e. including all the different reprocessing structures, will be very important to fully exploit data from future X-ray missions. [ABSTRACT FROM AUTHOR]

We present new Nuclear Spectroscopic Telescope Array (NuSTAR) observations of the core of IC 2497, the galaxy associated with Hanny's Voorwerp. The combined fits of the Chandra (0.5-8 keV) and NuSTAR (3-24 keV) X-ray spectra, together with WISE mid-IR photometry, optical longslit spectroscopy and optical narrow-band imaging, suggest that the galaxy hosts a Compton-thick active galactic nucleus (AGN) (NH ~ 2 x 1024 cm-2, current intrinsic luminosity Lbol ~ 2-5 x 1044 erg s-1) whose luminosity dropped by a factor of ~50 within the last ~100 kyr. This corresponds to a change in Eddington ratio (ER) from λEdd ~ 0.35 to λEdd ~ 0.007. We argue that the AGN in IC 2497 should not be classified as a changinglook AGN, but rather we favour the interpretation where the AGN is undergoing a change in accretion state (from radiatively efficient to radiatively inefficient). In this scenario, the observed drop in luminosity and ER corresponds to the final stage of an AGN accretion phase. Our results are consistent with previous studies in the optical, X-ray and radio although the magnitude of the drop is lower than previously suggested. In addition, we discuss a possible analogy between X-ray binaries and an AGN. [ABSTRACT FROM AUTHOR]

We study the relation between accretion rate (in terms of L/LEdd) and shape of the hard X-ray spectral energy distribution (namely the photon index Γx) for a large sample of 228 hard X-ray-selected, low-redshift active galactic nuclei (AGNs), drawn from the Swift/BAT AGN Spectroscopic Survey (BASS). This includes 30 AGNs for which black hole mass (and therefore L/LEdd) is measured directly through masers, spatially resolved gas or stellar dynamics, or reverberation mapping. The high-quality and broad energy coverage of the data provided through BASS allow us to examine several alternative determinations of both Γx and L/LEdd. For the BASS sample as a whole, we find a statistically significant, albeit very weak correlation between Γx and L/LEdd. The best-fitting relations we find, Γx ≅ 0.15 log L/LEdd + const., are considerably shallower than those reported in previous studies. Moreover, we find no corresponding correlations among the subsets of AGN with different MBH determination methodology. In particular, we find no robust evidence for a correlation when considering only those AGN with direct or single-epoch MBH estimates. This latter finding is in contrast to several previous studies which focused on z > 0.5 broad-line AGN. We discuss this tension and conclude that it can be partially accounted for if one adopts a simplified, power-law X-ray spectral model, combined with L/LEdd estimates that are based on the continuum emission and on single-epoch broad-line spectroscopy in the optical regime. We finally highlight the limitations on using Γx as a probe of supermassive black hole evolution in deep extragalactic X-ray surveys. [ABSTRACT FROM AUTHOR]

We investigate the observed relationship between black hole mass (MBH), bolometric luminosity (Lbol) and Eddington ratio (λEdd) with optical emission-line ratios ([N II] λ6583/Ha, [S II] λλ6716, 6731/Hα, [OI] λ6300/Hα, [OIII] λ5007/Hβ, [Ne III] λ3869/Hβ and He II λ4686/Hβ) of hard X-ray-selected active galactic nuclei (AGN) from the BAT AGN Spectroscopic Survey. We show that the [N II] λ6583/Hα ratio exhibits a significant correlation with λEdd (RPear = -0.44, p-value = 3 × 10-13, σ = 0.28 dex), and the correlation is not solely driven by MBH or Lbol. The observed correlation between [N II] λ6583/Hα ratio and MBH is stronger than the correlation with Lbol, but both are weaker than the λEdd correlation. This implies that the large-scale narrow lines of AGN host galaxies carry information about the accretion state of the AGN central engine. We propose that [N II] λ6583/Hα is a useful indicator of Eddington ratio with 0.6 dex of rms scatter, and that it can be used to measure λEdd and thus MBH from the measured Lbol, even for high-redshift obscured AGN.We briefly discuss possible physical mechanisms behind this correlation, such as the mass-metallicity relation, X-ray heating, and radiatively driven outflows. [ABSTRACT FROM AUTHOR]