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We present observations of the type-2 Seyfert NGC 7172 obtained with the medium-resolution spectrometer (MRS) of the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope (JWST). This galaxy hosts one of the lowest ionised gas mass outflow rates (Ṁout ∼ 0.005 M⊙ yr−1) in a sample of six active galactic nuclei (AGN) with similar bolometric luminosities (log Lbol ∼ 44 erg s−1) within the Galactic Activity, Torus, and Outflow Survey (GATOS). We aim to understand the properties of the ionised gas outflow and its impact on the host galaxy. We mainly used the ionised gas emission lines from the neon transitions, which cover a broad range of ionisation potentials (IPs) from ∼20 eV to ∼130 eV. We applied parametric and non-parametric methods to characterise the line emission and kinematics. The low excitation lines (IP < 25 eV, e.g. [Ne II]) trace the rotating disc emission. The high excitation lines (IP > 90 eV, e.g. [Ne V]), which are likely photoionised exclusively by the AGN, are expanding in the direction nearly perpendicular to the disc of the galaxy, with maximum projected velocities in the range of ∼350–500 km s−1. In particular, [Ne V] and [Ne VI] lines reveal a biconical ionised gas outflow emerging north-south from the nuclear region, extending at least ∼2.5″ N and 3.8″ S (projected distance of ∼450 and 680 pc, respectively). Most of the emission arising in the northern part of the cone was not previously detected due to obscuration. Given the almost face-on orientation of the outflow and the almost edge-on orientation of the galaxy, NGC 7172 may be a case of weak coupling. Nevertheless, we found evidence of positive feedback in two distinct outflowing clumps at projected distances of 3.1″ and 4.3″ (i.e. ∼560 and 780 pc) south-west of the AGN. We estimated a star formation rate in these regions using the [Ne II] and [Ne III] luminosities of 0.08 M⊙ yr−1, which is ∼10% of that found in the circumnuclear ring. The star formation activity might have been triggered by the interaction between the ionised gas outflow and the interstellar medium of the galaxy. [ABSTRACT FROM AUTHOR]

Context. Understanding how gas flows into galactic centres, fuels the active galactic nucleus (AGN), and is in turn expelled back through feedback processes is of great importance to appreciate the role AGN play in the growth and evolution of galaxies. Aims. We use Multi Unit Spectroscopic Explorer-adaptive optics (MUSE-AO) optical spectra of the inner 7″​.5 × 7″​.5 (1.3 kpc × 1.3 kpc) of the nearby Seyfert 1 galaxy NGC 4593 to characterise its ionised gas kinematics. Methods. We fitted single-Gaussian components to the [O III] λ5007 and [N II] λ6583 emission lines, and double-Gaussian components to Hα and Hβ to determine the main ionisation mechanism of the gas. To determine the kinematics of the ionised gas, we fit double-Gaussian components to the [O III] λ5007 line. Results. The high angular resolution MUSE data (∼0″​​​​. 12 = 20 pc) capture structures of the circumnuclear region including the innermost spiral that feeds the nucleus. Based on the stellar kinematic maps, we confirm the presence of a rotating disc, whilst for the ionised gas, we find high-velocity dispersion values of up to 200 − 250 km s−1 that show that part of the gas is highly perturbed. The dominant ionisation mechanism of the gas is AGN photoionisation, which reaches the highest values within the innermost 4″ (680 pc) diameter of the galaxy. At larger radii, the emission line ratios correspond to values in the composite region of the Baldwin, Phillips and Terlevich (BPT) diagram. Conclusions. The broad-component of [O III] λ5007 shows blue-shifted velocities on the east side of the central 2″ (340 pc), which spatially coincide with a region of high velocity-dispersion. This confirms the presence of outflowing gas. We estimate a mass outflow rate and kinetic power of Ṁ ≥ 0.048 M⊙ yr−1 and Ėkin ≥ 4.09 × 1039 erg s−1. The derived mass outflow rate is consistent with that expected from empirical relations between mass outflow rate and AGN luminosity for a low-luminosity AGN such as NGC 4593. High angular resolution integral field observations can enable multi-component analysis of the innermost regions of galaxies, allowing a detailed view of ionised gas flows. [ABSTRACT FROM AUTHOR]

The triggering mechanism for the most luminous, quasar-like active galactic nuclei (AGN) remains a source of debate, with some studies favouring triggering via galaxy mergers, but others finding little evidence to support this mechanism. Here, we present deep Isaac Newton Telescope/Wide Field Camera imaging observations of a complete sample of 48 optically selected type 2 quasars – the QSOFEED sample (⁠|$L_{\rm [O\, \small {III}]}\gt 10^{8.5}\, \mathrm{L}_{\odot }$|⁠ ; z < 0.14). Based on visual inspection by eight classifiers, we find clear evidence that galaxy interactions are the dominant triggering mechanism for quasar activity in the local universe, with 65 |$^{+6}_{-7}$|  per cent of the type 2 quasar hosts showing morphological features consistent with galaxy mergers or encounters, compared with only 22 |$^{+5}_{-4}$|  per cent of a stellar-mass- and redshift-matched comparison sample of non-AGN galaxies – a 5σ difference. The type 2 quasar hosts are a factor of 3.0 |$^{+0.5}_{-0.8}$| more likely to be morphologically disturbed than their matched non-AGN counterparts, similar to our previous results for powerful 3CR radio AGN of comparable [O  iii ] emission-line luminosity and redshift. In contrast to the idea that quasars are triggered at the peaks of galaxy mergers as the two nuclei coalesce, and only become visible post-coalescence, the majority of morphologically disturbed type 2 quasar sources in our sample are observed in the pre-coalescence phase (61 |$^{+8}_{-9}$|  per cent). We argue that much of the apparent ambiguity that surrounds observational results in this field is a result of differences in the surface brightness depths of the observations, combined with the effects of cosmological surface brightness dimming. [ABSTRACT FROM AUTHOR]

Studies indicate strong evidence of a scaling relation in the local Universe between the supermassive black hole mass (MBH) and the stellar mass of their host galaxies (M. They even show similar histories across cosmic times of their differential terms: the star formation rate (SFR) and black hole accretion rate (BHAR). However, a clear picture of this coevolution is far from being understood. We selected an X-ray sample of active galactic nuclei (AGN) up to z = 2.5 in the miniJPAS footprint. Their X-ray to infrared spectral energy distributions (SEDs) have been modeled with the CIGALE code, constraining the emission to 68 bands, from which 54 are the narrow filters from the miniJPAS survey. For a final sample of 308 galaxies, we derived their physical properties, such as their M SFR, star formation history (SFH), and the luminosity produced by the accretion process of the central BH (LAGN). For a subsample of 113 sources, we also fit their optical spectra to obtain the gas velocity dispersion from the broad emission lines and estimated the MBH. We calculated the BHAR in physical units depending on two radiative effciency regimes. We find that the Eddington ratios (-Edd) and its popular proxy (LX=M) have a difference of 0.6 dex, on average, and a KS test indicates that they come from different distributions. Our sources exhibit a considerable scatter on the MBHMscaling relation, which can explain the difference between -Edd and its proxy. We also modeled three evolution scenarios for each source to recover the integral properties at z = 0. Using the SFR and BHAR, we show a notable diminution in the scattering between MBHM For the last scenario, we considered the SFH and a simple energy budget for the AGN accretion, and we retrieved a relation similar to the calibrations known for the local Universe. Our study covers ~1 deg2 in the sky and is sensitive to biases in luminosity. Nevertheless, we show that, for bright sources, the link between the differential values (SFR and BHAR) and their decoupling based on an energy limit is the key that leads to the local MBHMscaling relation. In the future, we plan to extend this methodology to a thousand degrees of the sky using JPAS with an X-ray selection from eROSITA, to obtain an unbiased distribution of BHAR and Eddington ratios. [ABSTRACT FROM AUTHOR]

Investigation of the triggering mechanisms of radio active galactic nuclei (radio AGN) is important for improving our general understanding of galaxy evolution. In the first paper in this series, detailed morphological analysis of high-excitation radio galaxies (HERGs) with intermediate radio powers suggested that the importance of triggering via galaxy mergers and interactions increases strongly with AGN radio power and weakly with optical emission-line luminosity. Here, we use an online classification interface to expand our morphological analysis to a much larger sample of 155 active galaxies (3CR radio galaxies, radio-intermediate HERGs, and Type 2 quasars) that covers a broad range in both 1.4 GHz radio power and [O  iii ] λ5007 emission-line luminosity. All active galaxy samples are found to exhibit excesses in their rates of morphological disturbance relative to 378 stellar-mass- and redshift-matched non-active control galaxies classified randomly and blindly alongside them. These excesses are highest for the 3CR HERGs (4.7σ) and Type 2 quasar hosts (3.9σ), supporting the idea that galaxy mergers provide the dominant triggering mechanism for these subgroups. When the full active galaxy sample is considered, there is clear evidence to suggest that the enhancement in the rate of disturbance relative to the controls increases strongly with [O  iii ] λ5007 emission-line luminosity but not with 1.4 GHz radio power. Evidence that the dominant AGN host types change from early-type galaxies at high radio powers to late-type galaxies at low radio powers is also found, suggesting that triggering by secular, disc-based processes holds more importance for lower-power radio AGN. [ABSTRACT FROM AUTHOR]

Active galactic nuclei (AGN) are a key ingredient for understanding galactic evolution, as their activity is coupled to the host galaxy properties through feedback processes. AGN-driven outflows are one of the manifestations of this feedback. The laser guide star adaptive optics mode for MUSE at the VLT now permits us to study the innermost tens of parsecs of nearby AGN in the optical. We present a detailed analysis of the ionised gas in the central regions of NGC 7130, which is an archetypical composite Seyfert and nuclear starburst galaxy at a distance of 64.8 Mpc. We achieve an angular resolution of 0.​​″17, corresponding to roughly 50 pc. We performed a multi-component analysis of the main interstellar medium emission lines in the wavelength range of MUSE and identified nine kinematic components, six of which correspond to the AGN outflow. The outflow is biconic, oriented in an almost north–south direction, and has velocities of a few 100 km s−1 with respect to the disc of NGC 7130. The lobe length is at least 3″(∼900 pc). We decomposed the approaching side of the outflow into a broad and a narrow component with typical velocity dispersions below and above ∼200 km s−1, respectively. The blueshifted narrow nomponent has a sub-structure, in particular a collimated plume traced especially well by [O III]. The plume is aligned with the radio jet, indicating that it may be jet powered. The redshifted lobe is composed of two narrow components and a broad component. An additional redshifted component is seen outside the main north-south axis, about an arcsecond east of the nucleus. Line ratio diagnostics indicate that the outflow gas in the north–south axis is AGN powered, whereas the off-axis component has LINER properties. We hypothesise that this is because the radiation field that reaches off-axis clouds has been filtered by clumpy ionised clouds found between the central engine and the low-ionisation emitting region. If we account for all the outflow components (the blueshifted components), the ionised gas mass outflow rate is Ṁ = 1.5 ± 0.9 M⊙ yr−1 (Ṁ = 0.55 ± 0.55 M⊙ yr−1), and the kinetic power of the AGN is Ėkin = (3.4 ± 2.5) × 1041 erg s−1 (Ėkin = (8.8 ± 5.9) × 1040 erg s−1), which corresponds to Fkin = 0.15 ± 0.11% (Fkin = 0.040 ± 0.027%) of the bolometric AGN power. The broad components, those with a velocity dispersion of σ >  200 km s−1, carry ∼2/3 (∼90%) of the mass outflow, and ∼90% (∼98%) of the kinetic power. The combination of high-angular-resolution integral field spectroscopy and a careful multi-component decomposition allows a uniquely detailed view of the outflow in NGC 7130, illustrating that AGN kinematics are more complex than those traditionally derived from less sophisticated data and analyses. [ABSTRACT FROM AUTHOR]

Active galactic nuclei (AGNs) with intermediate radio powers are capable of driving multiphase outflows in galaxy bulges, and are also more common than their high-radio-power counterparts. In-depth characterization of the typical host galaxies and likely triggering mechanisms for this population is therefore required in order to better understand the role of radio AGN feedback in galaxy evolution. Here, we use deep optical imaging data to study the detailed host morphologies of a complete sample of 30 local radio AGNs with high-excitation optical emission (HERG) spectra and intermediate radio powers [ z < 0.1; 22.5 < log(⁠|$L_{\rm 1.4GHz}$|⁠) < 24.0 W Hz-1]. The fraction of hosts with morphological signatures of mergers and interactions is greatly reduced compared to the 2Jy radio-powerful galaxies [log(⁠|$L_{\rm 1.4GHz}$|⁠) > 25.0 W Hz-1] with strong optical emission lines: 53 ± 9 per cent compared with 94 ± 4 per cent. In addition, the most radio-powerful half of the sample has a higher frequency of morphological disturbance than the least radio-powerful half (67 ± 12 per cent and 40 ± 13 per cent, respectively), including the eight most highly disturbed galaxies. This suggests that the importance of triggering nuclear activity in high-excitation radio galaxies (HERGs) through mergers and interactions reduces with radio power. Both visual inspection and detailed light profile modelling reveal a mixed population of early-type and late-type morphologies, contrary to the massive elliptical galaxy hosts of radio-powerful AGNs. The prevalence of late-type hosts could suggest that triggering via secular, disc-based processes has increased importance for HERGs with lower radio powers (e.g. disc instabilities and large-scale bars). [ABSTRACT FROM AUTHOR]

Based on new near-infrared spectroscopic data from the instrument Espectrógrafo Multiobjeto Infra-Rojo (EMIR) on the 10.4 m Gran Telescopio Canarias, we report the presence of an ionized and warm molecular outflow in the luminous type-2 quasar J150904.22+043441.8 (z = 0.1118). The ionized outflow is faster than its molecular counterpart, although the outflow sizes that we derive for them are consistent within the errors (1.34 ± 0.18 and 1.46 ± 0.20 kpc, respectively). We use these radii, the broad emission-line luminosities and in the case of the ionized outflow, the density calculated from the trans-auroral [O  ii ] and [S  ii ] lines, to derive mass outflow rates and kinetic coupling efficiencies. While the ionized and warm molecular outflows represent a small fraction of the AGN power (≤0.033 and 0.0001 per cent of L bol, respectively), the total molecular outflow, whose mass is estimated from an assumed warm-to-cold gas mass ratio of 6 × 10−5, has a kinetic coupling efficiency of ∼1.7 per cent L bol. Despite the large uncertainty, this molecular outflow represents a significant fraction of L bol and it could potentially have a significant impact on the host galaxy. In addition, the quasar spectrum reveals bright and patchy narrow Paα emission extending out to 4 arcsec (8 kpc) south-east and north-west from the active nucleus. [ABSTRACT FROM AUTHOR]

A suite of 432 collisionless simulations of bound pairs of spiral galaxies with mass ratios 1:1 and 3:1, and global properties consistent with the ΛCDM paradigm, is used to test the conjecture that major mergers fuel the dual AGN (DAGN) of the local volume. Our analysis was based on the premise that the essential aspects of this scenario can be captured by replacing the physics of the central black holes with restrictions on their relative separation in phase space. We introduce several estimates of the DAGN fraction and infer predictions for the activity levels and resolution limits usually involved in surveys of these systems, assessing their dependence on the parameters controlling the length of both mergers and nuclear activity. Given a set of constraints, we find that the values adopted for some of the latter factors often condition the outcomes from individual experiments. Still, the results do not, in general, reveal very tight correlations, the clearest effect being the tendency of the frequencies normalized to the merger time to anticorrelate with the orbital circularity. In agreement with other theoretical studies, our simulations predict intrinsic DAGN abundances that range from ∼ a few to 15% depending on the maximum level of nuclear activity achieved, the higher the bolometric luminosity, the lower the fraction. At the same time, we show that these probabilities are reduced by about an order of magnitude when they are filtered with the typical constraints applied by observational studies of the DAGN fraction at low redshift. Seen as a whole, our results prove that consideration of the most common limitations involved in the detection of close active pairs at optical wavelengths is sufficient alone to reconcile the intrinsic frequencies envisaged in a hierarchical universe with the small fractions of double-peaked narrow-line systems which are often reported at kpc-scales. [ABSTRACT FROM AUTHOR]

We present near-infrared integral field spectroscopy data obtained with Very Large Telescope/Spectrograph for INtegral Field Observations in the Near Infrared (SINFONI) of 'the Teacup galaxy'. The nuclear K-band (1.95-2.45 μm) spectrum of this radio-quiet type-2 quasar reveals a blueshifted broad component of FWHM ~ 1600-1800 km s-1 in the hydrogen recombination lines (Pa α, Br δ and Br γ ) and also in the coronal line [Si VI] λ1.963 μm. Thus, the data confirm the presence of the nuclear ionized outflow previously detected in the optical range and reveal its coronal counterpart. Both the ionized and coronal nuclear outflows are resolved, with seeing-deconvolved full widths at half-maximum of 1.1±0.1 and 0.9±0.1 kpc along position angle (PA) ~ 72°-74°. This orientation is almost coincident with the radio axis (PA = 77°), suggesting that the radio jet could have triggered the nuclear outflow. In the case of the H2 lines, we do not require a broad component to reproduce the profiles, but the narrow lines are blueshifted by ~50 km s-1 on average from the galaxy systemic velocity. This could be an indication of the presence of a nuclear molecular outflow, although the bulk of the H2 emission in the inner ~2 arcsec (~3 kpc) of the galaxy follows a rotation pattern. We find evidence for kinematically disrupted gas (FWHM > 250 km s-1) at up to 5.6 kpc from the AGN, which can be naturally explained by the action of the outflow. The narrow component of [Si VI] is redshifted with respect to the systemic velocity, unlike any other emission line in the K-band spectrum. This indicates that the region where the coronal lines are produced is not cospatial with the narrow-line region. [ABSTRACT FROM AUTHOR]

We use new X-ray data obtained with the Nuclear Spectroscopic Telescope Array (NuSTAR), near-infrared (NIR) fluxes and mid-infrared (MIR) spectra of a sample of 24 unobscured type 1 active galactic nuclei (AGN) to study the correlation between various hard X-ray bands between 3 and 80 keV and the infrared (IR) emission. The IR to X-ray correlation spectrum (IRXCS) shows a maximum at ∼15–20 μm, coincident with the peak of the AGN contribution to the MIR spectra of the majority of the sample. There is also an NIR correlation peak at ∼2 μm, which we associate with the NIR bump observed in some type 1 AGN at ∼1–5 μm and is likely produced by nuclear hot dust emission. The IRXCS shows practically the same behaviour in all the X-ray bands considered, indicating a common origin for all of them. We finally evaluated correlations between the X-ray luminosities and various MIR emission lines. All the lines show a good correlation with the hard X-rays (ρ ≥ 0.7), but we do not find the expected correlation between their ionization potentials and the strength of the IRXCS. [ABSTRACT FROM AUTHOR]

The discovery of γ -ray emission from radio-loud narrow-line Seyfert 1 (NLSy1) galaxies has questioned the need for large black hole masses (≳108M☉) to launch relativistic jets. We present near-infrared data of the γ -ray-emitting NLSy1 FBQS J1644+2619 that were collected using the camera CIRCE (Canarias InfraRed Camera Experiment) at the 10.4-m Gran Telescopio Canarias to investigate the structural properties of its host galaxy and to infer the black hole mass. The 2D surface brightness profile is modelled by the combination of a nuclear and a bulge component with a Sérsic profile with index n = 3.7, indicative of an elliptical galaxy. The structural parameters of the host are consistent with the correlations of effective radius and surface brightness against absolute magnitude measured for elliptical galaxies. From the bulge luminosity, we estimated a black hole mass of (2.1 ± 0.2) × 108 M☉, consistent with the values characterizing radio-loud active galactic nuclei. [ABSTRACT FROM AUTHOR]

We present subarcsecond resolution mid-infrared (MIR) images obtained with 8-10 m-class ground-based telescopes of a complete volume-limited (DL < 40 Mpc) sample of 24 Seyfert galaxies selected from the Swift/Burst Alert Telescope nine month catalogue. We use those MIR images to study the nuclear and circumnuclear emission of the galaxies. Using different methods to classify the MIR morphologies on scales of ~400 pc, we find that the majority of the galaxies (75-83 per cent) are extended or possibly extended and 17-25 per cent are pointlike. This extended emission is compact and it has low surface brightness compared with the nuclear emission, and it represents, on average, ~30 per cent of the total MIR emission of the galaxies in the sample. We find that the galaxies whose circumnuclear MIR emission is dominated by star formation (SF) show more extended emission (650 ± 700 pc) than active galactic nuclei (AGN)-dominated systems (300 ± 100 pc). In general, the galaxies with pointlike MIR morphologies are face-on or moderately inclined (b/a ~ 0.4-1.0), and we do not find significant differences between the morphologies of Sy1 and Sy2. We used the nuclear and circumnuclear fluxes to investigate their correlation with different AGN and SF activity indicators. We find that the nuclear MIR emission (the inner ~70 pc) is strongly correlated with the X-ray emission (the harder the X-rays the better the correlation) and with the [O IV] ?25.89 µm emission line, indicating that it is AGN-dominated. We find the same results, although with more scatter, for the circumnuclear emission, which indicates that the AGN dominates the MIR emission in the inner ~400 pc of the galaxies, with some contribution from SF. [ABSTRACT FROM AUTHOR]

We present 31.5 µm imaging photometry of 11 nearby Seyfert galaxies observed from the Stratospheric Observatory For Infrared Astronomy (SOFIA) using the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST). We tentatively detect extended 31 µm emission for the first time in our sample. In combination with this new data set, subarcsecond resolution 1-18 µm imaging and 7.5-13 µm spectroscopic observations were used to compute the nuclear spectral energy distribution (SED) of each galaxy.We found that the turnover of the torus emission does not occur at wavelengths ≤31.5 µm, which we interpret as a lower-limit for the wavelength of peak emission. We used CLUMPY torus models to fit the nuclear infrared (IR) SED and infer trends in the physical parameters of the AGN torus for the galaxies in the sample. Including the 31.5 µm nuclear flux in the SED (1) reduces the number of clumpy torus models compatible with the data, and (2) modifies the model output for the outer radial extent of the torus for 10 of the 11 objects. Specifically, six (60 per cent) objects show a decrease in radial extent while four (40 per cent) show an increase.We find torus outer radii ranging from <1 to 8.4 pc. [ABSTRACT FROM AUTHOR]

The origin of the unification model for Active Galactic Nuclei (AGN) was the detection of broad hydrogen recombination lines in the optical polarized spectrum of the Seyfert 2 galaxy (Sy2) NGC 1068. Since then, a search for the hidden broad-line region (HBLR) of nearby Sy2s started, but polarized broad lines have only been detected in ~30-40% of the nearby Sy2s observed to date. Here we present new VLT/FORS2 optical spectropolarimetry of a sample of 15 Sy2s, including Compton-thin and Compton-thick sources. The sample includes six galaxies without previously published spectropolarimetry, some of them normally treated as non-hidden BLR (NHBLR) objects in the literature, four classified as NHBLR, and five as HBLR based on previous data. We report ≥4σ detections of a HBLR in 11 of these galaxies (73% of the sample) and a tentative detection in NGC 5793, which is Compton-thick according to the analysis of X-ray data performed here. Our results confirm that at least some NHBLRs are misclassified, bringing previous publications reporting differences between HBLR and NHBLR objects into question. We detect broad Ha and Hβ components in polarized light for 10 targets, and just broad Hα for NGC 5793 and NGC 6300, with line widths ranging between 2100 and 9600 km s-1. High bolometric luminosities and low column densities are associated with higher polarization degrees, but not necessarily with the detection of the scattered broad components. [ABSTRACT FROM AUTHOR]

We present optical imaging and long slit spectroscopic observations of nine luminous type 2 active galactic nuclei (AGN) within the redshift range 0.3

We present new mid-infrared (mid-IR) N-band spectroscopy and Q-band photometry of the local luminous IR galaxy NGC 1614, one of the most extreme nearby starbursts. We analyse the mid-IR properties of the nucleus (central 150 pc) and four regions of the bright circumnuclear (diameter~600 pc) star-forming (SF) ring of this object. The nucleus differs from the circumnuclear SF ring by having a strong 8-12 µm continuum (low 11.3 µm PAH equivalent width). These characteristics, together with the nuclear X-ray and sub-mm properties, can be explained by an X-ray weak active galactic nucleus (AGN), or by peculiar SF with a short molecular gas depletion time and producing an enhanced radiation field density. In either case, the nuclear luminosity (LIR < 6 × 1043 erg s-1) is only <5 per cent of the total bolometric luminosity of NGC 1614. So this possible AGN does not dominate the energy output in this object. We also compare three star formation rate (SFR) tracers (Pa α, 11.3 µm PAH, and 24 µm emissions) at 150 pc scales in the circumnuclear ring. In general, we find that the SFR is underestimated (overestimated) by a factor of 2-4 (2-3) using the 11.3 µm PAH (24 µm) emission with respect to the extinction corrected Pa a SFR. The former can be explained because we do not include diffuse polycyclic aromatic hydrocarbon (PAH) emission in our measurements, while the latter might indicate that the dust temperature is particularly warmer in the central regions of NGC 1614. [ABSTRACT FROM AUTHOR]

Context. Most of the optically classified low-ionisation, narrow emission-line regions (LINERs) nuclei host an active galactic nucleus (AGN). However, how they fit into the unified model (UM) of AGN is still an open question. Aims. The aims of this work are to study at mid-infrared (mid-IR) (1) the Compton-thick nature of LINERs (i.e. hydrogen column densities of NH> 1.5 × 1024 cm-2) and (2) the disappearance of the dusty torus in LINERs predicted from theoretical arguments. Methods. We have compiled all the available low spectral-resolution, mid-IR spectra of LINERs from the InfraRed Spectrograph (IRS) onboard Spitzer. The sample contains 40 LINERs. We have complemented the LINER sample with Spitzer/IRS spectra of PGQSOs, Type-1 Seyferts (S1s), Type-2 Seyferts (S2s), and StarBurst (SB) nuclei. We studied the AGN compared to the starburst content in our sample using different indicators: the equivalent width of the polycyclic aromatic hydrocarbon at 6.2 µm, the strength of the silicate feature at 9.7 µm, and the steepness of the mid-IR spectra. We classified the spectra as SB-dominated and AGN-dominated, according to these diagnostics and compared the average mid-IR spectra of the various classes. Moreover, we studied the correlation between the 12 µm luminosity, vLv(12 µm), and the 2-10 keV energy band X-ray luminosity, LX(2-10 keV). Results. In 25 out of the 40 LINERs (i.e. 62.5%), the mid-IR spectra are not SB-dominated, similar to the comparison S2 sample (67.7%). The average spectra of both SB-dominated LINERs and S2s are very similar to the average spectrum of the SB class. The average spectrum of AGN-dominated LINERs is different from the average spectra of the other optical classes, showing a rather flat spectrum at 6-28 µm. We find that the average spectrum of AGN-dominated LINERs with X-ray luminosities LX(2-10 keV) > 1041 erg/s is similar to the average mid-IR spectrum of AGN-dominated S2s. However, faint LINERs (i.e. LX(2-10 keV) < 1041 erg/s) show flat spectra different from any of the other optical classes. The correlation between vLv(12 µm) and LX(2-10 keV) for AGN nicely extends towards low luminosities only if SB-dominated LINERs are excluded and if the 2-10 keV band X-ray luminosity is corrected in Compton-thick LINER candidates. Conclusions. We find that LINERs proposed as Compton-thick candidates at X-ray wavelengths may be confirmed according to the X-ray to mid-IR luminosity relation. We show evidence that the dusty-torus disappear when their bolometric luminosity is below Lbol ≃ 1042 erg/s. We suggest that the dominant emission at mid-IR of faint LINERs might be a combination of an elliptical galaxy host (characterised by the lack of gas), a starburst, a jet, and/or ADAF emission. Alternatively, the mid-IR emission of some of these faint LINERs could be a combination of elliptical galaxy plus carbon-rich planetary nebulae. To reconcile the Compton-thick nature of a large number of LINERs without dusty-torus signatures, we suggest that the material producing the Compton-thick X-ray obscuration is free of dust. [ABSTRACT FROM AUTHOR]

We present mid-infrared (MIR) imaging and spectroscopic data of the Seyfert 2 galaxy Mrk 1066 obtained with CanariCam (CC) on the 10.4-m Gran Telescopio CANARIAS (GTC). The galaxy was observed in imaging mode with an angular resolution of 0.24 arcsec (54 pc) in the Si-2 filter (8.7 μm). The image reveals a series of star-forming knots within the central ∼400 pc, after subtracting the dominant active galactic nucleus (AGN) component. We also subtracted this AGN unresolved component from the 8-13 μm spectra of the knots and the nucleus, and measured equivalent widths (EWs) of the 11.3 μm polycyclic aromatic hydrocarbon (PAH) feature which are typical of pure starburst galaxies. This EW is larger in the nucleus than in the knots, confirming that, at least in the case of Mrk 1066, the AGN dilutes, rather than destroys, the molecules responsible for the 11.3 μm PAH emission. By comparing the nuclear GTC/CC spectrum with the Spitzer/Infrared Spectrograph (IRS) spectrum of the galaxy, we find that the AGN component that dominates the continuum emission at λ < 15 μm on scales of ∼60 pc (90-100 per cent) decreases to 35-50 per cent when the emission of the central ∼830 pc is considered. On the other hand, the AGN contribution dominates the 15-25 μm emission (75 per cent) on the scales probed by Spitzer/IRS. We reproduced the nuclear infrared emission of the galaxy with clumpy torus models, and derived a torus gas mass of 2 × 105 M⊙, contained in a clumpy structure of ∼2 pc radius and with a column density compatible with Mrk 1066 being a Compton-thick candidate, in agreement with X-ray observations. We find a good match between the MIR morphology of Mrk 1066 and the extended Paβ, Brγ and [O III] λ5007 emission. This coincidence implies that the 8.7 μm emission is probing star formation, dust in the narrow-line region and the oval structure previously detected in the near-infrared. On the other hand, the Chandra soft X-ray morphology does not match any of the previous, contrary to what it is generally assumed for Seyfert galaxies. A thermal origin for the soft X-ray emission, rather than AGN photoionization, is suggested by the different data analysed here. [ABSTRACT FROM AUTHOR]

We present near-infrared (NIR) spectroscopic observations of 28 X-ray and mid-infrared selected sources at a median redshift of z ∼ 0.8 in the Extended Groth Strip (EGS). To date this is the largest compilation of NIR spectra of active galactic nuclei (AGN) at this redshift. The data were obtained using the multi-object spectroscopic mode of the Long-slit Intermediate Resolution Infrared Spectrograph (LIRIS) at the 4.2 m William Herschel Telescope (WHT). These galaxies are representative of a larger sample studied in a previous work, consisting of over a hundred X-ray selected sources with mid-infrared counterparts, which were classified either as AGN dominated or host galaxy dominated, depending on the shape of their spectral energy distributions (SEDs). Here, we present new NIR spectra of 13 and 15 sources of each class, respectively. We detect the Hα line at ≥1.5σ above the continuum for the majority of the galaxies. Using attenuation-corrected Hα luminosities and observed Spitzer/MIPS 24 μm fluxes, and after subtracting an AGN component estimated using an AGN empirical correlation and multifrequency SED fits, we obtain average star formation rates (SFRs) of 7 ± 7 and 20 ± 50 M⊙ yr−1, respectively (median SFRs = 7 and 5 M⊙ yr−1). These values are lower than the SFRs reported in the literature for different samples of non-active star-forming galaxies of similar stellar masses and redshifts (M* ∼ 1011 M⊙ and z ∼ 1). In spite of the small size of the sample studied here, as well as the uncertainty affecting the AGN-corrected SFRs, we speculate with the possibility of AGN quenching the star formation in galaxies at z ∼ 0.8. Alternatively, we might be seeing a delay between the offset of the star formation and AGN activity, as observed in the local Universe. [ABSTRACT FROM AUTHOR]

Recent success in explaining several properties of the dusty torus around the central engine of active galactic nuclei has been gathered with the assumption of clumpiness. The properties of such clumpy dusty tori can be inferred by analysing spectral energy distributions (SEDs), sometimes with scarce sampling given that large aperture telescopes and long integration times are needed to get good spatial resolution and signal. We aim at using the information already present in the data and the assumption of clumpy dusty torus, in particular, the CLUMPY models of Nenkova et al., to evaluate the optimum next observation such that we maximize the constraining power of the new observed photometric point. To this end, we use the existing and barely applied idea of Bayesian adaptive exploration, a mixture of Bayesian inference, prediction and decision theories. The result is that the new photometric filter we use is the one that maximizes the expected utility, which we approximate with the entropy of the predictive distribution. In other words, we have to sample where there is larger variability in the SEDs compatible with the data with what we know of the model parameters. We show that Bayesian adaptive exploration can be used to suggest new observations, and ultimately optimal filter sets, to better constrain the parameters of the clumpy dusty torus models. In general, we find that the region between 10 and 200 µm produces the largest increase in the expected utility, although sub-mm data from Atacama Large Millimeter Array also prove to be useful. It is important to note that here we are not considering the angular resolution of the data, which is key when constraining torus parameters. Therefore, the expected utilities derived from this methodology must be weighted with the spatial resolution of the data. [ABSTRACT FROM AUTHOR]

ABSTRACT We present deep Gemini Multi-Object Spectrograph-South optical broad-band images for a complete sample of 20 Sloan Digital Sky Survey selected type II quasars taken from Zakamska et al., with redshifts in the range 0.3 < z < 0.41 and [O iii]λ5007 emission-line luminosities [ABSTRACT FROM AUTHOR]

ABSTRACT We present new far-infrared (70-500 μm) Herschel Photodetector Array Camera and Spectrometer (PACS) and Spectral and Photometric Imaging Receiver (SPIRE) imaging observations as well as new mid-IR Gemini/Thermal-Region Camera Spectrograph imaging (8.7 and 18.3 μm) and spectroscopy of the inner Lindblad resonance (ILR) region ( R < 2.5 kpc) of the spiral galaxy NGC 1365. We complemented these observations with archival Spitzer imaging and spectral mapping observations. The ILR region of NGC 1365 contains a Seyfert 1.5 nucleus and a ring of star formation with an approximate diameter of 2 kpc. The strong star formation activity in the ring is resolved by the Herschel/PACS imaging data, as well as by the Spitzer 24 μm continuum emission, [Ne ii] 12.81 μm line emission, and 6.2 and 11.3 μm PAH emission. The active galactic nucleus (AGN) is the brightest source in the central regions up to λ ∼ 24 μm, but it becomes increasingly fainter in the far-infrared when compared to the emission originating in the infrared clusters (or groups of them) located in the ring. We modelled the AGN unresolved infrared emission with the clumpy torus models and estimated that the AGN contributes only to a small fraction (∼5 per cent) of the infrared emission produced in the inner ∼5 kpc. We fitted the non-AGN 24-500 μm spectral energy distribution of the ILR region and found that the dust temperatures and mass are similar to those of other nuclear and circumnuclear starburst regions. Finally we showed that within the ILR region of NGC 1365, most of the ongoing star formation activity is taking place in dusty regions as probed by the 24 μm emission. [ABSTRACT FROM AUTHOR]

ABSTRACT Mrk 938 is a luminous infrared (IR) galaxy in the local Universe believed to be the remnant of a galaxy merger. It shows a Seyfert 2 nucleus and intense star formation according to optical spectroscopic observations. We have studied this galaxy using new Herschel far-IR imaging data in addition to archival X-ray, UV, optical, near-IR and mid-IR data. Mid- and far-IR data are crucial to characterize the starburst contribution, allowing us to shed new light on its nature and to study the coexistence of active galactic nuclei (AGN) and starburst activity in the local Universe. The decomposition of the mid-IR Spitzer spectrum shows that the AGN bolometric contribution to the mid-IR and total IR luminosity is small [], which agrees with previous estimations. We have characterized the physical nature of its strong IR emission and constrained it to a relatively compact emitting region of ≤2 kpc. It is in this obscured region where most of the current star formation activity is taking place as expected for luminous IR galaxies. We have used Herschel imaging data for the first time to constrain the cold dust emission with unprecedented accuracy. We have fitted the integrated far-IR spectral energy distribution and derived the properties of the dust, obtaining a dust mass of 3 × 107 M⊙. The far-IR is dominated by emission at 35 K, consistent with dust heated by the ongoing star formation activity. [ABSTRACT FROM AUTHOR]

We present subarcsecond resolution mid-infrared (mid-IR) photometry in the range from 8 to 20 μm of 18 nearby Seyfert galaxies, reporting high spatial resolution nuclear fluxes for the entire sample (see Table 3 of Ramos Almeida et al. 2009). We construct spectral energy distributions (SEDs) that the AGN dominates, relatively uncontaminated by starlight, adding near-IR measurements from the literature at similar angular resolution. We find that the IR SEDs of intermediate-type Seyferts are flatter and present higher 10 to 18 μm ratios than those of Seyfert 2 (Sy2) galaxies. [ABSTRACT FROM PUBLISHER]

ABSTRACT Mrk 938 is a luminous infrared (IR) galaxy in the local Universe believed to be the remnant of a galaxy merger. It shows a Seyfert 2 nucleus and intense star formation according to optical spectroscopic observations. We have studied this galaxy using new Herschel far-IR imaging data in addition to archival X-ray, UV, optical, near-IR and mid-IR data. Mid- and far-IR data are crucial to characterize the starburst contribution, allowing us to shed new light on its nature and to study the coexistence of active galactic nuclei (AGN) and starburst activity in the local Universe. The decomposition of the mid-IR Spitzer spectrum shows that the AGN bolometric contribution to the mid-IR and total IR luminosity is small [], which agrees with previous estimations. We have characterized the physical nature of its strong IR emission and constrained it to a relatively compact emitting region of ≤2 kpc. It is in this obscured region where most of the current star formation activity is taking place as expected for luminous IR galaxies. We have used Herschel imaging data for the first time to constrain the cold dust emission with unprecedented accuracy. We have fitted the integrated far-IR spectral energy distribution and derived the properties of the dust, obtaining a dust mass of 3 × 107 M⊙. The far-IR is dominated by emission at 35 K, consistent with dust heated by the ongoing star formation activity. [ABSTRACT FROM AUTHOR]