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We study the ionized gas kinematics of 293 Active Galactic Nucleus (AGN) hosts as compared to that of 485 control galaxies from the MaNGA–SDSS survey using measurements of the [O  iii ] |$\lambda$| 5007 Å emission-line profiles, presenting flux, velocity, and W |$_{80}$| maps. In 45 per cent of the AGN, a broad component was needed to fit the line profiles wings within the inner few kpc, that we have identified with an outflow. But in most AGN, the profiles are broader than that of their controls over a much more extended region, identified as the 'kinematically disturbed regions' (KDRs). We find a positive correlation between the mean |$\langle$| W |$_{80}\rangle$| and L[O  iii ], supporting that the KDR is due to heating and turbulence of the ISM by outflows and radiation from the AGN. The extent R |$_{KDR}$| reaches up to 24 kpc, with a mean ratio to that of the ENLR of 57 per cent. We estimate ionized gas mass flow rates (⁠|$\dot{M}_{\rm out}$|⁠) and kinetic powers (⁠|$\dot{E}_{\rm out}$|⁠) both from the AGN broad components and from the W |$_{80}$| values, that can be obtained for the whole AGN sample. We find values for |$\dot{M}_{\rm out}$| and |$\dot{E}_{\rm out}$| that correlate with the AGN luminosity |$L_{\mathrm{ bol}}$|⁠ , populating the low-luminosity end of these known correlations. The mean coupling efficiency between |$\dot{E}_{\rm out}$| and AGN luminosity is |$\approx$| 0.02 per cent from the W |$_{80}$| values and lower from the broad component. But the large extent of the KDR shows that even low-luminosity AGN can impact the host galaxy along several kpc in a "maintenance mode" feedback. [ABSTRACT FROM AUTHOR]

We present the hot molecular and warm ionized gas kinematics for 33 nearby (0.001 ≲ z ≲ 0.056) X-ray selected active galaxies using the H |$_2\, 2.1218\, \mu$| m and Br γ emission lines observed in the K band with the Gemini near-infrared integral field spectrograph. The observations cover the inner 0.04–2 kpc of each active galactic nucleus at spatial resolutions of 4–250 pc with a velocity resolution of σinst ≈ 20  |${\rm km\, s^{-1}}$|⁠. We find that 31 objects (94 per cent) present a kinematically disturbed region (KDR) seen in ionized gas, while such regions are observed in hot molecular gas for 25 galaxies (76 per cent). We interpret the KDR as being due to outflows with masses of 102–107 and 100–104 M⊙ for the ionized and hot molecular gas, respectively. The ranges of mass-outflow rates (⁠|$\dot{M}_{\rm out}$|⁠) and kinetic power (⁠|$\dot{E}_{\rm K}$|⁠) of the outflows are 10−3–101 M⊙ yr−1 and ∼1037–1043 erg s−1 for the ionized gas outflows, and 10−5–10−2 M⊙ yr−1 and 1035–1039 erg s−1 for the hot molecular gas outflows. The median coupling efficiency in our sample is |$\dot{E}_{\mathrm{K}}/L_{\rm bol}\approx 1.8\times 10^{-3}$| and the estimated momentum fluxes of the outflows suggest they are produced by radiation-pressure in low-density environment, with possible contribution from shocks. [ABSTRACT FROM AUTHOR]

We analyse optical data cubes of the inner kiloparsec of 30 local (z ≤ 0.02) active galactic nucleus (AGN) hosts that our research group, AGNIFS, has collected over the past decade via observations with the integral field units of the Gemini Multi-Object Spectrographs. Spatial resolutions range between 50 and 300 pc and spectral coverage is from 4800 or 5600 to 7000 Å, at velocity resolutions of ≈50  |$\rm ~km~s^{-1}$|⁠. We derive maps of the gas excitation and kinematics, and determine the AGN ionization axis – which has random orientation relative to the galaxy – and the kinematic major axes of the emitting gas. We find that rotation dominates the gas kinematics in most cases, but is disturbed by the presence of inflows and outflows. Outflows have been found in 21 nuclei, usually along the ionization axis. The gas velocity dispersion is traced by W 80 (velocity width encompassing 80 per cent of the line flux), adopted as a tracer of outflows. In seven sources, W 80 is enhanced perpendicularly to the ionization axis, indicating lateral expansion of the outflow. We have estimated mass-outflow rates |$\dot{M}$| and powers |$\dot{E}$|⁠ , finding median values of |$\log \, [\dot{M}/({\rm \, M_\odot \, yr^{-1}})]=-2.1_{-1.0}^{+1.6}$| and |$\log \, [\dot{E}/({\rm \, erg\, s^{-1}})]=38.5_{-0.9}^{+1.8}$|⁠ , respectively. Both quantities show a mild correlation with the AGN luminosity (L AGN). |$\dot{E}$| is of the order of 0.01 L AGN for four sources, but much lower for the majority (nine) of the sources, with a median value of |$\log \, [\dot{E}/L_{\rm AGN} ]=-5.34_{-0.9}^{+3.2}$|⁠ , indicating that typical outflows in the local Universe are unlikely to significantly impact their host galaxy evolution. [ABSTRACT FROM AUTHOR]

In order to gauge the role that active galactic nuclei play in the evolution of galaxies via the effect of kinetic feedback in nearby QSO 2's (z ∼ 0.3), we observed eight such objects with bolometric luminosities |$L_{bol} \sim 10^{46}\rm {erg\, s^{-1}}$| using Gemini Multi-Object Spectrograph-integral field units. The emission lines were fitted with at least two Gaussian curves, the broadest of which we attributed to gas kinetically disturbed by an outflow. We found that the maximum extent of the outflow ranges from ∼1 to 8 kpc, being |${\sim }\, 0.5\, {\pm }\, 0.3$| times the extent of the [ |$\mathrm{O\,{\small III}}$| ] ionized gas region. Our ' default ' assumptions for the gas density (obtained from the [ |$\mathrm{S\,{\small II}}$| ] doublet) and outflow velocities resulted in peak mass outflow rates of |$\dot{M}_{\mathrm{ out}}^{{\tt def}}\sim$|  3–30  |$\rm {M_{\odot }}\, yr^{-1}$| and outflow power of |$\dot{E}_{\mathrm{ out}}^{{\tt \mathrm{ def}}}\sim \, 10^{41}$| – |$10^{43}\, \mathrm{erg\, s^{-1}}$|⁠. The corresponding kinetic coupling efficiencies are |$\varepsilon _f^{{\tt def}}=\dot{E}_{\mathrm{ out}}^{{\tt def}}/L_{\mathrm{ bol}}\, \sim 7\times 10^{-4}$| –0.5 per cent, with the average efficiency being only 0.06 per cent (0.01 per cent median), implying little feedback powers from ionized gas outflows in the host galaxies. We investigated the effects of varying assumptions and calculations on |$\dot{M}_{\mathrm{ out}}$| and |$\dot{E}_{\mathrm{ out}}$| regarding the ionized gas densities, velocities, masses, and inclinations of the outflow relative to the plane of the sky, resulting in average uncertainties of 1 dex. In particular, we found that better indicators of the [ |$\mathrm{O\,{\small III}}$| ] emitting gas density than the default [ |$\mathrm{S\,{\small II}}$| ] line ratio, such as the [ |$\mathrm{Ar\,{\small IV}}$| ] λλ4711,40 line ratio, result in almost an order of magnitude decrease in the ε f . [ABSTRACT FROM AUTHOR]

We present and characterize a sample of 20 nearby Seyfert galaxies selected for having BAT 14-195 keV luminosities LX ≥ 1041.5 erg s-1, redshift z ≤ 0.015, being accessible for observations with the Gemini Near-Infrared Field Spectrograph (NIFS) and showing extended [O III]λ5007 emission. Our goal is to study Active Galactic Nucleus (AGN) feeding and feedback processes from near-infrared integral-field spectra, which include both ionized (H II) and hot molecular (H2) emission. This sample is complemented by other nine Seyfert galaxies previously observed with NIFS. We show that the host galaxy properties (absolute magnitudes MB, MH, central stellar velocity dispersion and axial ratio) show a similar distribution to those of the 69 BAT AGN. For the 20 galaxies already observed, we present surface mass density (Σ) profiles for H II and H2 in their inner ˜500 pc, showing that H II emission presents a steeper radial gradient than H2. This can be attributed to the different excitation mechanisms: ionization by AGN radiation for HII and heating by X-rays for H2. The mean surface mass densities are in the range (0.2 ≤ ΣH II ≤ 35.9) Mʘ pc-2, and (0.2 ≤ ΣH2 ≤ 13.9)× 10-3 Mʘ pc-2, while the ratios between the H II and H2 masses range between ˜200 and 8000. The sample presented here will be used in future papers to map AGN gas excitation and kinematics, providing a census of the mass inflow and outflow rates and power as well as their relation with the AGN luminosity. [ABSTRACT FROM AUTHOR]

We map the kinematics of the inner (200 pc) narrow-line region (NLR) of the Seyfert 2 galaxy NGC 1068 using the instrument Near-infrared Integral Field Spectrograph and adaptive optics at the Gemini North telescope. Channel maps and position–velocity diagrams are presented at a spatial resolution of ≅8 pc and spectral resolution ∼5300 in the emission lines [Fe ii] λ1.644 μm, H2 λ2.122 μm and Brγ. The [Fe ii] emission line provides a better coverage of the NLR outflow than the previously used [O iii] λ5007 emission line, extending beyond the area of the bipolar cone observed in Brγ and [O iii]. This is mainly due to the contribution of the redshifted channels to the north-east of the nucleus, supporting its origin in a partial ionized zone with additional contribution from shocks of the outflowing gas with the galactic disc. We modelled the kinematics and geometry of the [Fe ii] emitting gas finding good agreement with the data for outflow models with conical and lemniscate (or hourglass) geometry. We calculate a mass outflow rate of $1.9^{+2}_{-1}$ M⊙ yr−1 but a power for the outflow of only 0.08 per cent LBol. The molecular (H2) gas kinematics is completely distinct from that of [Fe ii] and Brγ, showing radial expansion in an off-centred ∼100 pc radius ring in the galaxy plane. The expansion velocity decelerates from ≈200 km s−1 in the inner border of the ring to approximately zero at the outer border where our previous studies found a 10 Myr stellar population. [ABSTRACT FROM AUTHOR]

We have used the Gemini Near-infrared Integral Field Spectrograph (NIFS) to map the gas kinematics of the inner ∼200 × 500 pc2 of the Seyfert galaxy NGC 4151 in the Z, J, H and K bands at a resolving power of 5000 and spatial resolution of ∼8 pc. The ionized gas emission is most extended along the known ionization bi-cone at position angle PA = 60°–240°, but is observed also along its equatorial plane. This indicates that the active galactic nucleus (AGN) ionizes gas beyond the borders of the bi-cone, within a sphere with ≈1 arcsec radius around the nucleus. The ionized gas has three kinematic components: (1) one observed at the systemic velocity and interpreted as originating in the galactic disc; (2) one outflowing along the bi-cone, with line-of-sight velocities between −600 and 600 km s−1 and strongest emission at ±(100–300) km s−1; and (3) another component due to the interaction of the radio jet with ambient gas. The radio jet (at PA = 75°–255°) is not aligned with the narrow-line region (NLR) and produces flux enhancements mostly observed at the systemic velocity, suggesting that the jet is launched close to the plane of the galaxy (approximately plane of the sky). The mass outflow rate, estimated to be along each cone, exceeds the inferred black hole accretion rate by a factor of ∼100. This can be understood if the NLR is formed mostly by entrained gas from the circumnuclear interstellar medium by an outflow probably originating in the accretion disc. This flow represents feedback from the AGN, estimated to release a kinetic power of , which is only ∼0.3 per cent of the bolometric luminosity of the AGN. There is no evidence in our data for the gradual acceleration followed by gradual deceleration proposed by previous modelling of the [O iii] emitting gas. Our data allow the possibility that the NLR clouds are accelerated close to the nucleus (within 0.1 arcsec, which corresponds to ≈7 pc at the galaxy) after which the flow moves at essentially constant velocity (≈600 km s−1), being consistent with near-infrared emission arising predominantly from the interaction of the outflow with gas in the galactic disc. The molecular gas exhibits distinct kinematics relative to the ionized gas. Its emission arises in extended regions approximately perpendicular to the axis of the bi-cone and along the axis of the galaxy's stellar bar, avoiding the innermost ionized regions. It does not show an outflowing component, being observed only at velocities very close to systemic, and is thus consistent with an origin in the galactic plane. This hot molecular gas may only be the tracer of a larger reservoir of colder gas which represents the AGN feeding. [ABSTRACT FROM AUTHOR]

We study the nature of the extended near-UV emission in the inner kiloparsec of a sample of 15 Seyfert (Sy) galaxies which have both near-UV (F330W) and narrow-band [O iii] high-resolution Hubble images. For the majority of the objects, we find a very similar morphology in both bands. From the [O iii] images, we construct synthetic images of the nebular continuum plus the emission-line contribution expected through the F330W filter, which can be subtracted from the F330W images. We find that the emission of the ionized gas dominates the near-UV extended emission in half of the objects. A further broad-band photometric study, in the bands F330W ( U), F547M ( V) and F160W ( H), shows that the remaining emission is dominated by the underlying galactic bulge contribution. We also find a blue component whose nature is not clear in four out of 15 objects. This component may be attributed to scattered light from the active galactic nuclei, to a young stellar population in unresolved star clusters, or to early disrupted clusters. Star-forming regions and/or bright off nuclear star clusters are observed in 4/15 galaxies of the sample. [ABSTRACT FROM AUTHOR]

We present two-dimensional (2D) mapping of the gas velocity field of the inner few hundred parsecs of six nearby active galaxies, using spectra obtained with the integral field unit of the Gemini Multi-Object Spectrograph instrument at the Gemini North telescope. In our previous paper, we reported the 2D mapping of the stellar kinematics extracted from the calcium triplet absorption lines. In this paper, we use the [S iii]λ9069 emission line to obtain the flux distribution and kinematics of the gas in the narrow-line region (NLR). The gas emission is extended by a few hundred parsecs and its kinematics are dominated by rotation in the galaxy plane. Subtraction of the rotation component reveals outflows along the NLR which show spatial correlation with radio structures seen in Very Large Array radio 3.6 and 20 cm flux images, suggesting that the radio jet is pushing the circumnuclear interstellar medium. This interpretation is also supported by the observation of high-velocity dispersion structures in association with the outflowing gas. The gas outflows and radio jets are oriented at random angles relative to the galaxy major axis, indicating that they are not launched perpendicularly to the galaxy plane. Slicing the emission-line profiles into velocity channels, we create maps of the NLR gas distribution at different radial velocities. In at least half of our sample, the highest velocities are observed close to the nucleus suggesting that the emitting gas is decelerating outwards, from projected blueshifts exceeding 400 km s−1 to values of 100–200 km s−1 at 100–200 pc from the nucleus. We have estimated mass outflow rates in the NLR of ≈1 to , which are ≈10–20 times the accretion rate necessary to feed the active nucleus. The kinetic energy of the ouflow is estimated to be 4–5 orders of magnitude smaller than the bolometric luminosity. Assuming kinetic energy transfer between the radio jet and the NLR outflows, the mass ejection rate in the radio jet is 5–6 orders of magnitude smaller than the mass accretion rate necessary to feed the nuclear supermassive black hole. [ABSTRACT FROM AUTHOR]

We have used the Gemini Near-infrared Integral Field Spectrograph (NIFS) to map the emission-line intensity distributions and ratios in the narrow-line region (NLR) of the Seyfert galaxy NGC 4151 in the Z, J, H and K bands at a resolving power ≥5000, covering the inner of the galaxy at a spatial resolution of ≈8 pc. We present intensity distributions in 14 emission lines, which show three distinct behaviours. (1) Most of the ionized gas intensity distributions are extended to ≈100 pc from the nucleus along the region covered by the known biconical outflow (position angle, PA = 60/240°, NE–SW), consistent with an origin in the outflow; while the recombination lines show intensity profiles which decrease with distance r from the nucleus as , most of the forbidden lines present a flat intensity profile or even increasing with distance from the nucleus towards the border of the NLR. (2) The H2 emission lines show completely distinct intensity distributions, which avoid the region of the bicone, extending from ≈10 to ≈60 pc from the nucleus approximately along the large-scale bar, almost perpendicular to the bicone axis. This morphology supports an origin for the H2-emitting gas in the galaxy plane. (3) The coronal lines show a steep intensity profile, described by ; the emission is clearly resolved only in the case of [Si vii], consistent with an origin in the inner NLR. Using the line-ratio maps [Fe ii] 1.644/1.257 and Pa β/Br γ, we obtain an average reddening of along the NLR and at the nucleus. Our line-ratio map [Fe ii] 1.257 μm/[P ii] 1.189 μm of the NLR of NGC 4151 is the first such map of an extragalactic source. Together with the [Fe ii]/Paβ map, these line ratios correlate with the radio intensity distribution, mapping the effects of shocks produced by the radio jet on the NLR. These shocks probably release the Fe locked in grains and produce an enhancement of the [Fe ii] emission at ≈1 arcsec from the nucleus. At these regions, we obtain electron densities and temperatures for the [Fe ii]-emitting gas. For the H2-emitting gas, we obtain much lower temperatures of and conclude that the gas is in thermal equilibrium. The heating necessary to excite the molecule may be due to X-rays escaping perpendicular to the cone (through the nuclear torus, if there is one) or to shocks probably produced by the accretion flow previously observed along the large-scale bar. The distinct intensity distributions and physical properties of the ionized and molecular gas, as well as their locations, the former along the outflowing cone, and the latter in the galaxy plane surrounding the nucleus, suggest that the H2-emitting gas traces the active galactic nuclei feeding, while the ionized gas traces its feedback. [ABSTRACT FROM AUTHOR]

We present 2D mapping of the stellar velocity field within the inner 5 arcsec of six nearby active galaxies, using spectra obtained with the Integral Field Unit (IFU) of the Gemini Multi-Object Spectrograph instrument at the Gemini North telescope. The sampling of the observations is 0.2 arcsec, corresponding at the galaxies to spatial extents ranging from 10 to 30 pc. The spatial resolution range from 20 to about 180 pc, and the observed field of view covers a few hundred parsecs around the nuclei. The Ca ii triplet absorption features at ≈8500 Å were used to measure the stellar radial velocities and velocity dispersions. The radial velocity fields are dominated by rotation in all galaxies. A simple kinematical model assuming a purely rotating system with circular orbits in a plane was fitted to the radial velocity data. The turnover of the rotation curve is at only ≈50 pc for NGC 4051 and between 200 and 700 pc for the other five galaxies. The velocity dispersion (σ) maps show the largest values at the centre. In the cases of NGC 2273 and 3227, there is a decrease to at from the nucleus, delineating partial rings of low-σ values. A similar broken ring seems to be present at ≈400 pc from the nucleus also in NGC 4593. We interpret these low-σ rings as traces of recently formed stars that partially keep the cold kinematics of the original gas from which they have formed. In NGC 3516 there is a decrease of σ outwards with the steepest gradient observed along the direction of the galaxy major axis, where σ reaches ≈80–90 km s−1 at ≈400 pc from the nucleus. The main novelty of the present work is the unprecedented spatial resolution reached by a 2D study of stellar kinematics of Seyfert galaxies using an IFU. The few similar IFU studies available in the literature for Seyfert galaxies have a much poorer spatial resolution and/or are restricted to the study of emission-line kinematics. [ABSTRACT FROM AUTHOR]

We investigate the nature of the continuum emission and stellar populations in the inner 1–3 kpc of a complete sample of 24 southern radio galaxies, and we compare the results with a control sample of 18 non-active early-type galaxies. 12 of the radio galaxies are classified as Fanaroff–Riley type I (FR I), eight as FR II and four as intermediate or undefined type (FR x). Optical long-slit spectra are used to perform spectral synthesis as a function of distance from the nucleus at an average sampling of 0.5–1.0 kpc and to quantify the relative contributions of a blue featureless continuum and stellar population components of different ages. Our main finding is a systematic difference between the stellar populations of the radio and control sample galaxies: the former have a larger contribution from an intermediate-age (1 Gyr) component, suggesting a connection between the present radio activity and a starburst which occurred ∼1 Gyr ago. In addition, we find a correlation between the contribution of the 1-Gyr component and the radio power, suggesting that more massive starbursts have led to more powerful radio emission. A similar relation is found between the radio power and the mean age of the stellar population, in the sense that stronger nuclear activity is found in younger galaxies. We also find that the stellar populations of FR I galaxies are, on average, older and more homogeneous than those of FR IIs. Significant population gradients were found in only four radio galaxies, which are also those with more than 10 per cent of their total flux at 4020 Å contributed by age components younger than 100 Myr and/or a featureless continuum (indistinguishable from a 3-Myr-old stellar population). [ABSTRACT FROM AUTHOR]

ABSTRACT We use long-slit spectroscopic optical data to derive the properties of the extended emitting gas and the nuclear luminosity of a sample of 18 Seyfert 2 galaxies. From the emission-line luminosities and ratios we derive the density, reddening and mass of the ionized gas as a function of distance up to 2–4 kpc from the nucleus. Taking into account the geometric dilution of the nuclear radiation, we derive the radial distribution of covering factors and the minimum rate of ionizing photons emitted by the nuclear source. This number is an order of magnitude larger than that obtained from the rate of ionizing photons ‘intercepted’ by the gas and measured from the Hα luminosity. A calibration is proposed to recover this number from the observed luminosity. The He iiλ4686/Hβ line ratio was used to calculate the slope of the ionizing spectral energy distribution (SED), which in combination with the number of ionizing photons allows the calculation of the hard X-ray luminosities. These luminosities are consistent with those derived from X-ray spectra in the eight cases for which such data are available and recover the intrinsic X-ray emission in Compton-thick cases. Our method can thus provide reliable estimates of the X-ray fluxes in Seyfert 2 galaxies for the cases where it is not readily available. We also use the ionizing SED and luminosity to predict the infrared luminosity under the assumption that it is dominated by reprocessed radiation from a dusty torus, and find a good agreement with the observed IRAS luminosities. [ABSTRACT FROM AUTHOR]

ABSTRACT We use high signal-to-noise ratio long-slit spectra in the λλ3600–4700 range of the 20 brightest northern Seyfert 2 galaxies to study the variation of the stellar population properties as a function of distance from the nucleus. In order to characterize the stellar population and other continuum sources (e.g. featureless continuum, FC) we have measured the equivalent width, W, of six absorption features, four continuum colours and their radial variations, and performed spectral population synthesis as a function of distance from the nucleus. About half of the sample has Ca iiK and G band W values smaller at the nucleus than at 1 kpc from it, owing to a younger population and/or FC. The stellar population synthesis shows that, while at the nucleus, 75 per cent of the galaxies present contribution >20 per cent of ages ≤100 Myr and/or of an FC, this proportion decreases to 45 per cent at 3 kpc. In particular, 55 per cent of the galaxies have a contribution >10 per cent of the 3-Myr/FC component (a degenerate component in which one cannot separate what is caused by an FC or by a 3-Myr stellar population) at the nucleus, but only 25 per cent of them have this contribution at 3 kpc. As a reference, the stellar population of 10 non-Seyfert galaxies, spanning the Hubble types of the Seyfert (from S0 to Sc) was also studied. A comparison between the stellar population of the Seyferts and that of the non-Seyferts shows systematic differences: the contribution of ages younger than 1 Gyr is in most cases larger in the Seyfert galaxies than in non-Seyferts, not only at the nucleus but up to 1 kpc from it. [ABSTRACT FROM AUTHOR]

We use high signal-to-noise ratio long-slit spectra in the λλ3500–7000-Å range of three early-type (Hubble type S0) normal, two low-ionization nuclear emission region (LINER) and three Seyfert 2 galaxies to make a comparative study of the variation of the stellar population properties as a function of distance from the nucleus. In order to characterize the stellar population and other continuum sources (e.g. featureless continuum) we have measured equivalent widths (Ws) of six absorption features, continuum colours and their radial variations, and performed spectral population synthesis as a function of distance from the nucleus. The Ws for the normal galaxies are strongest at the nucleus and decrease outwards. The two LINER galaxies show a similar behaviour, but with the nuclear Ws in the blue (λ<4500 Å)≈10–20 per cent smaller. Both normal galaxies and LINERs present a redder nucleus than their surroundings. The three Seyfert 2 galaxies present the opposite behaviour, with most Ws in the blue being smaller at the nucleus, which is also bluer than outside. By combining the results of the present work with those of a previous study, we conclude that, in a sample of 12 Seyfert 2s of Hubble type S0, 10 (≈80 per cent) present nuclear Ws smaller than those of normal galaxies, while at ≈1 kpc from the nucleus this number decreases to 4 (≈30 per cent). Sampling regions of ≈100–200 pc, we conclude that the normal galaxies have nuclear stellar populations dominated by the components with an age of 10 Gyr and metallicity solar or above. The contribution of this component decreases, while that of 1 Gyr increases, with increasing distance from the nucleus. The LINERs present a similar behaviour but have a ≈10–20 per cent larger contribution of the 1-Gyr component at the nucleus. For the Seyfert 2 galaxies, there are additional components: in the three cases studied here, there is a significant contribution from a 100-Myr-old population at the nucleus plus featureless continuum in two cases and also of a 3-Myr-old component in Mrk463E. Outside the nucleus, the stellar population is similar to that of normal galaxies in ESO138-G1, but it has an excess of old metal-poor components in NGC7743 and of young components in Mrk463E, when compared with normal galaxies. The reddening of the continuum is lowest in the normal galaxy nuclei [E(B-V)[sub i]≈0.00] and highest in the Seyfert [E(B-V)[sub i]≈0.20] nuclei. [ABSTRACT FROM AUTHOR]

We study the gas emission of galaxies with active star formation, consisting mostly of H ii and starburst galaxies, as well as some Seyfert 2 galaxies, and determine chemical and physical parameters. The data consist of 19 high signal-to-noise ratio optical templates, a result of grouping 185 emission-line galaxy spectra. Underlying stellar population models (from Raimann et al.) were subtracted from the templates in order to isolate the pure emission component. We analyse the distribution of these improved signal-to-noise ratio emission spectra in diagnostic diagrams and find that the H ii templates show a smaller spread in log([O iii]/Hβ) values than the individual galaxies, apparently as a result of the population subtraction and a better signal-to-noise ratio. We thus suggest the template sequence as a fiducial observational locus for H ii galaxies which can be used as reference for models. The sequence of line ratios presented by the H ii galaxies in the diagram log([O iii]λ5007/Hβ) versus log([N ii]λ6584/Hα) is primarily owing to the gas metallicity, of which the log([N ii]/Hα) ratio is a direct estimator. We also study the properties of the starburst galaxies and those intermediate between H ii and starburst galaxies, which are more metal rich and sit on more massive galaxies. We discuss the present results in the frame of a recently proposed equivalent-width diagnostic diagram for emission-line galaxies (by Rola et al.) and conclude that the observed ranges in W([O ii])/W(Hβ) and W(Hβ) are mostly owing to the non-ionizing stellar population contribution. We propose that W(Hβ) be used as an estimator of this contribution to the continuum, and briefly discuss implications to the cosmological use of H ii galaxies. [ABSTRACT FROM AUTHOR]

Results from an analysis of low-resolution (R∼250) near-infrared long-slit spectra covering simultaneously the I, J, H and K bands, for a sample of 15 Seyfert galaxies and the NGC 5253 starburst nucleus, are presented. The Seyfert galaxies were selected as presenting ‘linear’ or cone-like high-excitation emission lines in the optical, most probably arising from the collimation of the radiation of the central source by a dusty molecular torus. Our goal was to look for signatures of this torus, and to investigate the gaseous distribution, excitation and reddening. The strongest emission lines detected are usually He i 1.083 μm and [S iii] λ9532, followed by Paβ. In some cases, [Fe ii] 1.26 and 1.64 μm are also seen. [Fe ii] 1.26 μm and H[sub 2] v=1-0 S(1) are detected in some of the higher resolution spectra obtained for five galaxies. The emission lines are spatially extended in most cases, and we have used the [Fe ii]/Paβ ratio as a measure of the gaseous excitation in Mrk 573, NGC 1386 and NGC 7582. Values for this ratio between 1.5 and 6 are found, suggesting excitation of [Fe ii] by X-rays or shock waves in some regions. Broad permitted lines are observed in three Seyfert 1 galaxies. Nuclear Paβ in NGC 1365 and possibly nuclear Brγ in Mrk 573 are also broad. From analysis of the spatial distribution of the continuum (J-H) and (H-K) colours derived from our spectra, we find redder colours for the nucleus than for the nearby bulge in most of the Seyfert 2s observed. Comparison with models including emission from dust and stars shows that hot (T∼1000 K) dust emission dominates the nuclear continuum in NGC 1365, NGC 2110, NGC 3281, NGC 7582 and ESO 362-G18. In NGC 1386, 5643 and 5728 the main contributor is the underlying stellar population, combined with some foreground reddening and/or cooler dust emission. In a few cases, the (J-H) colours on opposite sides of the nucleus differ by 0.3–0.8 mag, an effect that we interpret as partly resulting from differences in the local stellar population, and possibly extinction gradients. [ABSTRACT FROM AUTHOR]

We present the results of an optical spectral synthesis analysis for the nuclei of 20 Seyfert 2 and four radio galaxies, using a base of stellar population templates of different ages and metallicities and a power-law continuum. Compared with the stellar population of elliptical galaxies, we find that Seyfert 2s usually have a smaller contribution from old metal-rich stars (age 10 Gyr, Z ≥ Z[sub ⊙]), and a larger contribution from stars with ages of 100 Myr. We also find that the contributions from stars with ages ≤ 10 Myr and from a power-law continuum are small, rarely exceeding 5 per cent. These results show that the general assumption of elliptical galaxies as stellar population templates for these objects is incorrect, also implying that the excess blue continuum frequently found in their nuclear spectra is probably due to this template mismatch. We find a considerable contribution from 100-Myr-old stars (≈ 5 per cent), which can be interpreted from the point of view of models where the fuelling of the AGN is carried out by interactions/mergers. [ABSTRACT FROM AUTHOR]

We study the gas distribution and kinematics of the inner kpc of six moderately luminous (43.43 ≤ log  L bol ≤ 44.83) nearby (0.004 ≤ z ≤ 0.014) Seyfert galaxies observed with the Near-infrared Integral Field Spectrograph (NIFS) in the J (⁠|$1.25\,\mu$| m) and K (⁠|$2.2\,\mu$| m) bands. We analyse the most intense emission lines detected on these spectral wavebands: [Fe  ii ]  |$1.2570\, \mu$| m and Paβ, which trace the ionized gas in the partially and fully ionized regions, and |$\mathrm{ H}_2 \ 2.1218\, \mu$| m, which traces the hot (∼2000 K) molecular gas. The dominant kinematic component is rotation in the disc of the galaxies, except for the ionized gas in NGC 5899 that shows only weak signatures of a disc component. We find ionized gas outflow in four galaxies, while signatures of H2 outflows are seen in three galaxies. The ionized gas outflows display velocities of a few hundred km s−1, and their mass outflow rates are in the range 0.005–12.49 M⊙ yr−1. Their kinetic powers correspond to 0.005–0.7 per cent of the active galactic nuclei (AGN) bolometric luminosities. Besides rotation and outflows signatures in some cases, the H2 kinematics also reveals inflows in three galaxies. The inflow velocities are 50–80 km s−1 and the mass inflow rates are in the range 1–9 × 10−4 M⊙ yr−1 for hot molecular gas. These inflows might be only the hot skin of the total inflowing gas, which is expected to be dominated by colder gas. The mass inflow rates are lower than the current accretion rates to the AGN, and the ionized outflows are apparently disturbing the gas in the inner kpc. [ABSTRACT FROM AUTHOR]

For the first time, the sulphur abundance relative to hydrogen (S/H) in the narrow-line regions of a sample of Seyfert 2 nuclei (Sy 2s) has been derived via direct estimation of the electron temperature. Narrow emission-line intensities from the Sloan Digital Sky Survey (SDSS) Data Release 17 (DR17) [in the wavelength range 3000 < λ(Å) < 9100] and from the literature for a sample of 45 nearby (z  < 0.08) Sy 2s were considered. Our direct estimates indicate that Sy 2s have similar temperatures in the gas region where most of the |$\rm S\rm ^{+}$| ions are located in comparison with that of star-forming regions (SFs). However, Sy 2s present higher temperature values (⁠|${\sim} 10\, 000$|  K) in the region where most of the |$\rm S\rm ^{2+}$| ions are located relative to that of SFs. We derive the total sulphur abundance in the range of |$6.2 \: \lesssim 12+\log (\rm S/H) \: \lesssim \: 7.5$|⁠ , corresponding to 0.1–1.8 times the solar value. These sulphur abundance values are lower by ∼0.4 dex than those derived in SFs with similar metallicity, indicating a distinct chemical enrichment of the interstellar medium (ISM) for these object classes. The sulphur abundance relative to oxygen (S/O) values for our Sy 2 sample present an abrupt (∼0.5 dex) decrease with increasing oxygen abundance relative to hydrogen (O/H) for the high-metallicity regime [ |$\rm 12+\log (O/H) \: \gtrsim 8.7)$| ], what is not seen for the SFs. However, when our Sy 2 estimates are combined with those from a large sample of SFs, we did not find any dependence between S/O and O/H. [ABSTRACT FROM AUTHOR]

We present two-dimensional maps of emission-line fluxes and kinematics, as well as of the stellar kinematics of the central few kpc of five bright nearby Seyfert galaxies -Mrk 6, Mrk 79, Mrk 348, Mrk 607, and Mrk 1058 - obtained from observations with the Gemini Multi-Object Spectrograph Integral Field Unit on the Gemini North Telescope. The data cover the inner 3.5 arcsecx5.0 arcsec - corresponding to physical scales in the range 0.6x0.9-1.5x2.2 kpc² - at a spatial resolution ranging from 110 to 280 pc with a spectral coverage of 4300-7100Å and velocity resolution of ≈90 km s-1. The gas excitation is Seyfert like everywhere but show excitation gradients that are correlated with the gas kinematics, reddening and/or the gas density. The gas kinematics show in all cases two components: a rotation one similar to that observed in the stellar velocity field, and an outflow component. In the case of Mrk607, the gas is counter-rotating relative to the stars. Enhanced gas velocity dispersion is observed in association with the outflows according to two patterns: at the locations of the highest outflow velocities along the ionization axis or perpendicularly to it in a strip centred at the nucleus that we attribute to an equatorial outflow. Bipolar outflows are observed in Mrk 348 and Mrk 79, while in Mrk 1058 only the blueshifted part is clearly observed, while in cases of Mrk 6 and Mrk 607, the geometry of the outflow needs further constraints from modelling to be presented in a forthcoming study, where the mass flow rate and powers will also be obtained. [ABSTRACT FROM AUTHOR]

In a recently completed survey of the stellar population properties of low-ionization nuclear emission-line regions (LINERs) and LINER/H iitransition objects (TOs), we have identified a numerous class of galactic nuclei which stand out because of their conspicuous 108−9 yr populations, traced by high-order Balmer absorption lines and other stellar indices. These objects are called‘young-TOs’, because they all have TO-like emission-line ratios. In this paper we extend this previous work, which concentrated on the nuclear properties, by investigating the radial variations of spectral properties in low-luminosity active galactic nuclei (LLAGNs). Our analysis is based on high signal-to-noise ratio (S/N) long-slit spectra in the 3500–5500Å interval for a sample of 47 galaxies. The data probe distances of typically up to 850 pc from the nucleus with a resolution of∼100 pc (∼1 arcsec) and S/N∼ 30. Stellar population gradients are mapped by the radial profiles of absorption-line equivalent widths and continuum colours along the slit. These variations are further analysed by means of a decomposition of each spectrum in terms of template galaxies representative of very young (≤107 yr), intermediate age (108–9 yr) and old (1010 yr) stellar populations.This study reveals that young-TOs also differ from old-TOs and old-LINERs in terms of the spatial distributions of their stellar populations and dust. Specifically, our main findings are as follows. (i) Significant stellar population gradients are found almost exclusively in young-TOs. (ii) The intermediate age population of young-TOs, although heavily concentrated in the nucleus, reaches distances of up to a few hundred pc from the nucleus. Nevertheless, the half width at half-maximum of its brightness profile is more typically 100 pc or less. (iii) Objects with predominantly old stellar populations present spatially homogeneous spectra, be they LINERs or TOs. (iv) Young-TOs have much more dust in their central regions than other LLAGNs. (v) TheB-band luminosities of the central≲1 Gyr population in young-TOs are within an order of magnitude of, implying masses of the order of. This population was 10–100 times more luminous in its formation epoch, at which time young massive stars would have completely outshone any active nucleus, unless the AGN too was brighter in the past. [ABSTRACT FROM AUTHOR]

The merger remnant NGC 34 is a local luminous infrared galaxy (LIRG) hosting a nuclear starburst and a hard X-ray source associated with a putative, obscured Seyfert 2 nucleus. In this work, we use adaptive optics assisted near-infrared (NIR) integral field unit observations of this galaxy to map the distribution and kinematics of the ionized and molecular gas in its inner |$\mathrm{1.2\, kpc \times 1.2\, kpc}$|⁠ , with a spatial resolution of 70 pc. The molecular and ionized gas kinematics is consistent with a disc with projected major axis along a mean PA = −9 |${_{.}^{\circ}}$| 2 ± 0 |${_{.}^{\circ}}$| 9. Our main findings are that NGC 34 hosts an AGN and that the nuclear starburst is distributed in a circumnuclear star formation ring with inner and outer radii of ≈ 60 and 180 pc, respectively, as revealed by maps of the |$\mathrm{[Fe\, {\small {II}}] / Pa\,\beta }$| and H2/Br  γ emission-line ratios, and corroborated by PCA tomography analysis. The spatially resolved NIR diagnostic diagram of NGC 34 also identifies a circumnuclear structure dominated by processes related to the stellar radiation field and a nuclear region where |$[\rm Fe\, {\small {II}}]$| and H2 emissions are enhanced relative to the hydrogen recombination lines. We estimate that the nuclear X-ray source can account for the central H2 enhancement and conclude that |$[\rm Fe\, {\small {II}}]$| and H2 emissions are due to a combination of photoionization by young stars, excitation by X-rays produced by the AGN and shocks. These emission lines show nuclear, broad, blueshifted components that can be interpreted as nuclear outflows driven by the AGN. [ABSTRACT FROM AUTHOR]

We present a dynamical study of the narrow-line regions in two nearby type 2 quasars (QSO2s). We construct dynamical models based on detailed photoionization models of the emission-line gas, including the effects of internal dust, to apply to observations of large-scale outflows from these active galactic nuclei (AGNs). We use Mrk 477 and Mrk 34 in order to test our models against recent Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) observations of [O  iii ] emission-line kinematics, since these AGNs possess more energetic outflows than found in Seyfert galaxies. We find that the outflows within 500 pc are consistent with radiative acceleration of dusty gas, however the outflows in Mrk 34 are significantly more extended and may not be directly accelerated by radiation. We characterize the properties of X-ray winds found from the expansion of [O  iii ]-emitting gas close to the black hole. We show that such winds possess the kinetic energy density to disturb [O  iii ] gas at ∼1.8 kpc, and have sufficient energy to entrain the [O  iii ] clouds at ∼1.2 kpc. Assuming that the X-ray wind possesses the same radial mass distribution as the [O  iii ] gas, we find that the peak kinetic luminosity for this wind is 2 per cent of Mrk 34's bolometric luminosity, which is in the 0.5–5 per cent range required by some models for efficient feedback. Our work shows that, although the kinetic luminosity as measured from [O  iii ]-emitting gas is frequently low, X-ray winds may provide more than one order of magnitude higher kinetic power. [ABSTRACT FROM AUTHOR]

We study the stellar population of galaxies with active star formation, determining ages of the stellar components by means of spectral population synthesis of their absorption spectra. The data consist of optical spectra of 185 nearby (z&les;0.075) emission-line galaxies. They are mostly H ii galaxies, but we also include some starbursts and Seyfert 2s, for comparison purposes. They were grouped into 19 high signal-to-noise ratio template spectra, according to their continuum distribution, absorption- and emission-line characteristics. The templates were then synthesized with a star cluster spectral base. The synthesis results indicate that H ii galaxies are typically age-composite stellar systems, presenting important contributions from generations up to as old as 500 Myr. We detect a significant contribution of populations with ages older than 1 Gyr in two groups of H ii galaxies. The age distributions of stellar populations among starbursts can vary considerably despite similarities in the emission-line spectra. In the case of Seyfert 2 groups we obtain important contributions from the old population, consistent with a bulge. From the diversity of star formation histories, we conclude that typical H ii galaxies in the local Universe are not systems presently forming their first stellar generation. [ABSTRACT FROM AUTHOR]

We derive a distance of D = 16.6 ± 0.3 Mpc (μ = 31.10 ± 0.04 mag) to the archetypal narrow-line Seyfert 1 galaxy NGC 4051 based on Cepheid period–luminosity relations and new Hubble Space Telescope multiband imaging. We identify 419 Cepheid candidates and estimate the distance at both optical and near-infrared wavelengths using subsamples of precisely photometered variables (123 and 47 in the optical and near-infrared subsamples, respectively). We compare our independent photometric procedures and distance-estimation methods to those used by the Supernovae, H0, for the Equation of State team and find agreement to 0.01 mag. The distance we obtain suggests an Eddington ratio of for NGC 4051, typical of narrow-line Seyfert 1 galaxies, unlike the seemingly odd value implied by previous distance estimates. We derive a peculiar velocity of −490 ± 34 km s−1 for NGC 4051, consistent with the overall motion of the Ursa Major Cluster in which it resides. We also revisit the energetics of the NGC 4051 nucleus, including its outflow and mass accretion rates. [ABSTRACT FROM AUTHOR]

We present maps for the electron temperature in the inner kpc of three luminous Seyfert galaxies: Mrk 79, Mrk 348, and Mrk 607 obtained from Gemini Multi-Object Spectrograph-integral field unit observations at spatial resolutions of ∼110–280 pc. We study the distributions of electron temperature in active galaxies and find temperatures varying in the range from ∼8000 to |$\gtrsim 30\, 000\,$| K. Shocks due to gas outflows play an important role in the observed temperature distributions of Mrk 79 and Mrk 348, while standard photoionization models reproduce the derived temperature values for Mrk 607. In Mrk 79 and Mrk 348, we find direct evidence for shock ionization with overall orientation orthogonal to the ionization axis, where shocks can be easily observed as the active galactic nuclei radiation field is shielded by the nuclear dusty torus. This also indicates that even when the ionization cones are narrow, the shocks can be much wider angle. [ABSTRACT FROM AUTHOR]

We use Hubble Space Telescope /Space Telescope Imaging Spectrograph long-slit G430M and G750M spectra to analyse the extended [O  iii ] λ5007 emission in a sample of 12 nearby (z < 0.12) luminous (L bol > 1.6 × 1045 erg s−1) QSO2s. The purpose of the study is to determine the properties of the mass outflows of ionized gas and their role in active galactic nucleus feedback. We measure fluxes and velocities as functions of radial distances. Using cloudy models and ionizing luminosities derived from [O  iii ] λ5007, we are able to estimate the densities for the emission-line gas. From these results, we derive masses of [O  iii ]-emitting gas, mass outflow rates, kinetic energies, kinetic luminosities, momenta, and momentum flow rates as a function of radial distance for each of the targets. For the sample, masses are several times |$10^{3}$| – |$10^{7}\, {\rm M_{\odot }}$| and peak outflow rates are from 9.3 × 10−3 to |$10.3\, {\rm M_{\odot }}\, {\rm yr^{-1}}$|⁠. The peak kinetic luminosities are (3.4 × 10−8)–(4.9 × 10−4) of the bolometric luminosity, which does not approach the (5.0 × 10−3)–(5.0 × 10−2) range required by some models for efficient feedback. For Mrk 34, which has the largest kinetic luminosity of our sample, in order to produce efficient feedback there would have to be 10 times more [O  iii ]-emitting gas than that we detected at its position of maximum kinetic luminosity. Three targets show extended [O  iii ] emission, but compact outflow regions. This may be due to different mass profiles or different evolutionary histories. [ABSTRACT FROM AUTHOR]

We derive a distance of 15.8 ± 0.4 Mpc to the archetypal Seyfert 1 galaxy NGC 4151 based on the near-infrared Cepheid period–luminosity relation and new Hubble Space Telescope multiband imaging. This distance determination, based on measurements of 35 long-period (P > 25 days) Cepheids, will support the absolute calibration of the supermassive black hole mass in this system, as well as studies of the dynamics of the feedback or feeding of its active galactic nucleus. [ABSTRACT FROM AUTHOR]

We map the optical and near-infrared (NIR) emission-line flux distributions and kinematics of the inner 320 × 535 pc2 of the elliptical galaxy NGC 1052. The integral field spectra were obtained with the Gemini Telescope using the GMOS-IFU and NIFS instruments, with angular resolutions of 0.88 and 0.1 arcsec in the optical and NIR, respectively. We detect five kinematic components: (1) and (2) two spatially unresolved components: a broad-line region visible in H α, with a full width at half-maximum (FWHM) of ∼3200 km s−1, and an intermediate broad component seen in the [O  iii ] λλ4959,5007 doublet; (3) an extended intermediate-width component with 280 km s−1 < FWHM < 450 km s−1 and centroid velocities up to 400 km s−1, which dominates the flux in our data, attributed either to a bipolar outflow related to the jets, rotation in an eccentric disc or to a combination of a disc and large-scale gas bubbles; (4) and (5) two narrow (FWHM < 150 km s−1) components, one visible in [O  iii ], and another visible in the other emission lines, extending beyond the field of view of our data, which is attributed to large-scale shocks. Our results suggest that the ionization within the observed field of view cannot be explained by a single mechanism, with photoionization being the dominant mechanism in the nucleus with a combination of shocks and photoionization responsible for the extended ionization. [ABSTRACT FROM AUTHOR]

We have recently initiated the first spectroscopic dust reverberation programme on active galactic nuclei in the near-infrared. Spectroscopy enables measurement of dust properties, such as flux, temperature, and covering factor, with higher precision than photometry. In particular, it enables measurement of both luminosity-based dust radii and dust response times. Here we report results from a 1 yr campaign on NGC 5548. The hot dust responds to changes in the irradiating flux with a lag time of ∼70 light-days, similar to what was previously found in photometric reverberation campaigns. The mean and rms spectra are similar, implying that the same dust component dominates both the emission and the variations. The dust lag time is consistent with the luminosity-based dust radius only if we assume a wavelength-independent dust emissivity law, i.e. a blackbody, which is appropriate for grains of large sizes (of a few μ m). For such grains the dust temperature is ∼1450 K. Therefore, silicate grains have most likely evaporated and carbon is the main chemical component. But the hot dust is not close to its sublimation temperature, contrary to popular belief. This is further supported by our observation of temperature variations largely consistent with a heating/cooling process. Therefore, the inner dust-free region is enlarged and the dusty torus rather a 'dusty wall', whose inner radius is expected to be luminosity-invariant. The dust-destruction mechanism that enlarges the dust-free region seems to also partly affect the dusty region. We observe a cyclical decrease in dust mass with implied dust reformation times of ∼5–6 months. [ABSTRACT FROM AUTHOR]

We present a multiwavelength study of the OH megamaser galaxy IRAS17526 + 3253, based on new Gemini multi-object spectrograph integral field unit (GMOS/IFU) observations, Hubble Space Telescope F814W, and H α + [N  ii ] images, and archival 2MASS and 1.49 GHz VLA data. The Hubble Space Telescope (HST) images clearly reveal a mid-to-advanced stage major merger whose northwestern and southeastern nuclei have a projected separation of ∼8.5 kpc. Our HST /H α + [N  ii ] image shows regions of ongoing star formation across the envelope on ∼10 kpc scales, which are aligned with radio features, supporting the interpretation that the radio emission originates from star-forming regions. The measured H α luminosities imply that the unobscured star formation rate (SFR) is ∼10–30 M⊙ yr−1. The GMOS/IFU data reveal two structures in northwestern separated by 850 pc and by a discontinuity in the velocity field of ∼ 200 km s−1. We associate the blueshifted and redshifted components with, respectively, the distorted disc of northwestern and tidal debris, possibly a tail originating in southeastern. Star formation is the main ionization source in both components, which have SFRs of ∼2.6–7.9 M⊙ yr−1 and ∼1.5–4.5 M⊙ yr−1, respectively. Fainter line emission bordering these main components is consistent with shock ionization at a velocity ∼200 km s−1 and may be the result of an interaction between the tidal tail and the northwestern galaxy's disc. IRAS17526 + 3253 is one of only a few systems known to host both luminous OH and H2O masers. The velocities of the OH and H2O maser lines suggest that they are associated with the northwestern and southeastern galaxies, respectively (Martin et al.; Wagner). [ABSTRACT FROM AUTHOR]

We map optical and near-infrared (NIR) stellar population properties of the inner 320 × 535 pc2 of the elliptical galaxy NGC 1052. The optical and NIR spectra were obtained using the Gemini Integral Field Units of the GMOS instrument and NIFS, respectively. By performing stellar population synthesis in the optical alone, we find that this region of the galaxy is dominated by old (t > 10 Gyr) stellar populations. Using the NIR, we find the nucleus to be dominated by old stellar populations, and a circumnuclear ring with younger (∼2.5 Gyr) stars. We also combined the optical and NIR datacubes and performed a panchromatic spatially resolved stellar population synthesis, which resulted in a dominance of older stellar populations, in agreement with optical results. We argue that the technique of combining optical and NIR data might be useful to isolate the contribution of stellar population ages with strong NIR absorption bands. We also derive the stellar kinematics and find that the stellar motions are dominated by a high (∼240 km s−1) velocity dispersion in the nucleus, with stars also rotating around the centre. Lastly, we measure the absorption bands, both in the optical and in the NIR, and find a nuclear drop in their equivalent widths. The favoured explanation for this drop is a featureless continuum emission from the low luminosity active galactic nucleus. [ABSTRACT FROM AUTHOR]

We present a spatially resolved stellar population study of the inner ∼200 pc radius of NGC 4303 based on near-infrared integral field spectroscopy with SINFONI/VLT at a spatial resolution of 40–80 pc and using the starlight code. We found that the distribution of the stellar populations presents a spatial variation, suggesting an age stratification. Three main structures stand out. Two nuclear blobs, one composed by young stars (t ≤ 50 Myr) and one with intermediate-age stars (50 Myr < t ≤ 2 Gyr), both shifted from the centre. The third one is an internal intermediate-age spiral arm-like structure, surrounding the blob of young stars. Our results indicate that star formation has occurred through multiple bursts in this source. Furthermore, the youngest stellar populations (t ≲ 2 Gyr) are distributed along a circumnuclear star-forming ring with r ∼ 250 pc. The ring displays star formation rates (SFRs) in the range of 0.002–0.14 M⊙yr−1, favouring the 'pearls-on-a-string' scenario. The old underlying bulge stellar population component (t > 2 Gyr) is distributed outside the two blob structures. For the nuclear region (inner ∼60 pc radius) we derived an SFR of 0.43 M⊙ yr−1 and found no signatures of non-thermal featureless continuum and hot dust emission, supporting the scenario in which an LLAGN/LINER-like source is hidden in the centre of NGC 4303. Thus, our results reveal a rather complex star formation history in NGC 4303, with different stellar population components coexisting with a low efficiency accreting black hole in its centre. [ABSTRACT FROM AUTHOR]

Context. Tracing nuclear inflows and outflows in active galactic nuclei (AGNs), determining the mass of gas involved in them, and their impact on the host galaxy and nuclear black hole requires 3D imaging studies of both the ionized and molecular gas. Aims. We map the distribution and kinematics of molecular and ionized gas in a sample of active galaxies to quantify the nuclear inflows and outflows. Here, we analyze the nuclear kinematics of NGC 1566 via ALMA observations of the CO J:2-1 emission at 24 pc spatial and ∼2.6 km s−1 spectral resolution, and Gemini-GMOS/IFU observations of ionized gas emission lines and stellar absorption lines at similar spatial resolution, and 123 km s−1 of intrinsic spectral resolution. Methods. The morphology and kinematics of stellar, molecular (CO), and ionized ([N II]) emission lines are compared to the expectations from rotation, outflows, and streaming inflows. Results. While both ionized and molecular gas show rotation signatures, there are significant non-circular motions in the innermost 200 pc and along spiral arms in the central kpc (CO). The nucleus shows a double-peaked CO profile (full width at zero intensity of 200 km s−1), and prominent (∼80 km s−1) blue- and redshifted lobes are found along the minor axis in the inner arcseconds. Perturbations by the large-scale bar can qualitatively explain all features in the observed velocity field. We thus favor the presence of a molecular outflow in the disk with true velocities of ∼180 km s−1 in the nucleus and decelerating to 0 by ∼72 pc. The implied molecular outflow rate is 5.6 M⊙ yr−1, with this gas accumulating in the nuclear 2″ arms. The ionized gas kinematics support an interpretation of a similar but more spherical outflow in the inner 100 pc, with no signs of deceleration. There is some evidence of streaming inflows of ∼50 km s−1 along specific spiral arms, and the estimated molecular mass inflow rate, ∼0.1 M⊙ yr−1, is significantly higher than the SMBH accretion rate (ṁ = 4.8 × 10−5M⊙ yr−1). [ABSTRACT FROM AUTHOR]

We study the properties of 66 galaxies with kinematically misaligned gas and stars from MaNGA survey. The fraction of kinematically misaligned galaxies varies with galaxy physical parameters, i.e. M*, SFR and sSFR. According to their sSFR, we further classify these 66 galaxies into three categories, 10 star-forming, 26 ‘Green Valley’ and 30 quiescent ones. The properties of different types of kinematically misaligned galaxies are different in that the star-forming ones have positive gradient in Dn4000 and higher gas-phase metallicity, while the green valley/quiescent ones have negative Dn4000 gradients and lower gas-phase metallicity on average. There is evidence that all types of the kinematically misaligned galaxies tend to live in more isolated environment. Based on all these observational results, we propose a scenario for the formation of star-forming galaxies with kinematically misaligned gas and stars − the progenitor accretes misaligned gas from a gas-rich dwarf or cosmic web, the cancellation of angular momentum from gas–gas collisions between the pre-existing gas and the accreted gas largely accelerates gas inflow, leading to fast centrally concentrated star formation. The higher metallicity is due to enrichment from this star formation. For the kinematically misaligned green valley and quiescent galaxies, they might be formed through gas-poor progenitors accreting kinematically misaligned gas from satellites which are smaller in mass. [ABSTRACT FROM AUTHOR]

We use high-spectral resolution (R > 8000) data covering 3800–13 000 Å to study the physical conditions of the broad-line region (BLR) of nine nearby Seyfert 1 galaxies. Up to six broad H i lines are present in each spectrum. A comparison – for the first time using simultaneous optical to near-infrared observations – to photoionization calculations with our devised simple scheme yields the extinction to the BLR at the same time as determining the density and photon flux, and hence distance from the nucleus, of the emitting gas. This points to a typical density for the H i emitting gas of 1011 cm−3 and shows that a significant amount of this gas lies at regions near the dust sublimation radius, consistent with theoretical predictions. We also confirm that in many objects, the line ratios are far from case B, the best-fitting intrinsic broad-line Hα/H β ratios being in the range 2.5–6.6 as derived with our photoionization modelling scheme. The extinction to the BLR, based on independent estimates from H i and He ii lines, is AV ≤ 3 for Seyfert 1–1.5s, while Seyfert 1.8–1.9s have AV in the range 4–8. A comparison of the extinction towards the BLR and narrow-line region (NLR) indicates that the structure obscuring the BLR exists on scales smaller than the NLR. This could be the dusty torus, but dusty nuclear spirals or filaments could also be responsible. The ratios between the X-ray absorbing column NH and the extinction to the BLR are consistent with the Galactic gas-to-dust ratio if NH variations are considered. [ABSTRACT FROM AUTHOR]

In a former paper, we have presented spectra of 64 active, nine normal and five starburst galaxies in the region around the near-infrared calcium triplet (CaT) absorption lines and the [S iii]λ9069 line. In the present paper, we analyse the CaT strength ( WCaT) and kinematical products derived in that study, namely stellar and ionized gas (σgas) velocity dispersions. Our main results may be summarized as follows. (1) Type 2 Seyfert galaxies show no sign of dilution in WCaT with respect to the values spanned by normal galaxies, even when optical absorption lines such as the Ca ii K band at 3933 Å are much weaker than in old, bulge-like stellar populations. (2) The location of type 2 Seyfert galaxies in the plane is consistent with evolutionary synthesis models. The implication is that the source responsible for the dilution of optical lines in these active galactic nuclei (AGN) is a young stellar population, rather than an AGN featureless continuum, confirming the conclusion of the pioneer study of Terlevich, Díaz & Terlevich. (3) In type 1 Seyfert galaxies, both and WCaT tend to be diluted due to the presence of a non-stellar component, in agreement with the unification paradigm. (4) A comparison of with σgas (obtained from the core of the [S iii] emitting line) confirms the existence of a correlation between the typical velocities of stars and clouds of the narrow line region. The strength and scatter around this correlation are similar to those previously obtained from the [O iii]λ5007 linewidth. [ABSTRACT FROM AUTHOR]

The power of jets from black holes is expected to depend on both the spin of the black hole and the structure of the accretion disc in the region of the last stable orbit. We investigate these dependencies using two different physical models for the jet power: the classical Blandford–Znajek (BZ) model and a hybrid model developed by Meier. In the BZ case, the jets are powered by magnetic fields directly threading the spinning black hole while in the hybrid model, the jet energy is extracted from both the accretion disc as well as the black hole via magnetic fields anchored to the accretion flow inside and outside the hole's ergosphere. The hybrid model takes advantage of the strengths of both the Blandford–Payne and BZ mechanisms, while avoiding the more controversial features of the latter. We develop these models more fully to account for general relativistic effects and to focus on advection-dominated accretion flows (ADAFs) for which the jet power is expected to be a significant fraction of the accreted rest mass energy. We apply the models to elliptical galaxies, in order to see if these models can explain the observed correlation between the Bondi accretion rates and the total jet powers. For typical values of the disc viscosity parameter and mass accretion rates consistent with ADAF model expectations, we find that the observed correlation requires ; that is, it implies that the black holes are rapidly spinning. Our results suggest that the central black holes in the cores of clusters of galaxies must be rapidly rotating in order to drive jets powerful enough to heat the intracluster medium and quench cooling flows. [ABSTRACT FROM AUTHOR]

We present a spectroscopic atlas of active galactic nuclei covering the region around thecalcium triplet (CaT). The sample comprises 78 objects, divided into 43 Seyfert 2s, 26 Seyfert 1s, three starburst and six normal galaxies. The spectra pertain to the inner∼300 pc in radius, and thus sample the central kinematics and stellar populations of active galaxies. The data are used to measure stellar velocity dispersionswith both cross-correlation and direct fitting methods. These measurements are found to be in good agreement with each other and with those in previous studies for objects in common. The CaT equivalent width is also measured. We find average values and sample dispersions ofWCaT ofandfor Seyfert 1s, Seyfert 2s and normal galaxies, respectively. We further present an atlas of[S iii]λ9069 emission-line profiles for a subset of 40 galaxies. These data are analysed in a companion paper which addresses the connection between stellar and narrow-line region kinematics, the behaviour of the CaT equivalent width as a function ofσ★, activity type and stellar population properties. [ABSTRACT FROM AUTHOR]

In recent observations by the Hubble Space Telescope (HST) as part of a campaign to discover locations and kinematics of AGN outflows, we found that Mrk 509 contains a 3″ (∼2100 pc) linear filament in its central region. Visible in both optical continuum and [O III] imaging, this feature resembles a “check mark” of several knots of emission that travel northwest to southeast before jutting toward the nucleus from the southwest. Space Telescope Imaging Spectrograph (STIS/HST) observations along the inner portion of the filament reveal redshifted velocities, indicating that the filament is inflowing. We present further observations of the nucleus in Mrk 509 using the Gemini Near-Infrared Integral Field Spectrograph, from which we conclude that this structure cannot be related to previously studied, typical narrow line region outflows and instead embodies the remains of an ongoing minor merger with a gas-rich dwarf galaxy, therefore providing a great opportunity to study the fueling of an AGN by a minor merger in progress. [ABSTRACT FROM AUTHOR]