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Active galactic nucleus (AGN) driven outflows are believed to play an important role in regulating the growth of galaxies, mostly via negative feedback. However, their effects on their hosts are far from clear, especially for low- and moderate-luminosity Seyferts. To investigate this issue, we obtained cold molecular gas observations, traced by the CO(2-1) transition, using the NOEMA interferometer of five nearby (distances between 19 and 58 Mpc) Seyfert galaxies. The resolution of ∼0.3–0.8 (∼30–100 pc) and field of view of NOEMA allowed us to study the CO(2-1) morphology and kinematics in the nuclear regions (∼100 pc) and up to radial distances of ∼900 pc. We detected CO(2-1) emission in all five galaxies with disky or circumnuclear ring-like morphologies. We derived cold molecular gas masses on nuclear (∼100 pc) and circumnuclear (∼650 pc) scales in the range from 106 to 107 M⊙ and from 107 to 108 M⊙, respectively. In all of our galaxies, the bulk of this gas is rotating in the plane of the galaxy. However, noncircular motions are also present. In NGC 4253, NGC 4388, and NGC 7465, we can ascribe the streaming motions to the presence of a large-scale bar. In Mrk 1066 and NGC 4388, the noncircular motions in the nuclear regions are explained as outflowing material due to the interaction of the AGN wind with molecular gas in the galaxy disk. We conclude that for an unambiguous and precise interpretation of the kinematics of the cold molecular gas, we need detailed knowledge of the host galaxy (i.e., presence of bars, interactions, etc.), and also of the ionized gas kinematics and ionization cone geometry. [ABSTRACT FROM AUTHOR]

High-resolution observations from the submm to the optical wavelength regime resolve the central few 100 pc region of nearby galaxies in great detail. They reveal a large diversity of features: thick gas and stellar discs, nuclear starbursts, inflows and outflows, central activity, jet interaction, etc. Concentrating on the role circumnuclear discs play in the life cycles of galactic nuclei, we employ 3D adaptive mesh refinement hydrodynamical simulations with the RAMSES code to self-consistently trace the evolution from a quasi-stable gas disc, undergoing gravitational (Toomre) instability, the formation of clumps and stars and the disc's subsequent, partial dispersal via stellar feedback. Our approach builds upon the observational finding that many nearby Seyfert galaxies have undergone intense nuclear starbursts in their recent past and in many nearby sources star formation is concentrated in a handful of clumps on a few 100 pc distant from the galactic centre. We show that such observations can be understood as the result of gravitational instabilities in dense circumnuclear discs. By comparing these simulations to available integral field unit observations of a sample of nearby galactic nuclei, we find consistent gas and stellar masses, kinematics, star formation and outflow properties. Important ingredients in the simulations are the self-consistent treatment of star formation and the dynamical evolution of the stellar distribution as well as the modelling of a delay time distribution for the supernova feedback. The knowledge of the resulting simulated density structure and kinematics on pc scale is vital for understanding inflow and feedback processes towards galactic scales. [ABSTRACT FROM AUTHOR]

The active galaxy MCG-C6-30-15 has a 400 pc diameter stellar kinematically distinct core, counter-rotating with respect to the main body of the galaxy. Our previous high spatial resolution (0.1 arcsec) H-band observations of this galaxy mapped the stellar kinematics and [Fe II] 1.64 μm gas dynamics though mainly restricted to the spatial region of the counter-rotating core. In this work, we probe the stellar kinematics on a larger field of view and determine the ionized and molecular gas dynamics to study the formation of the counter-rotating core and the implications for active galactic nucleus (AGN) fuelling. We present integral field spectroscopy observations with SINFONI in the H and K bands in the central 1.2 kpc and with VIMOS HR-blue in the central 4 kpc of the galaxy. Ionized gas outflows of vout ~ 100 km s.1 are traced by the [Ca VIII] 2.32 μm coronal line and extend out to at least a radius of r ~ 140 pc. The molecular gas, traced by the H2 2.12 μm emission, is also counter-rotating with respect to the main body of the galaxy, indicating that the formation of the distinct core was associated with inflow of external gas into the centre of MCG-C6-30-15. The molecular gas traces the available gas reservoir for AGN fuelling and is detected as close as r ~ 50-C100 pc. External gas accretion is able to significantly replenish the fuelling reservoir suggesting that the event which formed the counter-rotating core was also the main mechanism providing gas for AGN fuelling. [ABSTRACT FROM AUTHOR]

In a matched sample of Seyfert and quiescent galaxies we simultaneously probe the stellar and molecular gas kinematics from 1 kpc down to 50 pc with the aim of identifying the dynamical processes dictating black hole accretion rates. This first paper compares the global characteristics of a sample of 10 galaxies. We find several differences within a radius of 500 pc that are correlated with active galactic nucleus (AGN) activity. The Seyferts have (1) a more centrally concentrated nuclear stellar surface brightness with lower stellar luminosities beyond a radius of 100 pc, (2) a lower stellar velocity dispersion within a radius of 200 pc, (3) elevated H2 1-0 S(1) luminosity out to a radius of at least 250 pc, and (4) more centrally concentrated H2 surface brightness profiles. These observed differences can be interpreted as evidence for Seyfert galaxies having a dynamically cold (in comparison to the bulge) nuclear structure composed of a significant gas reservoir and a relatively young stellar population. This structure is undetected (and possibly does not exist) in quiescent galaxies. The presence of such a nuclear structure in Seyfert galaxies provides evidence for inflow of the surrounding interstellar medium since the nuclear stellar population requires a supply of gas from which to form. The fueling of a Seyfert AGN is thus associated with the formation of a dynamically cold component of gas and stars on scales of hundreds of parsecs. [ABSTRACT FROM AUTHOR]

ABSTRACT We present new ∼1 arcsec resolution data of the dense molecular gas in the central 50-100 pc of four nearby Seyfert galaxies. Plateau de Bure Interferometer (PdBI) observations of HCN and, in two of the four sources, simultaneously HCO+ allow us to carefully constrain the dynamical state of the dense gas surrounding the active galactic nuclei (AGN). The analysis of the kinematics shows large line widths of 100-200 km s−1 full width at half-maximum (FWHM) that can only partially arise from beam smearing of the velocity gradient. The observed morphological and kinematic parameters (dimensions, major axis position angle, red and blue channel separation, and integrated line width) are well reproduced by a thick disc, where the emitting dense gas has a large intrinsic dispersion (20-40 km s−1), implying that it exists at significant scale heights (25-30 per cent of the disc radius). To put the observed kinematics in the context of the starburst and AGN evolution, we estimate the Toomre Q parameter. We find this is always greater than the critical value, i.e. Q is above the limit such that the gas is stable against rapid star formation. This is supported by the lack of direct evidence, in these four Seyfert galaxies, for on-going star formation close around the AGN. Instead, any current star formation tends to be located in a circumnuclear ring. We conclude that the physical conditions are indeed not suited to star formation within the central ∼100 pc. [ABSTRACT FROM AUTHOR]

As part of an extensive study of the physical properties of active galactic nuclei (AGNs) we report high spatial resolution near-IR integral-field spectroscopy of the narrow-line region (NLR) and coronal-line region (CLR) of seven Seyfert galaxies. These measurements elucidate for the first time the two-dimensional spatial distribution and kinematics of the recombination line Bry and high-ionization lines [Si VI], [Al IX], and [Ca VIII] on scales <300 pc from the AGN. The observations reveal kinematic signatures of rotation and outflow in the NLR and CLR. The spatially resolved kinematics can be modeled as a combination of an outflow bicone and a rotating disk coincident with the molecular gas. High-excitation emission is seen in both components, suggesting it is leaking out of a clumpy torus. While NGC 1068 (Seyfert 2) is viewed nearly edge-on, intermediate-type Seyferts are viewed at intermediate angles, consistent with unified schemes. A correlation between the outflow velocity and the molecular gas mass in r < 30 pc indicates that the accumulation of gas around the AGN increases the collimation and velocity of the outflow. The outflow rate is 2-3 orders of magnitude greater than the accretion rate, implying that the outflow is mass loaded by the surrounding interstellar medium (ISM). In half of the observed AGNs, the kinetic power of the outflow is of the order of the power required by two-stage feedback models to be thermally coupled to the ISM and to match the MBH-σ* relation. In these objects, the radio jet is clearly interacting with the ISM, indicative of a link between jet power and outflow power. [ABSTRACT FROM AUTHOR]

It is now well established that all galaxies with a massive bulge component harbour a central supermassive black hole (SMBH). The mass of the SMBH correlates with bulge properties such as the bulge mass and the velocity dispersion, which implies that the bulge and the central BH of a galaxy have grown together during the formation process. As part of an investigation of the dependence of the SMBH mass on bulge types and formation mechanisms, we present measurements of SMBH masses in two pseudo-bulge galaxies. The spiral galaxy NGC 3368 is double-barred and hosts a large pseudo-bulge with a tiny classical bulge component at the very centre. The S0 galaxy NGC 3489 has only a weak large-scale bar, a small pseudo-bulge and a small classical bulge. Both galaxies show weak nuclear activity in the optical, indicative of the presence of an SMBH. We present high-resolution, adaptive-optics-assisted, near-IR integral-field data of these two galaxies, taken with SINFONI at the Very Large Telescope, and use axisymmetric orbit models to determine the masses of the SMBHs. The SMBH mass of NGC 3368, averaged over the four quadrants, is with an error of , which mostly comes from the non-axisymmetry in the data. For NGC 3489, a solution without a BH cannot be excluded when modelling the SINFONI data alone, but can be clearly ruled out when modelling a combination of SINFONI, OASIS and SAURON data, for which we obtain . Although both galaxies seem to be consistent with the relation, at face value they do not agree with the relation between bulge magnitude and BH mass when the total bulge magnitude (i.e. including both classical bulge and pseudo-bulge) is considered; the agreement is better when only the small classical bulge components are considered. However, taking into account the ageing of the stellar population could change this conclusion. [ABSTRACT FROM AUTHOR]

Our adaptive optics observations of nearby AGN at spatial resolutions as small as 0.″085 show strong evidence for recent, but no longer active, nuclear star formation. We begin by describing observations that highlight two contrasting methods by which gas can flow into the central tens of parsecs. Gas accumulation in this region will inevitably lead to a starburst, and we discuss the evidence for such events. We then turn to the impact of stellar evolution on the further inflow of gas by combining a phenomenological approach with analytical modelling and hydrodynamic simulations. These complementary perspectives paint a picture in which all the processes are ultimately regulated by the mass accretion rate into the central hundred parsecs, and the ensuing starburst that occurs there. The resulting supernovae delay accretion by generating a starburst wind, which leaves behind a clumpy interstellar medium. This provides an ideal environment for slower stellar outflows to accrete inwards and form a dense turbulent disk on scales of a few parsecs. Such a scenario may resolve the discrepancy between the larger scale structure seen with adaptive optics and the small-scale structure seen with VLTI. [ABSTRACT FROM PUBLISHER]

In a survey of 18 nearby Seyfert nuclei, we find evidence for geometrically thick gas disks on scales of tens of parsecs. Mapping the interstellar medium traced by H2 ν = 1–0 S(1) emission using the infrared integral field spectrometers OSIRIS and SINFONI reveals general disk rotation with an additional significant component of random bulk motion implied by the high local velocity dispersion. The size scale of the typical nuclear gas disk is ~30 pc in radius with a comparable vertical height, and the distribution and kinematics suggest the gas is spatially mixed with the nuclear stellar population. Based on the estimated characteristic gas mass fraction of 10%, the average gas mass within this region is ~107M⊙. This suggests column densities of NH ~ 5 × 1023 cm−2, but the significantly lower densities implied by the stellar continuum extinction indicate that the gas distribution on these scales is dominated by dense clumps. We discuss the feasibility of constraining the masses of the central black holes via modeling of the gas disk kinematics, highlighting the importance of properly accounting for the gas velocity dispersion, and the use of these direct mass estimates to calibrate masses derived from the method of reverberation mapping. [ABSTRACT FROM PUBLISHER]

The radio galaxy Fornax A (NGC 1316) is a prominent merger remnant in the outskirts of the Fornax cluster. Its giant radio lobes suggest the presence of a powerful active galactic nuclei (AGN) and thus a central supermassive black hole (SMBH). Fornax A now seems to be in a transition state between active black hole growth and quiescence, as indicated by the strongly declined activity of the nucleus. Studying objects in this evolutionary phase is particularly important in order to understand the link between bulge formation and black hole growth, which is manifested in the relation between black hole mass and bulge velocity dispersion. So far, a measurement of the SMBH mass has not been possible in Fornax A, as it is enshrouded in dust which makes optical measurements impossible. We present high-resolution adaptive optics assisted integral-field data of Fornax A, taken with SINFONI at the Very Large Telescope in the K band, where the influence of dust is negligible. The achieved spatial resolution is 0.085 arcsec, which is about a fifth of the diameter of the expected sphere of influence of the black hole. The stellar kinematics was measured using the region around the CO bandheads at 2.3 μm. Fornax A does not rotate inside the inner ∼3 arcsec. The velocity dispersion increases towards the centre. The weak AGN emission affects the stellar kinematics in the inner ∼0.06 arcsec only. Beyond this radius, the stellar kinematics appears relaxed in the central regions. We use axisymmetric orbit models to determine the mass of the SMBH in the centre of Fornax A. The three-dimensional nature of our data provides the possibility to directly test the consistency of the data with axisymmetry by modelling each of the four quadrants separately. According to our dynamical models, consistent SMBH masses and dynamical mass-to-light ratios Υ are obtained for all quadrants, with [ ] and [ ], confirming the assumption of axisymmetry. For the folded and averaged data, we find and errors). Thus, the black hole mass of Fornax A is consistent within the error with the Tremaine et al. relation, but is a factor of ∼4 smaller than expected from its bulge mass and the Marconi & Hunt relation. [ABSTRACT FROM AUTHOR]

The near-infrared (IR) integral field spectrograph SINFONI at the European Southern Observatory Very Large Telescope opens a new window for the study of central supermassive black holes. With a near-IR spatial resolution similar to Hubble Space Telescope optical and the ability to penetrate dust, it provides the possibility to explore the low-mass end of the relation where so far very few black hole masses were measured with stellar dynamics. With SINFONI, we observed the central region of the low-luminosity elliptical galaxy NGC 4486a at a spatial resolution of ≈0.1 arcsec in the K band. The stellar kinematics were measured with a maximum penalized likelihood method considering the region around the CO absorption band heads. We determined a black hole mass of (90 per cent confidence limit) using the Schwarzschild orbit superposition method including the full two-dimensional spatial information. This mass agrees with the predictions of the relation, strengthening its validity at the lower σ end. [ABSTRACT FROM AUTHOR]

We present results from a survey of nearby AGN using the adaptive optics assisted integral-field spectrometer SINFONI on the VLT. These data enable us to study at high angular resolution (~ 0.″08) the distribution and kinematics of the low-ionization gas traced by the BrΓλ2.17 μm recombination line and [Si vi] λ 1.96 μm, [Al ix] λ 2.04 μm, and [Ca viii] λ 2.32 μm, the most prominent coronal lines in the near-IR. Overall, our results show that the coronal lines extend to a radius similar to that of narrow Brγ emission, mimicking in most cases the narrow-line region (NLR). In addition, the kinematics of the highly ionized species, and most of the Brγ kinematics, is dominated by non-circular motions with higher dispersion along the ionization cones, indicating that material is being accelerated and outflowing from a region very close to the AGN. [ABSTRACT FROM PUBLISHER]