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We present two-dimensional gaseous kinematics of the inner 1.2 × 1.8 kpc2 of the Seyfert 2 galaxy NGC 3081, from optical spectra (5600-7000 Å) obtained with the Gemini Multi Object Spectrograph integral field spectrograph on the Gemini North telescope at a spatial resolution of ≈100 pc.We have identified two components in the line emitting gas. A narrower component (full width at half-maximum, FWHM ≈ 60-100 km s-1), which appears to be gas in the galaxy disc, and which shows a distorted rotation pattern, is observed over the whole field of view. A broader component (FWHM ≈ 150-250 km s-1) is present in the inner ≈2 arcsec (200 pc) and shows blueshifts and redshifts in the near and far sides of the galaxy, respectively, consistent with a bipolar outflow. Assuming this to be the case, we estimate that the mass outflow rate in ionized gas(Mout) is between 1.9 ×10-3 and 6.9 ×10-3 M☉ yr-1. The subtraction of a rotation model from the narrower component velocity field reveals a pattern of excess blueshifts of ≈50 km s-1 in the far side of the galaxy and similar excess redshifts in the near side, which are cospatial with a previously known nuclear bar.We interpret these residuals as due to gas following non-circular orbits in the barred potential. Under the assumption that these motions may lead to gas inflows, we estimate an upper limit for the mass inflow rate in ionized gas of ϕ ≈ 1.3 ×10-2 M☉ yr-1. [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]

We present optical integral field spectroscopy - obtained with the Gemini Multi-Object Spectrograph - of the inner 4.0 × 5.8 kpc2 of the narrow line radio galaxy 3C 33 at a spatial resolution of 0.58 kpc. The gas emission shows three brightest structures: a strong knot of nuclear emission and two other knots at ≈1.4 kpc south-west and north-east of the nucleus along the ionization axis. We detect two kinematic components in the emission lines profiles, with a 'broader component' (with velocity dispersion σ ≥ 150 km s--1 )being dominant within an ~1 kpc wide strip ('the nuclear strip') running from the south-east to the north-west, perpendicular to the radio jet, and a narrower component (σ ≤ 100 km s--1 ) dominating elsewhere. Centroid velocity maps reveal a rotation pattern with velocity amplitudes reaching ~± 350 km s--1 in the region dominated by the narrow component, while residual blueshifts and redshifts relative to rotation are observed in the nuclear strip, where we also observe the highest values of the [NII]/Hα, [SII]/Hα and [OI]/Hα line ratios, and an increase of the gas temperature (~18 000 K), velocity dispersion and electron density (~500 cm--3 ). We interpret these residuals and increased line ratios as due to a lateral expansion of the ambient gas in the nuclear strip due to shocks produced by the passage of the radio jet. The effect of this expansion in the surrounding medium is very small, as its estimated kinetic power represents only 2.6 × 10--5 - 3.0 × 10--5 of the AGN bolometric luminosity. A possible signature of inflow is revealed by an increase in the [OI]/Hα ratio values and velocity dispersions in the shape of two spiral arms extending to 2.3 kpc north-east and south-west from the nucleus. [ABSTRACT FROM AUTHOR]

We present two-dimensional ionized gas and stellar kinematics in the inner 1.4 × 1.9 kpc2 of the Seyfert 2 galaxy ESO 153-G20 obtained with the Gemini-South/Gemini multi-object spectrograph integral field unit (GMOS-IFU) at a spatial resolution of ~250 pc and spectral resolution of 36 km s−1. Strong [O  iii ], Hα, [N  ii ] and [S  ii ] emission lines are detected over the entire field of view. The stellar kinematics trace circular rotation with a projected velocity amplitude of ±96 km s−1, a kinematic major axis in position angle of 11°, and an average velocity dispersion of 123 km s−1. To analyse the gas kinematics, we used aperture spectra, position–velocity diagrams and single/double Gaussian fits to the emission lines. All lines show two clear kinematic components: a rotating component that follows the stellar kinematics, and a larger-dispersion component, close to the systemic velocity (from which most of the [O  iii ] emission comes), mainly detected to the south-west. We interpret this second component as gas outflowing at ∼400 km s−1 in a compact (300 pc) ionization cone with a half-opening angle ≤40°. The counter-cone is probably obscured behind a dust lane. We estimate a mass outflow rate of 1.1 M |$\odot$| yr−1, 200 times larger than the estimated accretion rate on to the supermassive black hole, and a kinetic to radiative power ratio of 1.7 × 10−3. Bar-induced perturbations probably explain the remaining disturbances observed in the velocity field of the rotating gas component. [ABSTRACT FROM AUTHOR]

As part of a high-resolution observational study of feeding and feedback processes occurring in the vicinity of the active galactic nucleus in 40 galaxies, we observed the inner 3 |${^{\prime\prime}_{.}}$| 5 × 5 arcsec of the nearby spiral and Seyfert 2 galaxy UGC 2024 with the integral field unit of the Gemini-South Telescope. The observations enabled a study of the stellar and gas kinematics in this region at a spatial resolution of 0 |${^{\prime\prime}_{.}}$| 5 (218 pc), and a spectral resolution of 36  km s−1 over the wavelength range 4100–7300 Å. For the strongest emission-lines (H  β , [ |$\rm{O\,{\small III}}$| ] λ5007 Å, H  α , [ |$\rm{N\,{\small II}}$| ] λ6584 Å, and [ |$\rm{S\,{\small II}}$| ] λλ6717,6731 Å) we derived maps of the flux, radial velocity, and velocity dispersion. The flux distribution and kinematics of the [ |$\rm{O\,{\small III}}$| ] emission line are roughly symmetric around the nucleus: the radial velocity is close to systemic over the full field of view. The kinematics of the other strong emission lines trace both this systemic velocity component, and ordered rotation (with kinematic centre 0 |${^{\prime\prime}_{.}}$| 2 north-west of the nucleus). The stellar continuum morphology and kinematics are, however, asymmetrical around the nucleus. We interpret these unusual kinematics as the superposition of a component of gas rotating in the galaxy disc plus a 'halo' component of highly ionized gas. This halo either traces a quasi-spherical fountain with average radial velocity 200 km s−1, in which case the total nuclear outflow mass and momentum are 2 × 105 M⊙ and 4 × 107 M⊙ km s−1, respectively, or a dispersion supported halo created by a past nuclear starburst. [ABSTRACT FROM AUTHOR]

We observed the nuclear region of the galaxy NGC 1365 with the integral field unit of the Gemini Multi Object Spectrograph mounted on the GEMINI-South telescope. The field of view covers 13 ? 6 arcsec²(1173 ? 541 pc²) centred on the nucleus, at a spatial resolution of 52 pc. The spectral coverage extends from 5600 to 7000 Å, at a spectral resolution R = 1918. NGC 1365 hosts a Seyfert 1.8 nucleus, and exhibits a prominent bar extending out to 100 arcsec (9 kpc) from the nucleus. The field of view lies within the inner Lindblad resonance. Within this region, we found that the kinematics of the ionized gas (as traced by [O I], [N II], Ha, and [S II]) is consistent with rotation in the large-scale plane of the galaxy. While rotation dominates the kinematics, there is also evidence for a fan-shaped outflow, as found in other studies based on the [O III] emission lines. Although evidence for gas inflowing along nuclear spirals has been found in a few barred galaxies, we find no obvious signs of such features in the inner kiloparsec of NGC 1365. However, the emission lines exhibit a puzzling asymmetry that could originate from gas which is slower than the gas responsible for the bulk of the narrow-line emission. We speculate that it could be tracing gas which lost angular momentum, and is slowly migrating from the inner Lindblad resonance towards the nucleus of the galaxy. [ABSTRACT FROM AUTHOR]