We use the Gemini Near-Infrared Integral Field Spectrograph (NIFS) to map the stellar kinematics of the inner few hundred parsecs of a sample of 16 nearby Seyfert galaxies, at a spatial resolution of tens of parsecs and spectral resolution of 40 km s −1. We find that the line-of-sight (LOS) velocity fields for most galaxies are well reproduced by rotating disc models. The kinematic position angle (PA) derived for the LOS velocity field is consistent with the large-scale photometric PA. The residual velocities are correlated with the hard X-ray luminosity, suggesting that more luminous active galactic nuclei have a larger impact in the surrounding stellar dynamics. The central velocity dispersion values are usually higher than the rotation velocity amplitude, what we attribute to the strong contribution of bulge kinematics in these inner regions. For 50 per cent of the galaxies, we find an inverse correlation between the velocities and the h 3 Gauss-Hermitte moment, implying red wings in the blueshifted side and blue wings in the redshifted side of the velocity field, attributed to the movement of the bulge stars lagging the rotation. Two of the 16 galaxies (NGC 5899 and Mrk 1066) show an S-shape zero velocity line, attributed to the gravitational potential of a nuclear bar. Velocity dispersion (σ) maps show rings of low-σ values (∼50-80 km s −1) for four objects and 'patches' of low σ for six galaxies at 150-250 pc from the nucleus, attributed to young/ intermediate age stellar populations.
We have used the Gemini Near-Infrared Integral Field Spectrograph (NIFS) in the J and K bands to map the distribution, excitation and kinematics of the ionized H ii and warm molecular gas H 2 , in the inner few 100 pc of 6 nearby active galaxies: NGC 788, Mrk 607, NGC 3227, NGC 3516, NGC 5506, NGC 5899. For most galaxies, this is the first time that such maps have been obtained. The ionized and H 2 gas show distinct kinematics: while the H 2 gas is mostly rotating in the galaxy plane with low velocity dispersion (σ), the ionized gas usually shows signatures of outflows associated with higher σ values, most clearly seen in the [Fe ii] emission line. These two gas species also present distinct flux distributions: the H 2 is more uniformly spread over the whole galaxy plane, while the ionized gas is more concentrated around the nucleus and/or collimated along the ionization axis of its Active Galactic Nucleus (AGN), presenting a steeper gradient in the average surface mass density profile than the H 2 gas. The total H ii masses cover the range 2 × 10 5 − 2 × 10 7 M ⊙ , with surface mass densities in the range 3-150 M ⊙ pc −2 , while for the warm H 2 the values are 10 3−4 times lower. We estimate that the available gas reservoir is at least ≈ 100 times more massive than needed to power the AGN. If this gas form new stars the star-formation rates, obtained from the Kennicutt-schmidt scalling relation, are in the range 1-260× 10 −3 M ⊙ yr −1 . But the gas will also -at least in part -be ejected in the form of the observed otflows.
We have mapped the emission-line flux distributions and ratios as well as the gaseous kinematics of the inner 450 pc radius of the type 1 Seyfert galaxy Mrk 766 using integral field near-infrared J-and K l -band spectra obtained with the Gemini Near Infrared Integral Field Spectrograph at a spatial resolution of 60 pc and velocity resolution of 40 km s −1 . Emission-line flux distributions in ionized and molecular gas extend up to ≈ 300 pc from the nucleus. Coronal [S IX] λ1.2523 µm line emission is resolved, being extended up to 150 pc from the nucleus. At the highest flux levels, the [Fe II] λ1.257 µm line emission is most extended to the south-east, where a radio jet has been observed. The emission-line ratios [Fe II] λ1.2570 µm/Paβ and H 2 λ2.1218 µm/Brγ show a mixture of Starburst and Seyfert excitation; the Seyfert excitation dominates at the nucleus, to the north-west and in an arc-shaped region between 0.2 and 0.6 arcsec to the south-east at the location of the radio jet. A contribution from shocks at this location is supported by enhanced [Fe II]/[P II] line ratios and increased [Fe II] velocity dispersion. The gas velocity field is dominated by rotation that is more compact for H 2 than for Paβ, indicating that the molecular gas has a colder kinematics and is located in the galaxy plane. There is about 10 3 M of hot H 2 , implying ≈10 9 M of cold molecular gas. At the location of the radio jet, we observe an increase in the [Fe II] velocity dispersion (150 km s −1 ), as well as both blueshift and redshifts in the channel maps, supporting the presence of an outflow there. The ionized gas mass outflow rate is estimated to be ≈10 M yr −1 , and the power of the outflow ≈0.08 L bol .
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