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We use the Gemini NIFS instrument to map the H22.1218μm and Brγ flux distributions in the inner 0.04–2 kpc of a sample of 36 nearby active galaxies (0.001 ≲ z ≲ 0.056) at spatial resolutions from 4 to 250 pc. We find extended emission in 34 galaxies. In ∼55 per cent of them, the emission in both lines is most extended along the galaxy major axis, while in the other 45 per cent the extent follows a distinct orientation. The emission of H2 is less concentrated than that of Brγ, presenting a radius that contains half of the flux 60 per cent greater, on average. The H2 emission is driven by thermal processes – X-ray heating and shocks – at most locations for all galaxies, where 0.4 6 (seen in 40 per cent of the galaxies), shocks are the main H2 excitation mechanism, while in regions with H2/Brγ < 0.4 (25 per cent of the sample) the H2 emission is produced by fluorescence. The only difference we found between type 1 and type 2 active galactic nucleus (AGN) was in the nuclear emission-line equivalent widths that are smaller in type 1 than in type 2 due to a larger contribution to the continuum from the hot dusty torus in the former. The gas masses in the inner 125 pc radius are in the range 101−104 M⊙ for the hot H2 and 103−106 M⊙ for the ionized gas and would be enough to power the AGN in our sample for 105−108 yr at their current accretion rates.

We have used the Gemini Near-Infrared Integral Field Spectrograph in the J and K bands to map the distribution, excitation, and kinematics of the ionized H ii and warm molecular gas H2, in the inner few 100 pc of six 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 H2 gas show distinct kinematics: while the H2 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 H2 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 H2 gas. The total H ii masses cover the range 2×105--2×107 M⊙, with surface mass densities in the range 3–150 M⊙ pc−2, while for the warm H2 the values are 103–4 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 forms new stars the star formation rates, obtained from the Kennicutt–Schmidt scaling relation, are in the range 1–260 × 10−3 M⊙ yr−1. But the gas will also – at least in part – be ejected as the observed outflows

We present a spatially resolved stellar population study of the inner∼200 pc radius ofNGC 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 thestellar 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 onewith intermediate-age stars (50 Myr2 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−1and foundno signatures of non-thermal featureless continuum and hot dust emission, supporting thescenario 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.

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.