The AGNIFS survey: distribution and excitation of the hot molecular and ionised gas in the inner kpc of nearby AGN hosts

We use the Gemini NIFS instrument to map the H${}_{2}2.1218\mu$m and Br$\gamma$ flux distributions in the inner 0.04-2 kpc of a sample of 36 nearby active galaxies ($0.001\lesssim z\lesssim 0.056$) at spatial resolutions from 4 to 250 pc. We find extended emission in 34 galaxies. In $\sim$55% of them, the emission in both lines is most extended along the galaxy major axis, while in the other 45% the extent follows a distinct orientation. The emission of H${}_2$ is less concentrated than that of Br$\gamma$, presenting a radius that contains half of the flux 60% greater, on average. The H${}_2$ emission is driven by thermal processes - X-ray heating and shocks - at most locations for all galaxies, where $0.4<H_2\mathrm{/}Br\gamma <6$. For regions where H${}_2$/Br$\gamma >6$ (seen in 40% of the galaxies), shocks are the main H${}_2$ excitation mechanism, while in regions with H${}_2$/Br$\gamma <0.4$ (25% of the sample) the H${}_2$ emission is produced by fluorescence. The only difference we found between type 1 and type 2 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 ${10}^1-{10}^4$ M${}_{\odot }$ for the hot H${}_2$ and ${10}^3-{10}^6$ M${}_{\odot }$ for the ionised gas and would be enough to power the AGN in our sample for ${10}^5-{10}^8$ yr at their current accretion rates.