Molecular material within 100 pc around the AGN in NGC1068 from ISAAC/VLT observations

We present near-IR long slit spectroscopic data obtained with ISAAC on VLT/ANTU (ESO/Paranal) to produce Bracket gamma and H2 emission line maps and line profile grids of the central 4"×4" region surrounding the central engine of NGC1068. This paper summarizes the results presented in Galliano & Alloin. The seeing quality together with the use of an 0.3" wide slit and 0.3" slit position offsets allow to perform 2D-spectroscopy at 0.5" spatial resolution. The spectral resolution corresponds to 35km s-1. An asymmetric distribution of H2 emission is observed: no H2 emission is detected at the location of the 2.2 μm continuum core, while two conspicuous H2 knots of are detected at about 1" East and West of the central engine. These knots show a projected velocity difference of 140km s-1 that we interpreted as the signature of a rotating disk of molecular material. The H2 emission line profiles appear highly asymmetric with their low velocity wing being systematically more extended than their high velocity wing. A simple way to account for the changes of the H2 line profiles over the entire 4"×4" region, is to consider that the emission of a radial outflow is superimposed over the emission of the rotating molecular disk. We present a model of such a kinematical configuration and compare our predicted H2 emission line profiles to the observed ones.

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