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Mid-infrared imaging of NGC1068 with VISIR at the VLT

E. Galliano·E. Pantin·D. Alloin·P. O. Lagage
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Abstract

High resolution mid-infrared (MIR) images of the central region of NGC1068 have been obtained with VISIR, the multi-mode MIR instrument recently installed at the ESO/VLT on Paranal. A map of the emission at 12.8mic with increased sensitivity over the central 8"x 8" area is discussed. It shows a central core (unresolved along the E-W direction) and an extended emission which draws a spiral pattern similar to that observed on near-infrared images. Patches of MIR emission can be detected up to a distance of 4" from the core. The deconvolved 12.8mic map is fully consistent with previous high-resolution MIR observations. It highlights the structure of the extended emission, already seen on the un-deconvolved image, and allows to identify a set of mid-infrared sources: 7 in the NE quadrant and 5 in the SW quadrant. The MIR emission map is compared with those obtained at comparable angular resolution in the near-infrared and in the [OIII] line emission. The very good correlation between the VISIR map and the HST optical map supports the idea that the MIR emission not associated with the torus arises from dust associated with the narrow line region clouds. The N-S extension of the MIR core (0.44") is then probably simply due to the mixing of the MIR emission from the dusty torus and the MIR emission from NLR cloud B, located only 0.1" to the North.

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E. Galliano, E. Pantin, D. Alloin, P. O. Lagage. 2005-06-03. Mid-infrared imaging of NGC1068 with VISIR at the VLT. https://doi.org/10.1111/j.1745-3933.2005.00064.x

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