Searching for the Dust/Molecular Torus in a Typical AGN using Adaptive Optics

Abstract

Adaptive Optics Systems are now routinely operated on several4 meter class telescopes, allowing to achieve angular resolutionsdown to 70 msec in the near-infrared. Although these Systems have excellentperformances, their use for exploring the physics and structureof AGN is still limited for the following reasons: the limiting magnitudeof the wavefront sensor is too high, the sensitivity of infrareddetectors does not give access to medium/high spectral resolution spectroscopyand the angular resolution achieved does not always fit theapparent size of the physical components responsible for emission featuresclose to the central engine. The new generation of 8 — 10 m classtelescopes bring improvements in this matter. However, some interestingresults have been obtained so far with Adonis, the ESO La Sillaadaptive optics System on the 3.60 meter telescope, in the investigationof AGN structure. In particular, a prominent structure has beendetected in the central arcsec core of NGC 1068, which might featurethe dusty/molecular torus expected on theoretical grounds.