VLTI: current observations and future prospects for AGN studies
Klaus Meisenheimer
  
The main content of my lecture will be the discussion of  the current status of
mid-infrared interferometry of the central dust distribution in nearby AGN.
This will rely mostly on MIDI observations at the VLTI during guaranteed time
(carried out by my group in Heidelberg and a group in Leiden), as well as on
new models of the dust torus, developed by Schartmann et al. at the MPIA.  At
the end, I also will outline the next steps in interferometric AGN studies and
advertise new opportunities which will open up at the VLTI in the coming years.

PART I of the lecture will present observational methods, results and
interpretation of the data from observations with the MID-infrared
interferometric Instrument (MIDI) of the dust tori in the two closest Seyfert 2
galaxies: the Circinus galaxy and NGC 1068. New numerical models will be used
to interpret the results. The confrontation between current observations and
models will point to severe gaps in our insight into the detailed dust
distribution, which have to be addressed by future observations with the VLTI.

PART II will discuss first results obtained by MIDI on other AGN, including the
nearby radio galaxy and merger Centaurus A and more distant and more luminous
Seyfert galaxies. Present observational limits of the VLTI and prospects to
overcome those will be outlined.  With examples for future observational
programs I will try to encourage the students to participate in interferometric
AGN research.  Finally, I will point to the entirely new opportunities which
will open up as soon as AMBER and PRIMA become fully operational at the VLTI,
and will advertise the capabilities of the second generation instruments
planned for the VLTI.