Mid-infrared Interferometry of Active Galactic Nuclei: an Outstanding Scientific Success of the VLTI
Meisenheimer, Klaus; Raban, David; Tristram, Konrad; Schartmann, Marc; Jaffe, Walter; Röttgering, Huub; Burtscher, Leonard
The Messenger, vol. 133, p. 36-41 (2008)
Abstract
Active Galactic Nuclei (AGN) are powered by accretion onto a supermassive black hole. The unified scheme for strongly accreting AGN postulates that the central engine is enshrouded
by a doughnut-shaped structure of gas and dust – the so-called torus. We report observations with the MID-Infrared Interferometric Instrument (MIDI) at the VLT Interferometer,
which resolve the tori in the nearest Seyfert 2 galaxies, and suggest a complex structure, consisting of a compact inner disc embedded in a patchy or filamentary outer torus.
The prominent nearby radio galaxy Centaurus A, however, shows little sign of a torus. Instead, its mid-infrared emission is dominated by non-thermal radiation from the base of
the radio jet. Thus, not all classes of AGN contain a thick torus.
You can get this publication ...