Jacob Isbell (USA)
isbell @ mpia.de
First interferometric imaging of the central dust distribution in AGN with MATISSE @ VLTIBD
It is widely held that dusty donut-shaped tori are found in the centers of galaxies, and that the orientation of the torus leads to the different observed properties of Type 1 and Type 2 AGN. Moreover, the gas in the torus provides fuel for accretion onto the central supermassive black hole. In order to understand how AGN are powered, it is clear that we need to understand the structure of the tori. Recent observations with MIDI have challenged the standard axial-symmetric torus model, but detailed observations exist for only the brightest AGN. This project aims to use MATISSE --the second-generation mid-infrared interferometer at the VLTI-- to ease the tension between models and the MIDI observations. MATISSE can combine all 4 8m telescopes of the VLTI, providing 6 baselines and 3 closure phase loops. This will allow us to create high-resolution images of the tori for the first time, an important improvement over the simplified models used to describe MIDI observations. Using the new chromatic images of the tori in nearby AGN, we plan to test the Unified AGN Model and probe these structures with unprecedented detail.
Supervisors: Klaus Meisenheimer, Joerg-Uwe Pott (MPIA)