Dusty tori in active galactic nuclei

Many galaxies host supermassive black holes with masses of millions to billions of solar masses in their centres. The growth of the black holes is fundamental for the evolution of galaxies. A toroidal distribution of gas and dust, the so-called dusty torus, plays a major role as a reservoir of material for the accretion onto the black hole. Only since a few years it is possible to study the compact structures and physical properties of such tori directly using infrared interferometry.