The physics of the interstellar medium under extreme conditions in Seyfert galaxies

• Applicant: Professor Dr. Andreas Burkert
• Subject Area: Astrophysics and Astronomy
• Term: from 2011 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 205979928

With the help of an optically and geometrically thick toroidal gas and dust structure around the central supermassive black hole, the so-called Unified Scheme of Active Galactic Nuclei geometrically unifies two observed classes of galaxies. Depending on the inclination of this dusty torus, the central active region is visible (Seyfert 1 galaxies) or not (Seyfert 2 galaxies). Despite successful observations with the largest available telescopes and interferometry in the mid-infrared, the detailed structure and physics of these objects as well as their origin is still poorly understood: What are the main drivers of turbulence in the nuclear regions and how do they structure the ISM and fuel the central black hole? How does nuclear activity affect the surrounding ISM? In our proposed model, nuclear star clusters in the central tens of parsec scale region provide the source for the ISM in the nucleus, which finally forms the turbulent torus on parsec scale. Thereby, our model links these two spatial regions, which are both well studied with adaptive optics and interferometric methods for a (common) sample of nearby Seyfert galaxies. The extreme conditions due to the presence of the central supermassive black hole lead to peculiar dynamical and structural properties of the turbulent ISM in galactic nuclei in comparison to our local ISM, which we propose to study in detail with three-dimensional magnetohydrodynamical simulations and their comparison with observations.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1573: Physics of the Interstellar Medium