Astronomy and astrophysics

The Role of Neutral Hydrogen in the Evolution of Nearby Radio Galaxies

by Christian Struve (Onsala Space Observatory)

Europe/Stockholm
FA31

FA31

Description
Cold gas may play an important role in the triggering of Active Galactic Nuclei (AGN). However, direct evidence that cold gas fuels the AGN is still missing. I will present a study which aims at investigating the role of neutral hydrogen (HI) in the evolution of nearby radio sources and their hosts. Our results of the cold gas environment of a sample of radio galaxies, as well as a detailed study of the HI disk of Centaurus A, indicate that gas-rich galaxy mergers and interactions are likely not the main mechanism causing radio activity. I will show that on the 100 pc scale circumnuclear HI disks exist in several radio galaxies and discuss the role they play for feeding the black hole.