Probing the coeval evolution of massive galactic bulges and black holes

• Applicant: Dr. Knud Jahnke
• Subject Area: Astrophysics and Astronomy
• Term: from 2007 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 36371730

Since recently we know that likely all Galaxies have a central black hole, with a mass proportional to the mass of the surrounding bulge of the galaxy: The evolution of galaxies and their central black holes is coupled, the underlying physics however are unknown. If the black hole grows by infall of matter, an enourmous amount of radiation-energy is emitted, the nucleus of the galaxy turns into a quasar: the most luminous class of objects in the Universe. Together with the knowledge that quasar host galaxies are more frequently seen colliding with other galaxies, and have more commonly amounts of newlyformed stars than inactive galaxies, this suggests that quasar-activity is triggered by galaxy collisions, and that the coupling of masses is occuring during this quasar-phase.In order to investigate this coupling-phenomenon, I have the largest and best datasets from the Hubble Space Telescope and Very Large Telescope available that exist to study quasar host galaxies. I want to use these data to investigate the causes for the coupling: 1) Did the mass-relation evolve since the early Universe? Can we determine a timescale between galaxy collisions and onset of quasar activity? How did the host galaxies look before the collision? 4) How did quasar host galaxies evolve since the early Universe?

• DFG Programme: Independent Junior Research Groups