KIPAC Tea Talk: Gunther Hasinger (Hawaii)

Cosmic Evolution of Active Galactic Nuclei

When May 22, 2012
from 11:00 AM to 12:00 PM
Where Campus, Varian Room 355
Add event to calendar vCal

The X-ray sky is dominated by a diffuse extragalactic background radiation, which our team, together with others, was able to resolve almost completely into discrete sources using the X-ray satellites ROSAT, Chandra and XMM-Newton - we observe the growth phase of the population of supermassive black holes throughout the history of the Universe. Indeed, the mass distribution of black holes in local galaxies is well traced by the evolution of the accreting black hole luminosity function. However, the maximum of high-luminosity objects occurs significantly earlier in the history of the universe (at redshifts 2-3), than that of low-luminosity objects, which have a peak at redshifts below unity. This anti-hierarchical evolution is similar to the down-sizing effect observed in the optical galaxy population and requires different feeding modes in the early and late Universe. Galaxy mergers are likely responsible for the early growth of black holes and bulges, while a different feeding mode - the re-juvenation of black holes in galaxies by the accretion of fresh gas from their environment – may be responsible for the late evolution of both the star formation and AGN activity. This is also confirmed by special correlation analyses, showing that AGN up to redshifts of z=2 live in relatively massive, non-evolving dark matter haloes.

Document Actions
Filed under:
« October 2015 »
Upcoming Events
Cosmology Seminar: Zhen Hou (University of Chicago) Oct 12, 2015 11:00 AM - 12:00 PM — Campus, Varian 355
KIPAC Tea Talk: Garrett Karto Keating (UC Berkeley) Oct 13, 2015 11:00 AM - 12:00 PM — Campus, Varian 355
Astrophysics Colloquium: Olivier Dore (JPL) Oct 15, 2015 11:00 AM - 12:00 PM — Campus, PAB 102/103
KIPAC Tea Talk: Connie Rockosi (UC Santa Cruz) Oct 16, 2015 10:30 AM - 11:30 AM — SLAC, FKB 3rd Floor Conference Room
Cosmology Seminar: Coral Wheeler (UC Irvine) Oct 19, 2015 11:00 AM - 12:00 PM — Campus, Varian 355
Upcoming events…
This site was built using Plone CMS, the Open Source Content Management System. Click for more information.