Astronomy and Astrophysics – Astrophysics
Scientific paper
1999-06-30
Mon.Not.Roy.Astron.Soc.311:576-588,2000
Astronomy and Astrophysics
Astrophysics
30 pages, Latex, 18 figures included, submitted to MNRAS
Scientific paper
10.1046/j.1365-8711.2000.03077.x
We incorporate a simple scheme for the growth of supermassive black holes into semi-analytic models that follow the formation and evolution of galaxies in a cold dark matter dominated Universe. We assume that supermassive black holes are formed and fuelled during major mergers. If two galaxies of comparable mass merge, their central black holes coalesce and a few percent of the gas in the merger remnant is accreted by the new black hole over a timescale of a few times 10^7 years. With these simple assumptions, our model not only fits many aspects of the observed evolution of galaxies, but also reproduces quantitatively the observed relation between bulge luminosity and black hole mass in nearby galaxies, the strong evolution of the quasar population with redshift and the relation between the luminosities of nearby quasars and those of their host galaxies. The strong decline in the number density of quasars from z=2 to z=0 is due to the combination of three effects: i) a decrease in the merging rate, ii) a decrease in the amount of cold gas available to fuel black holes, and iii) an increase in the timescale for gas accretion. In a LCDM cosmology the predicted decline in the total content of cold gas in galaxies is consistent with that inferred from observations of damped Lyman-alpha systems. Our results strongly suggest that the evolution of supermassive black holes, quasars and starbursts is inextricably linked to the hierarchical build-up of galaxies.
Haehnelt Martin
Kauffmann Guinevere
No associations
LandOfFree
A Unified Model for the Evolution of Galaxies and Quasars does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A Unified Model for the Evolution of Galaxies and Quasars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Unified Model for the Evolution of Galaxies and Quasars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-462542