Fossil Groups in the Millennium Simulation. Evolution of the Brightest Galaxies

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

9 pages, 3 figures, accepted for publication in Astronomy & Astrophysics

Scientific paper

10.1051/0004-6361:200809760

We create a catalogue of simulated fossil groups and study their properties, in particular the merging histories of their first-ranked galaxies. We compare the simulated fossil group properties with those of both simulated non-fossil and observed fossil groups. Using simulations and a mock galaxy catalogue, we searched for massive ($>$ 5 $\times$ 10$^{13} h^{-1} {\cal M}_\odot$) fossil groups in the Millennium Simulation Galaxy Catalogue. In addition, attempted to identify observed fossil groups in the Sloan Digital Sky Survey Data Release 6 using identical selection criteria. Our predictions on the basis of the simulation data are:(a) fossil groups comprise about 5.5% of the total population of groups/clusters with masses larger than 5 x 10$^{13} h^{-1} {\cal M}_\odot$. This fraction is consistent with the fraction of fossil groups identified in the SDSS, after all observational biases have been taken into account; (b) about 88% of the dominant central objects in fossil groups are elliptical galaxies that have a median R-band absolute magnitude of $\sim -23.5-5 log h$, which is typical of the observed fossil groups known in the literature; (c)first-ranked galaxies of systems with $ {\cal M} >$ 5 x 10$^{13} h^{-1} {\cal M}_\odot$, regardless of whether they are either fossil or non-fossil, are mainly formed by gas-poor mergers; (d) although fossil groups, in general, assembled most of their virial masses at higher redshifts in comparison with non-fossil groups, first-ranked galaxies in fossil groups merged later, i.e. at lower redshifts, compared with their non-fossil-group counterparts. We therefore expect to observe a number of luminous galaxies in the centres of fossil groups that show signs of a recent major merger.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Fossil Groups in the Millennium Simulation. Evolution of the Brightest Galaxies 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 Fossil Groups in the Millennium Simulation. Evolution of the Brightest Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fossil Groups in the Millennium Simulation. Evolution of the Brightest Galaxies will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-603571

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.