Astronomy and Astrophysics – Astrophysics
Scientific paper
1997-03-03
Astronomy and Astrophysics
Astrophysics
20 pages, 16 figures included. submitted to MNRAS. Also available at http://saguaro.as.arizona.edu/~matthias/preprints.html
Scientific paper
The formation of galaxy clusters in hierarchically clustering universes is investigated by means of high resolution N-body simulations. The simulations are performed using a newly developed multi-mass scheme which combines a PM code with a high resolution N-body code. Numerical effects due to time stepping and gravitational softening are investigated as well as the influence of the simulation box size and of the assumed boundary conditions. Special emphasis is laid on the formation process and the influence of various cosmological parameters. Cosmogonies with massive neutrinos are also considered. Differences between clusters in the same cosmological model seem to dominate over differences due differing background cosmogony. The cosmological model can alter the time evolution of cluster collapse, but the merging pattern remains fairly similar, e.g. number of mergers and mass ratio of mergers. The gross properties of a halo, such as its size and total angular momentum, also evolve in a similar manner for all cosmogonies and can be described using analytical models. It is shown that the density distribution of a halo shows a characteristic radial dependence which follows a power law with a slope of $\alpha=-1$ at small and $\alpha=-3$ at large radii, independent of the background cosmogony or the considered redshift. The shape of the density profiles follows the generic form proposed by Navarro et al. (1996) for all hierarchically clustering scenarios and retains very little information about the formation process or the cosmological model. Only the central matter concentration of a halo is correlated to the formation time and therefore to the corresponding cosmogony. We emphasise the role of non-radial motions of the halo particles in the evolution of the density profile.
Huss Andreas
Jain Bhuvnesh
Steinmetz Matthias
No associations
LandOfFree
The Formation and Evolution of Clusters of Galaxies in Different Cosmogonies 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 The Formation and Evolution of Clusters of Galaxies in Different Cosmogonies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Formation and Evolution of Clusters of Galaxies in Different Cosmogonies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-47127