Dark matter halo concentrations in the Wilkinson Microwave Anisotropy Probe year 5 cosmology
Abstract
We use a combination of three large N-body simulations to investigate the dependence of dark matter halo concentrations on halo mass and redshift in the WMAP year 5 cosmology. The median relation between concentration and mass is adequately described by a power-law for halo masses in the range 10^11 - 10^15 Msol/h and redshifts z < 2, regardless of whether the halo density profiles are fit using NFW or Einasto profiles. Compared with recent analyses of the Millennium Simulation, which uses a value of sigma_8 that is higher than allowed by WMAP5, z = 0 halo concentrations are reduced by factors ranging from 23 per cent at 10^11 Msol/h to 16 per cent at 10^14 Msol/h. The predicted concentrations are much lower than inferred from X-ray observations of groups and clusters.
Keywords
Cite
@article{arxiv.0804.2486,
title = {Dark matter halo concentrations in the Wilkinson Microwave Anisotropy Probe year 5 cosmology},
author = {Alan R. Duffy and Joop Schaye and Scott T. Kay and Claudio Dalla Vecchia},
journal= {arXiv preprint arXiv:0804.2486},
year = {2011}
}
Comments
6 pages, 4 figures, Accepted by MNRAS letters. Version 4: Typo fixed