The abundance and clustering of dark haloes in the standard ΛCDM cosmogony
Abstract
Much evidence suggests that we live in a flat cold dark matter universe with a cosmological constant. Accurate analytic formulae are now available for many properties of the dark halo population in such a Universe. Assuming current `concordance' values for the cosmological parameters, we plot halo abundance against redshift as a function of halo mass, halo temperature, the fraction of cosmic matter in haloes, halo clustering strength, and the clustering strength of the z= 0 descendants of high-redshift haloes. These plots are useful for understanding how nonlinear structure grows in the model. They demonstrate a number of properties that may seem surprising, for example: 109 Msolar haloes are as abundant at z= 20 as L* galaxies are today; 106 K haloes are equally abundant at z= 8 and at z= 0; 10 per cent of all matter is currently in haloes hotter than 1 keV, while more than half is in haloes too cool to trap photo-ionized gas; 1 per cent of all matter at z= 15 is in haloes hot enough to ionize hydrogen; haloes of given mass or temperature are more clustered at higher redshift; haloes with the abundance of present-day L* galaxies are equally clustered at all z < 20; the metals produced by star-formation at z > 10 are more clustered at z= 0 than are L* galaxies.
- Publication:
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Monthly Notices of the Royal Astronomical Society
- Pub Date:
- October 2002
- DOI:
- arXiv:
- arXiv:astro-ph/0202393
- Bibcode:
- 2002MNRAS.336..112M
- Keywords:
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- galaxies: clusters: general;
- galaxies: formation;
- cosmology: theory;
- dark matter;
- large-scale structure of Universe;
- Astrophysics
- E-Print:
- 10 pages, 2 ps figures, version to be published in MNRAS