A Caltech Library Service

Dark Matter Halos from the Inside Out

Taylor, James E. (2010) Dark Matter Halos from the Inside Out. Advances in Astronomy, 2011 . pp. 1-17. ISSN 1687-7969. doi:10.1155/2011/604898.

[img] PDF - Published Version
Creative Commons Attribution.


Use this Persistent URL to link to this item:


The balance of evidence indicates that individual galaxies and groups or clusters of galaxies are embedded in enormous distributions of cold, weakly interacting dark matter. These dark matter “halos” provide the scaffolding for all luminous structures in the universe, and their properties comprise an essential part of the current cosmological model. I review the internal properties of dark matter halos, focussing on the simple universal trends predicted by numerical simulations of structure formation. Simulations indicate that halos should all have roughly the same spherically averaged density profile and kinematic structure and predict simple distributions of shape, formation history, and substructure in density and kinematics, over an enormous range of halo mass and for all common variants of the concordance cosmology. I describe observational progress towards testing these predictions by measuring masses, shapes, profiles, and substructure in real halos using baryonic tracers or gravitational lensing. An important property of simulated halos (possibly the most important property) is their dynamical “age”, or degree of internal relaxation. I review recent gravitational lensing studies of galaxy clusters which will measure substructure and relaxation in a large sample of individual cluster halos, producing quantitative measures of age that are well matched to theoretical predictions.

Item Type:Article
Related URLs:
URLURL TypeDescription
Additional Information:Copyright © 2011 James E. Taylor. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Received 2 July 2010; Accepted 16 August 2010 This work was supported by a Discovery grant from the Natural Sciences and Engineering Research Council of Canada. The auther thanks Anson Wong for providing the data used to make Figure 5. The auther also is happy to acknowledge many useful conversations about dark matter models, astrophysical constraints on dark matter, and the prospects for dark matter identification, with the participants of the Keck Institute for Space Studies workshop “Shedding Light on the Nature of Dark Matter”, which was funded by the W. M. Keck Foundation. Finally, I thank P. Salucci for clarifying the original evidence for dark matter in rotation curves.
Group:Keck Institute for Space Studies
Funding AgencyGrant Number
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Keck Institute for Space Studies (KISS)UNSPECIFIED
Record Number:CaltechAUTHORS:20160218-131349249
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:64569
Deposited By: Colette Connor
Deposited On:20 Feb 2016 00:28
Last Modified:10 Nov 2021 23:32

Repository Staff Only: item control page