Andisheh Mahdavi

University of Victoria

Dark and Luminous Matter in Clusters of Galaxies

Monday, February 25, 2008, 4:00 p.m.
Refreshments at 3:45 p.m.

ABSTRACT

Clusters of galaxies are dominated by dark matter. We can see the gravitational effect of this dark material on the orbits of cluster members, the thermodynamics of the hot gas, and the lensed shapes of galaxies behind the cluster. I will show that combining multiwavelength data for a single relaxed cluster can yield powerful constraints on its dark matter distribution and on the equation of state of the intracluster plasma. At the same time, as the bullet cluster teaches us, multiwavelength observations of merging clusters can yield significant and perhaps even more interesting constraints on dark matter properties. Both relaxed and merging clusters are well-represented in the Canadian Cluster Comparison Project, an X-ray, optical, and radio survey of fifty nearby clusters. I will conclude by discussing an unusual, massive, X-ray bright core nearly devoid of galaxies at the heart of Abell 520, and will explore its implications for our understanding of the fundamental nature of dark matter.