19 October 2000CfA Colloquium


Title: Clusters of Galaxies: Forefront Observations and Simulations

Speaker: August C. Evrard

Abstract: Over the last ten years, observational and computational evidence has combined to establish a `canonical' picture for the nature of rich galaxy clusters such as Coma. Despite their ongoing formation as the largest cosmic structures, clusters as a population exhibit scaling properties as tight as those of the elliptical galaxy population. I will discuss the advantages of this regularity for determining cosmological parameters and for predicting the abundance of distant clusters to be seen by next generation observations. In the favored $\Lambda$CDM cosmology, for example, all of $\sim 100,000$ clusters expected in the Sloan Digital Sky Survey area will have X--ray fluxes detectable with current satellites and will be readily visible to Sunyaev-Zel'dovish interferometric searches. The possibility of identifying a mass-limited catalog of clusters complete at all redshifts over perhaps a thousand square degrees of sky lies on our immediate horizon.

Reference for students: Real or Virtual Large-scale Structure? A. Evrard, PNAS, v96, p4228

Lunch with the students will be on Friday, October 20th at 12:00 in A-101.