Large-scale structure and motion traced by galaxy clusters

The rich clusters of galaxies constituting the high-density peaks of the distribution of galaxies are presently used as tracers of the large-scale structure. Attention is given to the Abell, Shectman, and Zwicky cluster types. Evidence adduced for the cluster correlation function encompasses the scaling of the angular correlation with depth, the consistency of the projected and redshift cluster correlation functions, and the cluster correlation function's yielding of consistent results in different, large regions of the sky. The increase of correlation strength with richness implies that rich, luminous systems are more strongly clustered at a given separation than poorer systems. 62 refs