The large-scale environment of groups and clusters of galaxies

Abstract

It appears that the dynamical status of clusters and groups of galaxies is related to the large-scale structure of the Universe. A few interesting trends have been established:

(1) The Cluster Substructure-Alignment Connection by which clusters show a strong correlation between their tendency to be aligned with their neighbors and their dynamical state (as indicated by the existence of significant substructres).

(2) The Cluster Dynamics-Cluster Clustering Connection by which dynamically young clusters are more clustered than the overall cluster population.

(3) The Cluster-Supercluster Alignment Connection by which clusters of galaxies show a statistical significant tendency to be aligned with the projected major axis orientation of their parent supercluster.

(4) The Galaxy Alignment-Cluster Dynamics Connection by which red-sequence cluster bright galaxies show a significant trend to be aligned with their parent cluster major axis, especially in dynamically young clusters.

(5) The Group Richness-Shape Connection by which groups of galaxies are flatter the poorer they are.

These are strong indications that clusters develop in a hierarchical fashion by anisotropic merging of smaller units along the large-scale filamentary structures within which they are embedded.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html