Structure of the Cluster of Galaxies A 548

The hierarchical and dynamical structure of the bimodal cluster of galaxies A 548, consisting of the two components A 548E and A 548W, was investigated. An HTree cluster analysis was used for this purpose. Based on the results of the analysis, three main nuclei, five subgroups, and six triplets of galaxies were distinguished in the cluster. These subgroups lie in regions of local density maxima of the entire cluster. The average radial velocities of the subgroups coincide with local maxima in the V _r distribution of the entire cluster. The members of subgroups are 1.25 stellar magnitudes brighter, on the average, than other galaxies. Based both on the projected positions of the galaxies and on their radial velocities, the field of the cluster has a more uniform structure than does the entire system as a whole. Galaxies with different V _r are unevenly distributed in the cluster: radial velocity increases from the periphery toward the center.