| Abstract | R_c-band observations of 71 galaxies of early morphological type were obtained using a CCD array on the 1-m telescope of the Special Astrophysical Observatory. These observations are used together with the relation of Kormendy (mu_e-lg R_c) to determine the relative distances of eight clusters in the Corona Borealis supercluster, with a mean accuracy of about 8%. Analysis of its Hubble diagram indicates that this supercluster is one of only a few extremely massive, dynamically isolated galactic systems. It is likely that the compact core of the supercluster, which is made up of five rich clusters, has overcome the global expansion of the Universe due to its high mass density, and is in a stage of rapid gravitational collapse. |
