THE SUPERCLUSTER-VOID NETWORK .1. THE SUPERCLUSTER CATALOG AND LARGE-SCALE DISTRIBUTION

We investigate the distribution of superclusters and voids using a new catalogue of superclusters of rich clusters of galaxies which extends up to a redshift of z = 0.12. The new catalogue contains 220 superclu sters of rich clusters, of which 90 superclusters have been determined for the first time. Among them there are several very rich superclust ers, containing at least eight member clusters. We demonstrate that tw o thirds of very rich superclusters are concentrated to a Dominant Sup ercluster Plane which is situated at a right angle with respect to the plane of the Local Supercluster and adjacent nearby superclusters. We apply several methods to estimate the characteristic distance between superclusters. The results indicate consistently the presence of a qu ite regular supercluster-void network with scale of approximate to 120 h(-1) Mpc. Comparison with random supercluster catalogues shows signi ficant differences between spatial distributions of real and random su perclusters. We determine the selection function of the sample of clus ters and suggest that the mean true space density of Abell clusters is 2.6 10(-5) h(3) Mpc(-3), twice the conventionally used value(1).