The UZC-SSRS2 Group Catalog

Abstract

We apply a friends-of-friends algorithm to the combined Updated Zwicky Catalog and Southern Sky Redshift Survey to construct a catalog of 1168 groups of galaxies; 411 of these groups have five or more members within the redshift survey. The group catalog covers 4.69 sr, and all groups exceed the number density contrast threshold, δρ/ρ = 80. We demonstrate that the groups catalog is homogeneous across the two underlying redshift surveys; the catalog of groups and their members thus provides a basis for other statistical studies of the large-scale distribution of groups and their physical properties. The median physical properties of the groups are similar to those for groups derived from independent surveys, including the ESO Key Programme and the Las Campanas Redshift Survey. We include tables of groups and their members.