A catalog of Nearby Poor Clusters of Galaxies

Abstract

A catalog of 732 optically selected, nearby poor clusters of galaxies covering the entire sky north of [3¡ declination is presented. The poor clusters, called WBL clusters, were identiÐed as concentrations of three or more galaxies with photographic magnitudes brighter than 15.7, possessing a galaxy surface overdensity of 104@3. These criteria are consistent with those used in the identiÐcation of the original Yerkes poor clusters, and this new catalog substantially increases the sample size of such objects. These poor clusters cover the entire range of galaxy associations up to and including Abell clusters, systematically including poor and rich galaxy systems spanning over 3 orders of magnitude in the cluster mass function. As a result, this new catalog contains a greater diversity of richness and structures than other group catalogs, such as the Hickson and Yerkes catalogs. The information on individual galaxies includes redshifts and cross-references to other galaxy catalogs. The entries for the clusters include redshift (where available) and cross-references to other group and cluster catalogs.