Statistical Analysis of Catalogs of Extragalactic Objects. II. the Abell Catalog of Rich Clusters
Abstract
We present the results of a powerspectrum analysis of the distribution of the clusters in the Abell catalog. We find clear and direct evidence of superclusters with small angular scale, in agreement with the recent study of Bogart and Wagoner, and we find that the degree and angular scale of the apparent superclustering varies with distance in the manner expected if the clustering is intrinsic to the spatial distribution rather than a consequence of patchy local obscuration. The observations can be fitted to a spatial covariance function such that the probability of finding a cluster within 20h 1 Mpc of a randomly chosen cluster is about 10 times the probability for a strictly random distribution (h = Hubble's constant in units of 100 km s  1 Mpc 1). The observed smallscale structure corresponds to an average of 2 to 3 clusters per supercluster. Although the distribution of clusters at large angular scale clearly is not uniform, we find no basis on the present evidence for deciding whether this is due to local obscuration or to largescale ( 600h 1 Mpc) density irregularities with density contrast on the order of 30 percent (rms). Subject headings: cosmology  galaxies, clusters of
 Publication:

The Astrophysical Journal
 Pub Date:
 November 1973
 DOI:
 10.1086/152453
 Bibcode:
 1973ApJ...185..757H