The MX Northern Abell Cluster Survey II: The Abell/ACO Cluster Redshifts and Spatial Analyses

Abstract

The MX Northern Abell Cluster Survey II is the final stage of a program designed to observe rich Abell clusters with m10 ≤ 17.0. We present 1542 new galaxy redshifts within 117 R ≥ 1 Abell cluster fields that have 16.9 ≤ m10 ≤ 17.0, 0h ≤ α ≤ 24h, -17° ≤ δ ≤ 90°, and |b| ≥ 30°. Of the 117 clusters observed for the MX Survey II, 105 new cluster redshifts were obtained with an average of eight cluster member galaxy redshifts. We update the m10-z estimator for Abell clusters and calculate the spatial number density of Abell clusters to be c = (8.25 ± 1.9) × 10-6 h3 Mpc-3 within z = 0.10. All R ≥ 1 Abell and ACO clusters with measured redshifts were combined to calculate the two-point spatial correlation function ξ(r) = (r/ro)γ for the largest complete sample of rich clusters to date. We find 18.6 ≤ ro ≤ 21.0 h-1 Mpc and -2.03 ≤ γ ≤ -1.95. The slope and correlation length are very robust and remain unaffected by the exclusion of compact and dense superclusters or by accounting for line-of-sight anisotropies, which are explained by the existence of three observationally confirmed and extended superclusters.