We have conducted an automated search for galaxy clusters within a contiguous 16 deg2 I-band survey in the north Galactic hemisphere. A matched filter detection algorithm identifies 444 cluster candidates in the range 0.2 z 1.2. The full catalog is presented along with the results from a follow-up spectroscopic survey. The estimated redshift distribution of the cluster candidates is consistent with a constant comoving density over the range 0.2 ≤ zest ≤ 0.8. A decline in the cluster space density by more than a factor of 3 over this redshift range is rejected at the greater than 99.9% confidence level. We find that the space density of Λcl ≥ 40 clusters in our survey lies in the range (1.6-1.8) × 10-5 h Mpc-3, ~1.5 times higher than the local distribution of comparably rich Abell richness class ≥0 clusters. The Λcl distribution is consistent with a power law. The discrepancy between the space density of Abell clusters and the clusters in this survey declines quickly as Λcl increases, suggesting that the difference at lower richness is due to significant incompleteness in the Abell catalog. A percolation analysis reveals that 10%-20% of the spectroscopically confirmed distant clusters are linked into superclusters at overdensities between 10 δρ/ρ 50, similar to what is seen in the local cluster distribution. This suggests that there has been little evolution of the cluster-cluster correlation length for z 0.5.
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机译：我们在北银河半球连续16度I波段调查中对星系团进行了自动搜索。匹配的过滤器检测算法可识别范围为0.2 z 1.2的444个候选簇。完整的目录与后续光谱调查的结果一起显示。估计的候选簇的红移分布与在0.2≤zest≤0.8范围内的恒定共同移动密度一致。在大于99.9％的置信度下，在这个红移范围内，群集空间密度的下降幅度超过3倍被拒绝。我们发现调查中Λcl≥40个星团的空间密度在（1.6-1.8）×10-5 h Mpc-3范围内，比相当丰富的Abell富集等级≥0星团的局部分布高约1.5倍。 Λcl分布与幂定律一致。随着Λcl的增加，本次调查中Abell群集与群集之间的空间密度差异迅速减小，这表明较低富度的差异是由于Abell目录中的显着不完整所致。渗滤分析表明，经光谱确认的远距离簇的10％-20％在10 <δρ/ρ<50的超密度下与超级簇相连，这与局部簇分布相似。这表明对于z 0.5，集群-集群相关长度几乎没有变化。
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