标题： SDSS中的星系单元计数分布 显示英文标题

标题： The galaxy counts-in-cells distribution from the SDSS

摘要： 我们利用斯隆数字巡天（SDSS）的数据，确定了红移空间中的三维球形细胞以及二维投影细胞的星系单元数分布。我们发现，SDSS中的宇宙学起伏使不同象限的单元数分布彼此相差高达20%。同时，我们还发现，在这一宇宙学起伏范围内，总体的星系单元数分布与引力准平衡分布和负二项分布均相符。此外，我们还发现，较亮星系的聚类程度比从包含所有光度星系的更大完整样本中随机选择的星系更强烈。这些结果表明，明亮星系可能位于相隔不到约10 Mpc/h的暗物质晕中。 显示英文摘要

摘要： We determine the galaxy counts-in-cells distribution from the Sloan Digital Sky Survey (SDSS) for 3D spherical cells in redshift space as well as for 2D projected cells. We find that cosmic variance in the SDSS causes the counts-in-cells distributions in different quadrants to differ from each other by up to 20%. We also find that within this cosmic variance, the overall galaxy counts-in-cells distribution agrees with both the gravitational quasi-equilibrium distribution and the negative binomial distribution. We also find that brighter galaxies are more strongly clustered than if they were randomly selected from a larger complete sample that includes galaxies of all luminosities. The results suggest that bright galaxies could be in dark matter haloes separated by less than ~10 Mpc/h.