标题： 星系团的性质：质量与关联函数 显示英文标题

标题： Properties of Galaxy Clusters: Mass and Correlation Functions

摘要： 我们分析了三个冷暗物质（CDM）宇宙的并行N体模拟，以研究星系团的丰度和聚类情况。 这些模拟覆盖的体积与即将进行的SDSS相当。 我们能够对红移大于1的星系团特性进行稳健测量。 我们使用两种独立的公开领域组探测器（FOF & HOP）提取晕，并发现结果一致。 星系团的相关函数与基于Mo & White（1996）开发的拉格朗日偏差方案和质量函数的Press-Schechter（PS）形式主义的简单解析公式非常吻合。 开放CDM模型的R_0--D_c关系与APM星系团巡天的结果良好一致。 SCDM宇宙在质量函数的形状和演化方面与PS形式主义预测相比表现出稳健的偏差。 具有低sigma_8归一化或小形状参数Gamma的临界模型相比PS预测显示出更多的大质量星系团。 当以星系团归一时，z=1时的SCDM宇宙中温度高于7keV的星系团数量是PS预测的10倍。 如果将delta_c（坍缩的外推线性理论阈值）的值修订为delta_c(z) = 1.685[(0.7/sigma_8)(1+z)]{-0.125}，则SCDM的解析质量和N体质量函数之间的吻合度可以得到改善。 我们对SCDM宇宙局部星系团丰度推断的波动幅度的最佳估计为sigma_{8} = 0.5 \pm 0.04。 然而，临界密度宇宙中预测的温度函数与z=0.33观测到的温度函数之间的差异仍然存在。 （摘要） 显示英文摘要

摘要： We analyse parallel N-body simulations of three Cold Dark Matter (CDM) universes to study the abundance and clustering of galaxy clusters. The simulations cover a volume comparable to the forthcoming SDSS. We are able to make robust measurements of cluster properties to a redshift larger than unity. We extract halos using two independent, public domain group finders (FOF & HOP) and find consistent results. The correlation function of clusters is in very good agreement with a simple analytic prescription based upon a Lagrangian biasing scheme developed by Mo & White (1996) and the Press-Schechter (PS) formalism for the mass function. The R_0--D_c relation for the open CDM model is in good agreement with the results from the APM Cluster Survey. The SCDM universe shows a robust deviation in the shape and evolution of the mass function when compared with that predicted by the PS formalism. Critical models with a low sigma_8 normalization or small shape parameter Gamma show an excess of massive clusters compared with the PS prediction. When cluster normalized, the SCDM universe at z =1 contains 10 times more clusters with temperatures greater than 7keV, compared with the PS prediction. The agreement between the analytic and N-body mass functions of SCDM can be improved if the value of the delta_c (the extrapolated linear theory threshold for collapse) is revised to be $ delta_c(z) = 1.685[(0.7/sigma_8)(1+z)]^{-0.125}. Our best estimate for the amplitude of fluctuations inferred from the local cluster abundance for SCDM is sigma_{8} = 0.5 \pm 0.04. However, the discrepancy between the temperature function predicted in a critical density universe and that observed at z=0.33 (Henry et al. 1998) remains. (abridged)