论文标题
codex集群的聚类
Clustering of CODEX clusters
论文作者
论文摘要
目标。我们分析了大型星系簇样本的自相关函数，该样本用X射线（codex）样本约束，在其中我们特别注意群集定义。这些簇是使用RASS调查选择的X射线，然后使用SDSS的光度法上的代码RedMapper识别为Galaxy簇。我们开发了精确考虑样本选择对聚类的影响的方法，并使用数值模拟证明了它们的鲁棒性。方法。使用Clean Codex样本，该样本是通过应用红移依赖性丰富度选择获得的，我们在$ 0.1 <z <0.3 $和0.3 <z <z <z <0.5 $ redshift bin的$ 0.1 <z <0.3 $中计算了两点自相关功能。我们比较了使用类似的群集质量范围在数值模拟中获得的测量相关函数的偏差与在数值模拟中获得的偏差。结果。通过拟合功率法，我们测量了相关长度$ r_0 = 18.7 \ pm 1.1 $和斜率$γ= 1.98 \ pm 0.14 $，用于完整的红移范围内的相关函数。通过将其他宇宙学参数固定到其WMAP9值中，我们在以下宇宙学条件下重现了相关函数的观察形状：$ω_{m_0} = 0.22^{+0.04} _ { - 0.03} $和$ s_8 =σ_8=σ_8（m_8（m_0}} m_8（m_0}） /0.3)^ {0.5} = 0.85^ {+0.10} _ { - 0.08} $，带有$σ_{ω_{m_0}} = 0.02 $和$σ__{s_8} = 0.20 $的附加系统错误。我们通过基于X射线光度函数将聚类约束与codex宇宙学约束结合在一起来说明聚集约束的互补性，从而得出$ω__{M_0} = 0.25 \ pm 0.01 $和$σ_8= 0.81 = 0.81^{+0.01} {+0.01} _ { - 0.02} $ { - 0.02} $σ_{ω_{m_0}} = 0.07 $和$σ_{σ_8} = 0.04 $。质量示踪剂的质量校准和统计质量是不确定性的主要来源。
Aims. We analyze the autocorrelation function of a large contiguous sample of galaxy clusters, the Constrain Dark Energy with X-ray (CODEX) sample, in which we take particular care of cluster definition. These clusters were X-ray selected using the RASS survey and then identified as galaxy clusters using the code redMaPPer run on the photometry of the SDSS. We develop methods for precisely accounting for the sample selection effects on the clustering and demonstrate their robustness using numerical simulations. Methods. Using the clean CODEX sample, which was obtained by applying a redshift-dependent richness selection, we computed the two-point autocorrelation function of galaxy clusters in the $0.1<z<0.3$ and $0.3<z<0.5$ redshift bins. We compared the bias in the measured correlation function with values obtained in numerical simulations using a similar cluster mass range. Results. By fitting a power law, we measured a correlation length $r_0=18.7 \pm 1.1$ and slope $γ=1.98 \pm 0.14$ for the correlation function in the full redshift range. By fixing the other cosmological parameters to their WMAP9 values, we reproduced the observed shape of the correlation function under the following cosmological conditions: $Ω_{m_0}=0.22^{+0.04}_{-0.03}$ and $S_8=σ_8 (Ω_{m_0} /0.3)^{0.5}=0.85^{+0.10}_{-0.08}$ with estimated additional systematic errors of $σ_{Ω_{m_0}} = 0.02$ and $σ_{S_8} = 0.20$. We illustrate the complementarity of clustering constraints by combining them with CODEX cosmological constraints based on the X-ray luminosity function, deriving $Ω_{m_0} = 0.25 \pm 0.01$ and $σ_8 = 0.81^{+0.01}_{-0.02}$ with an estimated additional systematic error of $σ_{Ω_{m_0}} = 0.07$ and $σ_{σ_8} = 0.04$. The mass calibration and statistical quality of the mass tracers are the dominant source of uncertainty.
