论文标题
黑暗能源调查1年结果：群集丰度和镜头弱的宇宙学限制
Dark Energy Survey Year 1 Results: Cosmological Constraints from Cluster Abundances and Weak Lensing
论文作者
论文摘要
我们对从黑暗能源调查（DES）1年数据集中选择的Redmapper簇的计数和弱透镜信号进行联合分析。我们的分析使用与DES组合探针分析相同的剪切和源光度红移估计值。我们的分析导致$ S_8 =σ_8（ω_ {\ rm M} /0.3）的值令人惊讶地低值$σ_8-ω_ {\ rm m} $ postteriors $2.4σ$张力，带有des y1 3x2pt结果，以及$5.6σ$，以及Planck CMB分析。这些结果包括对分析后无盲的变化的影响，与未闪烁时获得的结果相比，这并不能提高与其他数据集的一致性。多个宇宙学探针（超新星，巴属声学振荡，宇宙剪切，星系聚类和CMB各向异性）以及其他星系簇分析的事实都显着较高，这都显着较高的物质密度表明数据中存在系统错误的数据或相关物理学的不满模型。使用X射线和微波数据进行交叉检查，以及对SZ选定簇的可观察到的 - 质量关系的独立约束，这表明差异驻留在我们对弱透镜信号的建模中，而不是集群丰度。使用更高的丰富度阈值（$λ\ ge 30 $）重复我们的分析可显着降低使用其他探针的张力，并指向我们模型未捕获的一个或多个依赖性依赖性效应。
We perform a joint analysis of the counts and weak lensing signal of redMaPPer clusters selected from the Dark Energy Survey (DES) Year 1 dataset. Our analysis uses the same shear and source photometric redshifts estimates as were used in the DES combined probes analysis. Our analysis results in surprisingly low values for $S_8 =σ_8(Ω_{\rm m}/0.3)^{0.5}= 0.65\pm 0.04$, driven by a low matter density parameter, $Ω_{\rm m}=0.179^{+0.031}_{-0.038}$, with $σ_8-Ω_{\rm m}$ posteriors in $2.4σ$ tension with the DES Y1 3x2pt results, and in $5.6σ$ with the Planck CMB analysis. These results include the impact of post-unblinding changes to the analysis, which did not improve the level of consistency with other data sets compared to the results obtained at the unblinding. The fact that multiple cosmological probes (supernovae, baryon acoustic oscillations, cosmic shear, galaxy clustering and CMB anisotropies), and other galaxy cluster analyses all favor significantly higher matter densities suggests the presence of systematic errors in the data or an incomplete modeling of the relevant physics. Cross checks with X-ray and microwave data, as well as independent constraints on the observable--mass relation from SZ selected clusters, suggest that the discrepancy resides in our modeling of the weak lensing signal rather than the cluster abundance. Repeating our analysis using a higher richness threshold ($λ\ge 30$) significantly reduces the tension with other probes, and points to one or more richness-dependent effects not captured by our model.
