The VIMOS Public Extragalactic Redshift Survey (VIPERS) O m 0 from the galaxy clustering ratio measured at z ~ 1?
The VIMOS Public Extragalactic Redshift Survey (VIPERS) O m 0 from the galaxy clustering ratio measured at z ~ 1?
复制标题
VIMOS 公共河外红移巡天 (VIPERS) O m 0 从 z ~ 1 处测得的星系簇比？
DOI：
10.1051/0004-6361/201321942
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发表时间：
2014
影响因子：
6.5
通讯作者：
Bel J
中科院分区：
文献类型：
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作者：
Bel J
我们使用 VIMOS 公共河外红移巡天 (VIPERS) 公共数据发布 1 (PDR-1) 目录中约 22 000 个 0.65 <z< 1.2 星系的样本，通过测量星系团簇比率 ηg,R 来约束宇宙学模型。该统计量具有有利的属性，其定义为表征给定半径 R 的球体中平滑密度场的两个量的比率：其相关函数在此尺度倍数上的值 xi(nR) 及其方差 σ2(R)。对于足够大的 R 值，这是一个通用数，它捕获独立于特定星系示踪剂的线性偏差和线性红移空间扭曲的 2 点聚类信息。在本文中，我们详细讨论了如何将 ηg,R 的应用扩展到准线性尺度，以及如何控制和消除观测选择效应，这是 VIPERS 等红移巡天的典型特征。我们使用与调查选择过程相匹配的模拟目录来验证这些程序的准确性和效率。这些结果显示了 ηg,R 对非线性和观测效应的鲁棒性，这与其定义为受到类似影响的数量之比有关。在有效红移 z = 0.93 时，我们在 R= 5h-1Mpc 时测量了值 ηg,R(15) = 0.141 ± 0.013。在平坦的 ΛCDM 宇宙学中，通过包含 H0,ns 和重子密度的最佳可用先验，我们获得了当前历元的物质密度参数 Ωm,0= 0.270-0.025+0.029。除了我们使用 VIPERS PDR-1 对 Ω 进行估计时取得了很高的精度之外，这个结果也很引人注目，因为它似乎与最近的估计 atz≃ 0.3 非常一致，这是通过将相同的技术应用于 SDSS-LRG 目录而获得的。因此，它支持当前分析的稳健性。此外，这两个测量值 atz~ 0.3 和 z~ 0.9 的结合为我们提供了 Ωm,0= 0.274 ± 0.017 的非常精确的估计，这凸显了我们的估计与其他宇宙学探测器（例如重子声振荡、宇宙微波背景和超新星）之间的高度一致性。
We use a sample of about 22 000 galaxies at 0.65 <z< 1.2 from the VIMOS Public Extragalactic Redshift Survey (VIPERS) Public Data Release 1 (PDR-1) catalogue, to constrain the cosmological model through a measurement of the galaxyclustering ratioηg,R. This statistic has favourable properties, which is defined as the ratio of two quantities characterizing the smoothed density field in spheres of a given radiusR: the value of its correlation function on a multiple of this scale,ξ(nR), and its varianceσ2(R). For sufficiently large values ofR, this is a universal number, which captures 2-point clustering information independently of the linear bias and linear redshift-space distortions of the specific galaxy tracers. In this paper, we discuss how to extend the application ofηg,Rto quasi-linear scales and how to control and remove observational selection effects, which are typical of redshift surveys as VIPERS, in detail. We verify the accuracy and efficiency of these procedures using mock catalogues that match the survey selection process. These results show the robustness ofηg,Rto non-linearities and observational effects, which is related to its very definition as a ratio of quantities that are similarly affected. At an effective redshiftz= 0.93, we measured the valueηg,R(15) = 0.141 ± 0.013 atR= 5h-1Mpc. Within a flat ΛCDM cosmology and by including the best available priors onH0,nsand baryon density, we obtain a matter density parameter at the current epoch Ωm,0= 0.270-0.025+0.029. In addition to the great precision achieved on our estimation of Ωmusing VIPERS PDR-1, this result is remarkable because it appears to be in good agreement with a recent estimate atz≃ 0.3, which was obtained by applying the same technique to the SDSS-LRG catalogue. It, therefore, supports the robustness of the present analysis. Moreover, the combination of these two measurements atz~ 0.3 andz~ 0.9 provides us with a very precise estimate of Ωm,0= 0.274 ± 0.017, which highlights the great consistency between our estimation and other cosmological probes, such as baryonic acoustic oscillations, cosmic microwave background, and supernovae.