A 2.5% measurement of the growth rate from small-scale redshift space clustering of SDSS-III CMASS galaxies
A 2.5% measurement of the growth rate from small-scale redshift space clustering of SDSS-III CMASS galaxies
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A%202.5%%20测量%20of%20%20增长%20率%20来自%20小规模%20红移%20空间%20聚类%20of%20SDSS-III%20CMASS%20星系
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发表时间：
2014
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通讯作者：
White
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作者：
B. Reid;H. Seo;A. Leauthaud;J. Tinker;Martin;White
我们在~ 0的尺度上对SDSS-III CMASS DR10星系的各向异性群集进行了首次拟合。8−32 h−1 Mpc在最适合普朗克Λ CDM宇宙学附近评估的标准光晕占据分布模型与观测到的各向异性聚类有很好的拟合，并暗示了f σ 8 （z = 0）的M ~ 2 × 10 13 h−1 M （cid:12）光晕的特殊速度场的归一化。57) = 0。450±0。011. 由于这个约束包括准线性和非线性尺度，它应该严格约束在这些尺度上增强成对落体速度的修正重力模型。虽然依赖于模型，但我们的测量结果比大尺度上的DR11分析精度提高了2.5倍，f σ 8 (z = 0。57) = 0。447±0。这是迄今为止对宇宙结构增长率最严格的单一约束。我们的测量结果与普朗克Λ CDM预测的0一致。480±0。010在~ 1。9 σ电平。假设一个最适合普朗克宇宙学的光晕质量函数，我们还发现10%的CMASS星系是质量为M ~ 6 × 10 13 h−1 M （cid:12）的光晕中的卫星。虽然我们的测试和模型推广都没有指出由于星系-晕连接的模型不够详细而导致的系统误差，但这些初步结果的精度值得进一步研究模型的不确定性和宇宙参数的简并。在相对较小的距离(~ 0。8−32 h−1 Mpc)和Λ CDM背景下标准光晕模型的预测。我们发现我们的简化的、红移无关的HOD模型与我们的
We perform the first fit to the anisotropic clustering of SDSS-III CMASS DR10 galaxies on scales of ∼ 0 . 8 − 32 h − 1 Mpc. A standard halo occupation distribution model evaluated near the best fit Planck Λ CDM cosmology provides a good fit to the observed anisotropic clustering, and implies a normalization for the peculiar velocity field of M ∼ 2 × 10 13 h − 1 M (cid:12) halos of f σ 8 ( z = 0 . 57) = 0 . 450 ± 0 . 011. Since this constraint includes both quasi-linear and non-linear scales, it should severely constrain modified gravity models that enhance pairwise infall velocities on these scales. Though model dependent, our measurement represents a factor of 2.5 improvement in precision over the analysis of DR11 on large scales, f σ 8 ( z = 0 . 57) = 0 . 447 ± 0 . 028, and is the tightest single constraint on the growth rate of cosmic structure to date. Our measurement is consistent with the Planck Λ CDM prediction of 0 . 480 ± 0 . 010 at the ∼ 1 . 9 σ level. Assuming a halo mass function evaluated at the best fit Planck cosmology, we also find that 10% of CMASS galaxies are satellites in halos of mass M ∼ 6 × 10 13 h − 1 M (cid:12) . While none of our tests and model generalizations indicate systematic errors due to an insufficiently detailed model of the galaxy-halo connection, the precision of these first results warrant further investigation into the modeling uncertainties and degeneracies with cosmological parameters. clustering of galaxies at relatively small separations ( ∼ 0 . 8 − 32 h − 1 Mpc) and the predictions of a standard halo model in the context of Λ CDM. We found good agreement between our simplified, redshift-independent HOD model and our