The 6dF Galaxy Survey: cosmological constraints from the velocity power spectrum
The 6dF Galaxy Survey: cosmological constraints from the velocity power spectrum
复制标题
DOI：
10.1093/mnras/stu1615
复制
发表时间：
2014-11
影响因子：
4.8
通讯作者：
Andrew Johnson;C. Blake;J. Koda;Yin-Zhe Ma;M. Colless;M. Crocce;T. Davis;D. H. Jones;D. H. Jones;C. Magoulas;C. Magoulas;C. Magoulas;J. Lucey;J. Mould;Morag I. Scrimgeour;Morag I. Scrimgeour;C. Springob;C. Springob
中科院分区：
文献类型：
--
作者：
Andrew Johnson;C. Blake;J. Koda;Yin-Zhe Ma;M. Colless;M. Crocce;T. Davis;D. H. Jones;D. H. Jones;C. Magoulas;C. Magoulas;C. Magoulas;J. Lucey;J. Mould;Morag I. Scrimgeour;Morag I. Scrimgeour;C. Springob;C. Springob
我们提出了尺度依赖的测量的归一化增长率的结构f σ 8（k，z = 0）只使用特殊的运动的星系。我们使用6度场星系巡天速度样本的数据，以及一个新编制的低红移样本（z 300 h（-1）Mpc，这是迄今为止最大规模的增长率测量之一。我们没有发现证据的规模依赖的增长率，或任何统计上显着的变化，从普朗克宇宙学预测的增长率。把所有的尺度在一起，我们确定的归一化增长率在z = 0类似于15%的方式独立的星系偏差和良好的协议的约束，从测量红移空间扭曲6度场星系调查。我们特别注意系统误差。我们指出，本征散射存在于基本平面和塔利-费舍尔关系是高斯对数距离单位，错误地假设它是高斯线性（速度）单位可以偏见宇宙学约束。我们还分析边缘化的零点误差的距离指标，验证我们所有的约束，使用数值模拟的准确性，并演示了如何结合联合收割机不同的（相关）速度调查使用矩阵“超参数”分析。目前和即将到来的奇特速度调查将使我们能够详细了解低红移宇宙中结构的增长，对暗能量的性质提供强有力的约束。
We present scale-dependent measurements of the normalized growth rate of structure f sigma 8(k, z = 0) using only the peculiar motions of galaxies. We use data from the 6-degree Field Galaxy Survey velocity sample together with a newly compiled sample of low-redshift (z 300 h(-1) Mpc, which represents one of the largest scale growth rate measurement to date. We find no evidence for a scale-dependence in the growth rate, or any statistically significant variation from the growth rate as predicted by the Planck cosmology. Bringing all the scales together, we determine the normalized growth rate at z = 0 to similar to 15 per cent in a manner independent of galaxy bias and in excellent agreement with the constraint from the measurements of redshift-space distortions from 6-degree Field Galaxy Survey. We pay particular attention to systematic errors. We point out that the intrinsic scatter present in Fundamental Plane and Tully-Fisher relations is only Gaussian in logarithmic distance units; wrongly assuming it is Gaussian in linear (velocity) units can bias cosmological constraints. We also analytically marginalize over zero-point errors in distance indicators, validate the accuracy of all our constraints using numerical simulations, and demonstrate how to combine different (correlated) velocity surveys using a matrix 'hyperparameter' analysis. Current and forthcoming peculiar velocity surveys will allow us to understand in detail the growth of structure in the low-redshift universe, providing strong constraints on the nature of dark energy.