论文标题
6DF Galaxy调查中红移空间扭曲和特殊速度的关节增长率测量
Joint growth rate measurements from redshift-space distortions and peculiar velocities in the 6dF Galaxy Survey
论文作者
论文摘要
我们提出了一个新的模型，用于在星系红移空间扭曲和特殊速度之间进行交叉方案。我们将其与两种探针的自动辅助模型结合在一起，以完全自洽的最大样本方法，使我们能够提取增强的宇宙参数约束。当将我们的方法应用于6度野外星系调查（6DFGS）时，我们对结构增长率的约束为$fσ_8= 0.384 = 0.384 \ pm 0.052 \ rm {（stat）} \ pm 0.061 \ pm 0.061 \ rm {（sys sys）} $，并且我们的限制是$ redshift space space parameter IS $β= 0.289^{+0.044} _ { - 0.043} \ rm {（stat）} \ pm 0.049 \ rm {（sys）} $。我们发现，与使用特殊的速度自动速度自动稳定性模型相比，使用完整的协方差模型相比，使用完整的协方差模型相比，使用完整的协方差模型时，结构增长率的统计不确定性降低了64％。我们的约束与文献中有关大规模结构的多个示踪剂以及其他6DFGS分析的示踪剂的约束是一致的。我们的测量也与标准宇宙学模型一致。
We present a new model for the cross-covariance between galaxy redshift-space distortions and peculiar velocities. We combine this with the auto-covariance models of both probes in a fully self-consistent, maximum-likelihood method, allowing us to extract enhanced cosmological parameter constraints. When applying our method to the 6-degree Field Galaxy Survey (6dFGS), our constraint on the growth rate of structure is $fσ_8 = 0.384 \pm 0.052 \rm{(stat)} \pm 0.061 \rm{(sys)}$ and our constraint for the redshift-space distortion parameter is $β= 0.289^{+0.044}_{-0.043} \rm{(stat)} \pm 0.049 \rm{(sys)}$. We find that the statistical uncertainty for the growth rate of structure is reduced by 64% when using the complete covariance model compared to the redshift-space distortion auto-covariance model and 50% when compared to using the peculiar velocity auto-covariance model. Our constraints are consistent with those from the literature on combining multiple tracers of large-scale structure, as well as those from other 6dFGS analyses. Our measurement is also consistent with the standard cosmological model.
