arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2007.03150astro-ph.CO
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用标记加权关联函数改进对宇宙学参数的约束

Using the Mark Weighted Correlation Functions to Improve the Constraints on Cosmological Parameters

Yizhao Yang, Haitao Miao, Qinglin Ma, Miaoxin Liu, Cristiano G. Sabiu, Jaime Forero-Romero, Yuanzhu Huang, Limin Lai, Qiyue Qian, Yi Zheng, Xiao-Dong Li

摘要:

我们使用标记加权关联函数(MCFs)$W(s)$来研究宇宙的大尺度结构。我们研究了五种类型的MCF加权方案$ρ^α$,其中$ρ$是局部密度,$α$被视为$-1,\ -0.5,\ 0,\ 0.5$,和1。我们发现,不同的MCF有非常不同的幅度和尺度依赖性。一些MCF表现出在标准关联函数中不存在的独特的峰和谷。它们的位置相对于红移和背景几何是稳健的,但是它们不太可能被用作探测宇宙膨胀历史的“标准规则”。尽管如此,我们发现这些特征可以用来探测与结构形成历史相关的参数,如$σ_8$值和星系偏差。最后,利用$W(s)$和$W_{Δs}(μ)$的完整形状进行综合分析后,我们发现,结合不同类型的MCF可以显著改善宇宙学参数约束。与仅使用标准相关函数相比,MCF与$α=0,\ 0.5,\ 1$和$α=0,\ -1,\ -0.5,\ 0.5,\ 1$的组合可以分别通过$\approx30\%$和$50\%$来改善对$Ω_m$和$w$的约束。我们发现非常重要的证据表明,MCFs可以改善宇宙学参数的约束。

英文摘要:

We used the mark weighted correlation functions (MCFs), $W(s)$, to study the large scale structure of the Universe. We studied five types of MCFs with the weighting scheme $ρ^α$, where $ρ$ is the local density, and $α$ is taken as $-1,\ -0.5,\ 0,\ 0.5$, and 1. We found that different MCFs have very different amplitudes and scale-dependence. Some of the MCFs exhibit distinctive peaks and valleys that do not exist in the standard correlation functions. Their locations are robust against the redshifts and the background geometry, however it is unlikely that they can be used as ``standard rulers'' to probe the cosmic expansion history. Nonetheless we find that these features may be used to probe parameters related with the structure formation history, such as the values of $σ_8$ and the galaxy bias. Finally, after conducting a comprehensive analysis using the full shapes of the $W(s)$s and $W_{Δs}(μ)$s, we found that, combining different types of MCFs can significantly improve the cosmological parameter constraints. Compared with using only the standard correlation function, the combinations of MCFs with $α=0,\ 0.5,\ 1$ and $α=0,\ -1,\ -0.5,\ 0.5,\ 1$ can improve the constraints on $Ω_m$ and $w$ by $\approx30\%$ and $50\%$, respectively. We find highly significant evidence that MCFs can improve cosmological parameter constraints.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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