论文标题

来自大规模聚类的傅立叶和配置空间的大规模聚类的联合分析的重气声振荡

Baryon acoustic oscillations from a joint analysis of the large-scale clustering in Fourier and configuration space

论文作者

Dumerchat, Tyann, Bautista, Julian E.

论文摘要

Baryon声学振荡(BAOS)是对我们宇宙扩展历史的强大探针,通常在Galaxy调查的两点统计中测量,无论是在傅立叶空间还是在配置空间中。在这项工作中,我们报告了从功率谱和相关功能多物的关节拟合中对BAO进行的首次测量。我们使用一组1000个模拟目录测试了我们的新框架,并表明我们的方法比单独拟合功率谱或相关函数或将它们与高斯近似方法相结合时,对BAO参数产生的偏差较小。我们的估计不确定性略大于高斯近似值的不确定性,这可能是由于我们的样品协方差矩阵中的噪声,较大的滋扰参数,或者我们的新框架不依赖于BAO参数的高斯可能性的假设。但是,我们认为我们的不确定性更为可靠,因为它们依赖于更少的假设,并且由于我们的方法在两点统计级别的傅立叶和配置空间之间存在相关性。 We performed a joint analysis of the luminous red galaxy sample of the extended baryon oscillation spectroscopic survey (eBOSS) data release 16, obtaining $D_H/r_d = 19.27 \pm 0.48$ and $D_M/r_d = 17.77 \pm 0.37$, in excellent agreement with the official eBOSS consensus BAO-only results $D_H/r_d = 19.33 \pm 0.53 $和$ d_m/r_d = 17.86 \ pm 0.33 $。

Baryon acoustic oscillations (BAOs) are a powerful probe of the expansion history of our Universe and are typically measured in the two-point statistics of a galaxy survey, either in Fourier space or in configuration space. In this work, we report a first measurement of BAOs from a joint fit of power spectrum and correlation function multipoles. We tested our new framework with a set of 1000 mock catalogs and showed that our method yields smaller biases on BAO parameters than individually fitting power spectra or correlation functions, or when combining them with the Gaussian approximation method. Our estimated uncertainties are slightly larger than those from the Gaussian approximation, likely due to noise in our sample covariance matrix, the larger number of nuisance parameters, or the fact that our new framework does not rely on the assumption of Gaussian likelihoods for the BAO parameters. However, we argue that our uncertainties are more reliable since they rely on fewer assumptions, and because our method takes correlations between Fourier and configuration space at the level of the two-point statistics. We performed a joint analysis of the luminous red galaxy sample of the extended baryon oscillation spectroscopic survey (eBOSS) data release 16, obtaining $D_H/r_d = 19.27 \pm 0.48$ and $D_M/r_d = 17.77 \pm 0.37$, in excellent agreement with the official eBOSS consensus BAO-only results $D_H/r_d = 19.33 \pm 0.53$ and $D_M/r_d =17.86 \pm 0.33$.

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