Dark Energy Survey Year 3 results: Cosmology from cosmic shear and robustness to data calibration
Dark Energy Survey Year 3 results: Cosmology from cosmic shear and robustness to data calibration
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DOI：
10.1103/physrevd.105.023514
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发表时间：
2022-01-13
影响因子：
5
通讯作者：
Weller, J.
中科院分区：
文献类型：
--
作者：
Amon, A.;Gruen, D.;Weller, J.
这项工作，连同它的同伴论文，Secco， Samuroff等人。Rev. D 105,023515(2022)]，介绍了暗能量调查第三年的宇宙剪切测量和基于对超过1亿个源星系的分析的宇宙学约束。数据跨越4143度(2)的天空，分为四个红移箱，我们产生了一个测量与40的信噪比。我们在Lambda-冷暗物质（Lambda CDM）模型的背景下进行了盲分析，发现聚类振幅有3%的约束，S-8 sigma(8)(Omega(m)/0.3)(0.5) = 0.759(-0.023)（+0.025）。Lambda cdm优化分析安全地包含了较小尺度的信息，得到了2%的精度测量值S-8 = 0.772(-0.017)(+0.018)，与基准情况一致。两次低红移测量结果与普朗克宇宙微波背景结果在统计上是一致的，但是，两次恢复的S-8值分别比高红移预测值低2.3 sigma和2.1 sigma （p值分别为0.02和0.05）。测量结果显示在红移箱、角尺度和相关函数之间是内部一致的。当红移校准样本的选择、红移不确定性的建模和方法不同时，S-8后检结果一致，证明了该分析对校准系统具有鲁棒性。同样地，我们发现，为了解释星系混合而包含的修正将我们最适合的S-8偏移了0.5西格玛，而不会导致不确定性的大幅增加。我们考察了宇宙学约束精度的限制因素，并发现观测系统学在天体物理学建模中是次要的。具体地说，我们确定了模拟重子效应和内禀排列的不确定性作为限制系统学。
This work, together with its companion paper, Secco, Samuroff et al. [Phys. Rev. D 105, 023515 (2022)], present the Dark Energy Survey Year 3 cosmic-shear measurements and cosmological constraints based on an analysis of over 100 million source galaxies. With the data spanning 4143 deg(2) on the sky, divided into four redshift bins, we produce a measurement with a signal-to-noise of 40. We conduct a blind analysis in the context of the Lambda-Cold Dark Matter (Lambda CDM) model and find a 3% constraint of the clustering amplitude, S-8 sigma(8)(Omega(m)/0.3)(0.5) = 0.759(-0.023)(+0.025). A Lambda CDM-Optimized analysis, which safely includes smaller scale information, yields a 2% precision measurement of S-8 = 0.772(-0.017)(+0.018) that is consistent with the fiducial case. The two low-redshift measurements are statistically consistent with the Planck Cosmic Microwave Background result, however, both recovered S-8 values are lower than the high-redshift prediction by 2.3 sigma and 2.1 sigma (p-values of 0.02 and 0.05), respectively. The measurements are shown to be internally consistent across redshift bins, angular scales and correlation functions. The analysis is demonstrated to be robust to calibration systematics, with the S-8 posterior consistent when varying the choice of redshift calibration sample, the modeling of redshift uncertainty and methodology. Similarly, we find that the corrections included to account for the blending of galaxies shifts our best-fit S-8 by 0.5 sigma without incurring a substantial increase in uncertainty. We examine the limiting factors for the precision of the cosmological constraints and find observational systematics to be subdominant to the modeling of astrophysics. Specifically, we identify the uncertainties in modeling baryonic effects and intrinsic alignments as the limiting systematics.