论文标题

黑暗能源调查中的星系聚类中的线性系统缓解措施第1年数据

Linear Systematics Mitigation in Galaxy Clustering in the Dark Energy Survey Year 1 Data

论文作者

Wagoner, Erika L., Rozo, Eduardo, Fang, Xiao, Crocce, Martín, Elvin-Poole, Jack, Weaverdyck, Noah

论文摘要

我们实施了一个线性模型来减轻星系聚类分析中观察条件和其他污染源的影响。我们的治疗方法改善了对深色能源调查(DES)1(Y1)宇宙学分析的基准系统治疗的改善。具体而言,我们的治疗方法:1)不需要决定可观察到的系统具有重要意义的决定性,允许多个地图的可能性相干地增加,即使没有单个地图本身会产生重大偏见,也会产生显着的偏见; 2)在缓解程序中同时表征统计和系统的不确定性,使我们能够将不确定性传播到报告的宇宙学约束中; 3)明确利用银河密度场的完整空间结构,以区分星系密度场内的宇宙学和系统的波动; 4)是完全自动化的,因此可以琐碎地应用于任何数据集。 DES Y1红色目录的更新相关函数最小化了该分析的宇宙后代。令人鼓舞的是,我们的分析确实提高了DES Y1 3 $ \ times $ 2PT数据集​​的拟合统计量($Δχ^2 = -6.5 $,没有其他参数)。这种改进几乎是由于相关函数的变化以及与我们的方法相关的附加统计和系统不确定性的变化。我们期望随着宇宙数据集的规模不断增长,缓解技术的差异在将来的工作中变得更加重要。

We implement a linear model for mitigating the effect of observing conditions and other sources of contamination in galaxy clustering analyses. Our treatment improves upon the fiducial systematics treatment of the Dark Energy Survey (DES) Year 1 (Y1) cosmology analysis in four crucial ways. Specifically, our treatment: 1) does not require decisions as to which observable systematics are significant and which are not, allowing for the possibility of multiple maps adding coherently to give rise to significant bias even if no single map leads to a significant bias by itself; 2) characterizes both the statistical and systematic uncertainty in our mitigation procedure, allowing us to propagate said uncertainties into the reported cosmological constraints; 3) explicitly exploits the full spatial structure of the galaxy density field to differentiate between cosmology-sourced and systematics-sourced fluctuations within the galaxy density field; 4) is fully automated, and can therefore be trivially applied to any data set. The updated correlation function for the DES Y1 redMaGiC catalog minimally impacts the cosmological posteriors from that analysis. Encouragingly, our analysis does improve the goodness of fit statistic of the DES Y1 3$\times$2pt data set ($Δχ^2 = -6.5$ with no additional parameters). This improvement is due in nearly equal parts to both the change in the correlation function and the added statistical and systematic uncertainties associated with our method. We expect the difference in mitigation techniques to become more important in future work as the size of cosmological data sets grows.

扫码加入交流群

加入微信交流群

微信交流群二维码

扫码加入学术交流群,获取更多资源