Detection of cosmic magnification via galaxy shear-galaxy number density correlation from HSC survey data
Detection of cosmic magnification via galaxy shear-galaxy number density correlation from HSC survey data
复制标题
通过 HSC 巡天数据中的星系剪切-星系数密度相关性检测宇宙放大率
DOI：
10.1103/physrevd.103.123504
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发表时间：
2021
影响因子：
5
通讯作者：
Fan Zuhui
中科院分区：
文献类型：
--
作者：
Liu Xiangkun;Liu Dezi;Gao Zucheng;Wei Chengliang;Li Guoliang;Fu Liping;Futamase Toshifumi;Fan Zuhui
我们提出了一种新的方法来检测宇宙放大信号的交叉相关的前景收敛领域构建的星系剪切测量与背景星系的位置分布，即剪切数密度相关。我们将其应用于超级Suprime-Cam斯巴鲁战略计划（HSC-SSP）的调查数据。用27个非独立的数据点和它们的全协方差，相对于零和宇宙模型，用Hamanaet al. [Publ. Astron. Soc. Jpn. 72，16（2020）PASJAC0004-626410.1093/pasj/psz138]。两者的贝叶斯因子假设零和HSC宇宙学的模型概率相等，显示出放大信号的清晰检测。从理论上讲，剪切数密度和剪切相关性的比值可以提供一个约束的有效乘法剪切偏置使用内部数据本身。我们用HSC-SSP模拟仿真的信号证明了这一想法，并将统计不确定性重新调整为调查。对于双箱分析与背景星系亮，合并分析导致预测的约束，2.3倍，比单独使用剪切-剪切相关时发现更紧。相应地，随着时间的推移，这一政策也越来越严格。重要的是，联合约束几乎与宇宙学参数无关。因此，我们的研究指出了在弱透镜分析中包括剪切数密度相关的重要性，这可以提供有价值的观测数据的一致性检验，从而巩固导出的宇宙学约束。
We propose a novel method to detect cosmic magnification signals by cross-correlating foreground convergence fields constructed from galaxy shear measurements with background galaxy positional distributions—namely,shear-number densitycorrelation. We apply it to the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) survey data. With 27 nonindependent data points and their full covariance,andwith respect to the null and the cosmological model with the parameters from HSC shear correlation analyses in Hamanaet al.[Publ. Astron. Soc. Jpn. 72, 16 (2020)PASJAC0004-626410.1093/pasj/psz138], respectively. The Bayes factor of the two isassuming equal model probabilities of null and HSC cosmology, showing a clear detection of the magnification signals. Theoretically, the ratio of the shear-number density and shear-shear correlations can provide a constraint on the effective multiplicative shear biasusing internal data themselves. We demonstrate the idea with the signals from our HSC-SSP mock simulations and rescale the statistical uncertainties to a survey of. For two-bin analyses with background galaxies brighter than, the combined analyses lead to a forecasted constraint of, 2.3 times tighter than that found when using the shear-shear correlation alone. Correspondingly,withis tightened bytimes. Importantly, the joint constraint onis nearly independent of cosmological parameters. Our study therefore points to the importance of including the shear-number density correlation in weak lensing analyses, which can provide valuable consistency tests of observational data, and thus to solidify the derived cosmological constraints.