发表机构
Université Paris-Saclay, Université Paris Cité, CEA, CNRS, AIM; Université Paris-Saclay, CEA, IRFU（巴黎萨克雷大学、巴黎西岱大学、法国原子能与替代能源委员会、法国国家科学研究中心、天体物理学与仪器研究所; 巴黎萨克雷大学、法国原子能与替代能源委员会、核物理研究所）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究构建星系团二维约化剪切场正向模型，结合模拟推断，同时估计质量、浓度、椭圆率和中心偏移，质量约束改进达20%，并揭示忽略视线结构会低估质量不确定性。
AI 中文摘要
星系团引起的弱引力透镜效应使得约束其暗物质分布成为可能。通常，弱透镜质量估计通过将二维剪切场压缩为一维来进行。在本工作中，我们构建了星系团周围二维约化剪切场的正向模型，包括来自N体模拟的非高斯相关大尺度结构、不相关的视线方向结构、星系团中心偏移和椭圆率。然后，我们使用基于模拟的推断从完整场中获得星系团质量、浓度、中心偏移和椭圆率的后验分布。二维方法使星系团质量约束改进高达20%。我们表明，这是由于对剪切场中空间相关噪声的更好处理。星系团浓度和中心偏移的估计也有显著改进。虽然星系团椭圆率的估计也有所改进，但对于这些单个星系团约束，约束仍然依赖于先验。我们还量化了视线方向结构对约束的影响。忽略它会使最大质量星系团的质量不确定性低估达2倍。
英文摘要
The effects of weak gravitational lensing induced by clusters of galaxies makes it possible to constrain their dark matter distribution. In general mass estimates from weak lensing are made by compressing the two-dimensional shear-field into one-dimension. In this work we build a forward model of the two-dimensional reduced-shear field around a galaxy cluster, including the non-Gaussian correlated large-scale structure from N-body simulations, the uncorrelated line-of-sight structure, cluster miscentering and ellipticity. We then use simulation-based inference to obtain posteriors on the cluster mass, concentration, miscentering and ellipticity from the full field. The two-dimensional approach leads to improvements on cluster mass constraints by up to 20\%. We show that this is due to a better treatment of the spatially correlated noise across the shear field. There is also significant improvements on the cluster concentration and miscentering. Whilst improvements are also made to the estimation of cluster ellipticity, the constraints are still prior dependent for these individual cluster constraints. We also quantify the impact of the line-of-sight structure on the constraints. Neglecting it underestimates the mass uncertainty by up to a factor of $2$ for the most massive clusters.
Comments14 pages, 12 figures
