Optimizing weak lensing mass estimates for cluster profile uncertainty
Optimizing weak lensing mass estimates for cluster profile uncertainty
复制标题
优化簇轮廓不确定性的弱透镜质量估计
DOI：
10.1111/j.1365-2966.2011.19135.x
复制
发表时间：
2011
影响因子：
4.8
通讯作者：
and S. Seitz
中科院分区：
文献类型：
--
作者：
D. Gruen;G. M. Bernstein;T. Y. Lam;and S. Seitz
星系团质量的弱透镜测量对于校正质量可观测关系（MORs）以研究暗能量的结构和性质的增长是必要的。然而，所测量的星系团剪切信号在固定质量M200 m处变化，这是由于背景星系的固有椭圆率、沿视线沿着的介入结构以及由于浓度、非球面性和子结构的散射而导致的星系团结构的变化。我们使用N体模拟晕来推导和评估弱透镜圆孔质量测量图，该图在所有这些形式的可变性存在的情况下使质量估计方差<（Map− M200 m）2>最小化。根据晕质量和观测条件，由此产生的质量估计提高onMapfilters优化的圆形NFW-配置文件集群中存在的不相关的大尺度结构（LSS），后者改善的估计，只最大限度地减少形状噪声的影响。在忽略内部集群结构变化的同时优化不相关的LSS，会对晕核附近的轮廓施加太多权重，在某些情况下甚至可能比根本不考虑LSS更糟糕。我们简要地讨论了集群结构和相关结构的设计和性能的弱透镜调查旨在校准集群MORs的变化的影响。
Weak lensing measurements of cluster masses are necessary for calibrating mass-observable relations (MORs) to investigate the growth of structure and the properties of dark energy. However, the measured cluster shear signal varies at fixed massM200mdue to inherent ellipticity of background galaxies, intervening structures along the line of sight and variations in the cluster structure due to scatter in concentrations, asphericity and substructure. We useN-body simulated haloes to derive and evaluate a weak lensing circular aperture mass measurementMapthat minimizes the mass estimate variance <(Map−M200m)2> in the presence of all these forms of variability. Depending on halo mass and observational conditions, the resulting mass estimator improves onMapfilters optimized for circular NFW-profile clusters in the presence of uncorrelated large-scale structure (LSS) about as much as the latter improve on an estimator that only minimizes the influence of shape noise. Optimizing for uncorrelated LSS while ignoring the variation of internal cluster structure puts too much weight on the profile near the cores of haloes, and under some circumstances can even be worse than not accounting for LSS at all. We briefly discuss the impact of variability in cluster structure and correlated structures on the design and performance of weak lensing surveys intended to calibrate cluster MORs.