论文标题
弱透镜偏斜
Weak Lensing Skew-Spectrum
论文作者
论文摘要
我们介绍了偏斜的光谱统计量，以缩小透镜收敛$κ$地图，并针对最先进的高分辨率全天空数值模拟进行测试。 我们执行分析是单个断层扫描的源红移和平滑角度尺度的函数。我们还分析了不同层析成像箱之间的互相关。 我们将数值结果与用于对基础密度场的双光谱建模的拟合功能作为红移和比例的函数。我们得出了重力诱导的次级非高斯性的偏斜光谱的封闭形式表达。 我们还计算了从宇宙微波背景（CMB）研究中推断出的预计$κ$的偏斜光谱。 与低红移案例相比，我们发现出生后的校正在对此类研究的偏斜谱的建模中很重要。我们展示了如何将掩模和噪声的存在纳入偏斜光谱的估计中。
We introduce the skew-spectrum statistic for weak lensing convergence $κ$ maps and test it against state-of-the-art high-resolution all-sky numerical simulations. We perform the analysis as a function of source redshift and smoothing angular scale for individual tomographic bins. We also analyse the cross-correlation between different tomographic bins. We compare the numerical results to fitting-functions used to model the bispectrum of the underlying density field as a function of redshift and scale. We derive a closed form expression for the skew-spectrum for gravity-induced secondary non-Gaussianity. We also compute the skew-spectrum for the projected $κ$ inferred from Cosmic Microwave Background (CMB) studies. As opposed to the low redshift case we find the post-Born corrections to be important in the modelling of the skew-spectrum for such studies. We show how the presence of a mask and noise can be incorporated in the estimation of a skew-spectrum.
