Optimal filtering for CMB lensing reconstruction
Optimal filtering for CMB lensing reconstruction
复制标题
CMB 透镜重建的最优滤波
DOI：
10.1103/physrevd.100.123509
复制
发表时间：
2019
影响因子：
5
通讯作者：
A. Lewis
中科院分区：
文献类型：
--
作者：
M. Mirmelstein;J. Carron;A. Lewis
即将进行的地基宇宙微波背景实验将提供具有高灵敏度和高分辨率的宇宙微波背景图，可用于高保真透镜重建。然而，天空覆盖将是不完整的，噪声高度各向异性，所以需要优化的估计器从地图中提取最多的信息。我们专注于基于二次估计的透镜重建方法，快速实现，并比较新的更优化的过滤估计与各种估计，以前曾在文献中使用。可以使用共轭梯度（或其他）技术对输入CMB图进行最佳逆信号加噪声滤波，以考虑噪声各向异性。然而，从这些滤波的输入图的透镜化重建具有对透镜化信号的各向异性响应，并且难以直接解释。我们描述了一个第二阶段过滤的透镜映射和解析响应模型，可以用来构建透镜功率谱估计，占各向异性响应和噪声不均匀性在近似最佳的方式，同时保持快速计算。我们比较了即将到来的西蒙斯天文台和CMB第4阶段实验的模拟结果，以显示更优化的透镜重建管道的鲁棒性，并量化了与不太优化的估计器相比的改进。我们发现一个显着的改善，在重建的透镜功率方差最佳各向异性和各向同性滤波的CMB地图之间，和高达30%的改善方差通过使用额外的过滤步骤的重建电位图。我们的近似解析响应模型是无偏的，在一个小的10-水平的额外的Monte Carlo校正。
Upcoming ground-based cosmic microwave background experiments will provide CMB maps with high sensitivity and resolution that can be used for high fidelity lensing reconstruction. However, the sky coverage will be incomplete and the noise highly anisotropic, so optimized estimators are required to extract the most information from the maps. We focus on quadratic-estimator based lensing reconstruction methods that are fast to implement, and compare new more-optimally filtered estimators with various estimators that have previously been used in the literature. Input CMB maps can be optimally inverse-signal-plus-noise filtered using conjugate gradient (or other) techniques to account for the noise anisotropy. However, lensing reconstructions from these filtered input maps have an anisotropic response to the lensing signal and are difficult to interpret directly. We describe a second-stage filtering of the lensing maps and analytic response model that can be used to construct lensing power spectrum estimates that account for the anisotropic response and noise inhomogeneity in an approximately optimal way while remaining fast to compute. We compare results for simulations of upcoming Simons Observatory and CMB Stage-4 experiments to show the robustness of the more optimal lensing reconstruction pipeline and quantify the improvement compared to less optimal estimators. We find a substantial improvement in reconstructed lensing power variance between optimal anisotropic and isotropic filtering of CMB maps, and up to 30% improvement in variance by using the additional filtering step on the reconstruction potential map. Our approximate analytic response model is unbiased to within a small percent-level additional Monte Carlo correction.
智利下一代 CMB 调查策略设计
DOI：
10.1117/12.2313898
发表时间：
2018
期刊：
--
影响因子：
--
作者：
Zhu N
通讯作者：
Zhu N
DOI：
10.2172/1352047
发表时间：
2016-10
期刊：
--
影响因子：
--
作者：
K. Abazajian;Peter Adshead;Z. Ahmed;S. Allen;D. Alonso;K. Arnold;C. Baccigalupi;J. Bartlett;
通讯作者：
K. Abazajian;Peter Adshead;Z. Ahmed;S. Allen;D. Alonso;K. Arnold;C. Baccigalupi;J. Bartlett;
西蒙斯天文台
DOI：
10.48550/arxiv.1907.08284
发表时间：
2019
期刊：
Bulletin of the American Astronomical Society
影响因子：
--
作者：
Lee Adrian
通讯作者：
Lee Adrian