Lensing reconstruction from a patchwork of polarization maps
Lensing reconstruction from a patchwork of polarization maps
复制标题
从偏振图拼凑而成的透镜重建
DOI：
10.1088/1475-7516/2014/09/009
复制
发表时间：
2014
影响因子：
6.4
通讯作者：
Ryo Nagata
中科院分区：
文献类型：
--
作者：
Toshiya Namikawa;Ryo Nagata
CMB偏振图中涉及的透镜信号已经用SPTpol和POLARBEAR等地面实验进行了测量，并将在不久的将来成为宇宙学和天体物理学问题的重要探测器。然而，来自地面实验的偏振图的大小受到观测噪声的长波长模式的污染的限制。为了进一步提取的透镜信号，我们探索的可行性，测量透镜信号从收集的小天空地图，其中每一个单独观察的地面大型望远镜，即，从拼凑的大天空覆盖范围的小天空补丁组织的地图透镜重建。我们表明，虽然从拼接图获得的B模式功率谱是有偏见的，由于基线的不确定性，偏置的透镜势将是可以忽略不计的，如果B模式的尺度大于爆破规模的1/f噪声被删除在透镜重建。作为宇宙学应用的例子，我们还展示了1）重建的透镜势和全天空温度/偏振图之间的互相关，从卫星任务，如普朗克和LiteBIRD，和2）使用重建的潜在的LiteBIRD观测的B模式偏振去透镜。
The lensing signals involved in CMB polarization maps have already been measured with ground-based experiments such as SPTpol and POLARBEAR, and would become important as a probe of cosmological and astrophysical issues in the near future. Sizes of polarization maps from ground-based experiments are, however, limited by contamination of long wavelength modes of observational noise. To further extract the lensing signals, we explore feasibility of measuring lensing signals from a collection of small sky maps each of which is observed separately by a ground-based large telescope, ie, lensing reconstruction from a patchwork map of large sky coverage organized from small sky patches. We show that, although the B-mode power spectrum obtained from the patchwork map is biased due to baseline uncertainty, bias on the lensing potential would be negligible if the B-mode on scales larger than the blowup scale of 1/f noise is removed in the lensing reconstruction. As examples of cosmological applications, we also show 1) the cross-correlations between the reconstructed lensing potential and full-sky temperature/polarization maps from satellite missions such as PLANCK and LiteBIRD, and 2) the use of the reconstructed potential for delensing B-mode polarization of LiteBIRD observation.