论文标题
从宽带观测值重建多色图的最佳方法，具有不对称天线图案
Optimal method for reconstructing polychromatic maps from broadband observations with an asymmetric antenna pattern
论文作者
论文摘要
从具有波长依赖性的，不对称束图案的望远镜获得的宽带时间订购的数据可用于从单个扫描中提取多个波长的地图。当收集有关宇宙现象（例如宇宙微波背景（CMB）辐射）的数据时，该技术特别有用，因为它提供了将CMB信号与前景污染物分开的能力。我们开发了一种方法，以确定可以针对给定望远镜设计重建波长（``颜色''）的最佳线性组合，以及具有高信噪比的可测量的颜色数量。最佳颜色是从反向噪声协方差矩阵得出的基质的特征向量。当望远镜能够在各向同性的情况下扫描天空时，转换为球形谐波基础很有用，在该基础上，该矩阵具有特别简单的形式。我们建议使用从各向同性情况下确定的最佳颜色，即使实际的扫描模式不是各向同性的（例如，仅覆盖天空的一部分）。我们执行模拟，以表明可以从全身和部分天空扫描中准确地重建多种颜色的地图。尽管这项研究的最初动机来自映射CMB，但这种多色地图制作方法将在整个天体物理学中具有更广泛的应用。
Broadband time-ordered data obtained from telescopes with a wavelength-dependent, asymmetric beam pattern can be used to extract maps at multiple wavelengths from a single scan. This technique is especially useful when collecting data on cosmic phenomena such as the Cosmic Microwave Background (CMB) radiation, as it provides the ability to separate the CMB signal from foreground contaminants. We develop a method to determine the optimal linear combinations of wavelengths (``colors'') that can be reconstructed for a given telescope design and the number of colors that are measurable with high signal-to-noise ratio. The optimal colors are found as eigenvectors of a matrix derived from the inverse noise covariance matrix. When the telescope is able to scan the sky isotropically, it is useful to transform to a spherical harmonic basis, in which this matrix has a particularly simple form. We propose using the optimal colors determined from the isotropic case even when the actual scanning pattern is not isotropic (e.g., covers only part of the sky). We perform simulations showing that maps in multiple colors can be reconstructed accurately from both full-sky and partial-sky scans. Although the original motivation for this research comes from mapping the CMB, this method of polychromatic map-making will have broader applications throughout astrophysics.
