Bandpass mismatch error for satellite CMB experiments II: correcting for the spurious signal
Bandpass mismatch error for satellite CMB experiments II: correcting for the spurious signal
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DOI：
10.1088/1475-7516/2019/07/043
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发表时间：
2019-02
影响因子：
6.4
通讯作者：
R. Banerji;G. Patanchon;J. Delabrouille;M. Hazumi;D. Hoang;H. Ishino;T. Matsumura
中科院分区：
文献类型：
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作者：
R. Banerji;G. Patanchon;J. Delabrouille;M. Hazumi;D. Hoang;H. Ishino;T. Matsumura
未来的宇宙微波背景（CMB）卫星任务旨在使用B模式偏振信号测量张量标量比r，灵敏度σ（r）为1000 -2量级。仪器特性（如光谱滤波器）表征中的小不确定性可能导致强度信号泄漏到偏振，并可能使原始信号的任何测量产生偏差。在本文中，我们讨论的方法，以避免和纠正的强度偏振泄漏，由于带通不匹配的探测器之间的设置。我们开发了一个模板拟合映射器，以获得泄漏信号的无偏估计，并将其从总信号中减去。使用模拟，我们展示了如何这样的方法可以减少所观察到的B模式信号的偏置功率高达3个数量级。
Future Cosmic Microwave Background (CMB) satellite missions aim at using the B-mode polarisation signal to measure the tensor-to-scalar ratio r with a sensitivity σ(r) of the order of ⩽ 10-2. Small uncertainties in the characterisation of instrument properties such as the spectral filters can lead to a leakage of the intensity signal to polarisation and can possibly bias any measurement of a primordial signal. In this paper we discuss methods for avoiding and correcting for the intensity to polarisation leakage due to bandpass mismatch among detector sets. We develop a template fitting map-maker to obtain an unbiased estimate of the leakage signal and subtract it out of the total signal. Using simulations we show how such a method can reduce the bias on the observed B-mode signal by up to 3 orders of magnitude in power.