Unbiased estimation of an angular power spectrum
Unbiased estimation of an angular power spectrum
复制标题
角功率谱的无偏估计
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
N. Vittorio
中科院分区：
文献类型：
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作者：
G. Polenta;D. Marinucci;A. Balbi;P. Bernardis;E. Hivon;S. Masi;P. Natoli;N. Vittorio
我们讨论了从多探测器 CMB 各向异性图导出互功率谱估计器的分析特性。该方法计算方便，并且在非常广泛的假设下提供无偏估计。我们还提出了一种新的程序来测试由于伪 Cl 估计中不适当的噪声扣除而导致的残余偏差的存在。我们在原假设下推导了该过程的分析行为，并使用蒙特卡罗模拟来研究其效率特性，这看起来非常有前途。例如，对于具有各向同性白噪声的全天空图，测试能够识别噪声幅度估计的 1% 误差。
We discuss the derivation of the analytic properties of the cross-power spectrum estimator from multi-detector CMB anisotropy maps. The method is computationally convenient and it provides unbiased estimates under very broad assumptions. We also propose a new procedure for testing for the presence of residual bias due to inappropriate noise subtraction in pseudo-Cl estimates. We derive the analytic behaviour of this procedure under the null hypothesis, and use Monte Carlo simulations to investigate its efficiency properties, which appear very promising. For instance, for full sky maps with isotropic white noise, the test is able to identify an error of 1% on the noise amplitude estimate.