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arXiv 0807.1538astro-ph
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Sloan数字巡天星系角功率谱的信息量及其对弱透镜分析的意义

Information Content in the Galaxy Angular Power Spectrum from the Sloan Digital Sky Survey and Its Implication on Weak Lensing Analysis

Jounghun Lee, Ue-Li Pen

摘要:

利用Sloan数字巡天数据Release 5(SDSS DR 5)的光度红移星表,利用Rimes-Hamilton方法估算星系角功率谱中的Fisher信息。发现在红移0.1<= photo-z <0.5的范围内,星系角功率谱中包含的Fisher信息量在透镜多极标度300<= 1 <= 2000处达到饱和。在l=2000时,观测到的信息比高斯波动的情况低两个数量级。这在观测上支持了密度功率谱的translinear区域包含的关于初始宇宙学条件的独立信息很少,这与Rimes-Hamilton的数值趋势一致。我们的研究结果还表明,高斯噪声描述可能是无效的弱透镜测量。

英文摘要:

We analyze the photometric redshift catalog of the Sloan Digital Sky Survey Data Release 5 (SDSS DR5) to estimate the Fisher information in the galaxy angular power spectrum with the help of the Rimes-Hamilton technique. It is found that the amount of Fisher information contained in the galaxy angular power spectrum is saturated at lensing multipole scale 300<= l <= 2000 in the redshift range 0.1<= photo-z <0.5. At l=2000, the observed information is two orders of magnitude lower than the case of Gaussian fluctuations. This supports observationally that the translinear regime of the density power spectrum contains little independent information about the initial cosmological conditions, which is consistent with the numerical trend shown by Rimes-Hamilton. Our results also suggest that the Gaussian-noise description may not be valid in weak lensing measurements.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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