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arXiv 0709.1144astro-ph
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方向相关原始功率谱的宇宙微波背景统计

Cosmic Microwave Background Statistics for a Direction-Dependent Primordial Power Spectrum

Anthony R. Pullen, Marc Kamionkowski

摘要:

原始微扰的统计各向同性是宇宙学中的一个常见假设,但这是一个需要检验的假设。为此,我们开发的原始功率谱,取决于方向,以及幅度,傅立叶波矢量的宇宙微波背景统计。我们首先考虑一个简单的估计,搜索在一个独立于模型的方式在平方的温度(和/或偏振)波动的各向异性。然后,我们构建的原始功率谱的方向依赖的球谐展开的系数的最小方差估计。为了说明这一点,我们将这些统计数据应用到一个暴胀模型中,该模型具有原始功率谱对方向的四极依赖性,并发现普朗克卫星可以检测到小至2.0%的功率四极。

英文摘要:

Statistical isotropy of primordial perturbations is a common assumption in cosmology, but it is an assumption that should be tested. To this end, we develop cosmic microwave background statistics for a primordial power spectrum that depends on the direction, as well as the magnitude, of the Fourier wavevector. We first consider a simple estimator that searches in a model-independent way for anisotropy in the square of the temperature (and/or polarization) fluctuation. We then construct the minimum-variance estimators for the coefficients of a spherical-harmonic expansion of the direction-dependence of the primordial power spectrum. To illustrate, we apply these statistics to an inflation model with a quadrupole dependence of the primordial power spectrum on direction and find that a power quadrupole as small as 2.0% can be detected with the Planck satellite.

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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