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arXiv · 1510.05923

Searching for non-Gaussianity in the Planck data

M. J. Reboucas·A. Bernui
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Abstract

The statistical properties of the temperature anisotropies and polarization of the of cosmic microwave background (CMB) radiation offer a powerful probe of the physics of the early universe. In recent works a statistical procedure based upon the calculation of the kurtosis and skewness of the data in patches of CMB sky-sphere has been proposed and used to investigate the large-angle deviation from Gaussianity in WMAP maps. Here we briefly address the question as to how this analysis of Gaussianity is modified if the foreground-cleaned Planck maps are considered. We show that although the foreground-cleaned Planck maps present significant deviation from Gaussianity of different degrees when a less severe mask is used, they become consistent with Gaussianity, as detected by our indicators, when masked with the union mask U73.

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M. J. Reboucas, A. Bernui. 2015-10-20. Searching for non-Gaussianity in the Planck data. https://doi.org/10.1017/s1743921314013829

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