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arXiv · 1304.5493

Low Variance at large scales of WMAP 9 year data

A. Gruppuso·P. Natoli·F. Paci·F. Finelli·D. Molinari·A. De Rosa·N. Mandolesi
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Abstract

We use an optimal estimator to study the variance of the WMAP 9 CMB field at low resolution, in both temperature and polarization. Employing realistic Monte Carlo simulation, we find statistically significant deviations from the $\Lambda$CDM model in several sky cuts for the temperature field. For the considered masks in this analysis, which cover at least the 54% of the sky, the WMAP 9 CMB sky and $\Lambda$CDM are incompatible at $ \ge 99.94%$ C.L. at large angles ($>5^\circ$). We find instead no anomaly in polarization. As a byproduct of our analysis, we present new, optimal estimates of the WMAP 9 CMB angular power spectra from the WMAP 9 year data at low resolution.

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A. Gruppuso, P. Natoli, F. Paci, F. Finelli, D. Molinari, A. De Rosa, N. Mandolesi. 2013-04-19. Low Variance at large scales of WMAP 9 year data. https://doi.org/10.1088/1475-7516%2F2013%2F07%2F047

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