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arXiv · 1006.1979

New constraints on Parity Symmetry from a re-analysis of the WMAP-7 low resolution power spectra

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

The Parity symmetry of the Cosmic Microwave Background (CMB) pattern as seen by WMAP 7 is tested jointly in temperature and polarization at large angular scale. A Quadratic Maximum Likelihood (QML) estimator is applied to the WMAP 7 year low resolution maps to compute all polarized CMB angular power spectra. The analysis is supported by 10000 realistic Monte-Carlo realizations. We confirm the previously reported Parity anomaly for TT in the range $\delta \ell=[2,22]$ at $> 99.5%$ C.L.. No anomalies have been detected in TT for a wider $\ell$ range (up to $\ell_{max}=40$). No violations have been found for EE, TE and BB which we test here for the first time. The cross-spectra TB and EB are found to be consistent with zero. We also forecast {\sc Planck} capabilities in probing Parity violations on low resolution maps.

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A. Gruppuso, F. Finelli, P. Natoli, F. Paci, P. Cabella, A. De Rosa, N. Mandolesi. 2010-06-10. New constraints on Parity Symmetry from a re-analysis of the WMAP-7 low resolution power spectra. https://doi.org/10.1111/j.1365-2966.2010.17773.x

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