Constraints on mode couplings and modulation of the CMB with WMAP data

Simon Prunet; Jean-Philippe Uzan; Francis Bernardeau; Tristan Brunier

doi:10.1103/physrevd.71.083508

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arXiv · astro-ph/0406364

Constraints on mode couplings and modulation of the CMB with WMAP data

Simon Prunet·Jean-Philippe Uzan·Francis Bernardeau·Tristan Brunier

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Abstract

We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation. Such a modulation is found to induce correlations between multipoles with $Δ\ell=1$. Applying this estimator, to the V and W bands of the WMAP data, we found a significant detection in the V band. We argue however that foregrounds and in particular point sources are the origin of this signal.

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Simon Prunet, Jean-Philippe Uzan, Francis Bernardeau, Tristan Brunier. 2004-06-16. Constraints on mode couplings and modulation of the CMB with WMAP data. https://doi.org/10.1103/physrevd.71.083508

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