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arXiv · 1212.6658

CMB lensing reconstruction from the WMAP 7-year data

C. Sofia Carvalho·Ismael Tereno·Spyros Basilakos
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Abstract

We attempt to make a direct measurement of the weak lensing signal from the WMAP 7-year data. We apply the real-space implementation of the optimal quadratic estimator on the maps produced by the W-band Differencing Assemblies. We obtain a weak lensing amplitude parameter of $A_{L}=0.99\pm1.67$ after correcting for several sources of bias. The error budget includes a contribution from the bias removal procedure. Despite the demonstrated insensitivity of the real-space estimator to uncorrelated noise, we conclude that this detection is not statistically significant. We expect that a full-sky, higher-sensitivity experiment such as Planck will allow us to make a more significant measurement.

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C. Sofia Carvalho, Ismael Tereno, Spyros Basilakos. 2013-09-07. CMB lensing reconstruction from the WMAP 7-year data. https://doi.org/10.1103/physrevd.88.062002

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