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arXiv · 1111.2371

Reconstruction of Gravitational Lensing Using WMAP 7-Year Data

Chang Feng·Brian Keating·Hans P. Paar·Oliver Zahn
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Abstract

Gravitational lensing by large scale structure introduces non-Gaussianity into the Cosmic Microwave Background and imprints a new observable, which can be used as a cosmological probe. We apply a four-point estimator to the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year coadded temperature maps alone to reconstruct the gravitational lensing signal. The Gaussian bias is simulated and subtracted, and the higher order bias is investigated. We measure a gravitational lensing signal with a statistical amplitude of $\mathcal {C}$ = $1.27\pm 0.98$ using all the correlations of the W- and V-band Differencing Assemblies (DAs). We therefore conclude that WMAP 7-year data alone, can not detect lensing.

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Chang Feng, Brian Keating, Hans P. Paar, Oliver Zahn. 2011-11-09. Reconstruction of Gravitational Lensing Using WMAP 7-Year Data. https://doi.org/10.1103/physrevd.85.043513

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