CMB lensing reconstruction from the WMAP 7-year data

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 $A_L=0.99\pm 1.67$ 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.

19 pages, 8 figures, 3 tables. Revised version to be published in PRD

References in corpus (5)

• Detection of Gravitational Lensing in the Cosmic Microwave Background
• Correlation of CMB with large-scale structure: II. Weak lensing
• Bias-Hardened CMB Lensing
• CMB temperature lensing power reconstruction
• A Constraint On the Integrated Mass Power Spectrum out to z = 1100 from Lensing of the Cosmic Microwave Background