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arXiv · astro-ph/0302536

Lensing Reconstruction with CMB Temperature and Polarization

Michael Kesden·Asantha Cooray·Marc Kamionkowski
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Abstract

Weak gravitational lensing by intervening large-scale structure induces a distinct signature in the cosmic microwave background (CMB) that can be used to reconstruct the weak-lensing displacement map. Estimators for individual Fourier modes of this map can be combined to produce an estimator for the lensing-potenial power spectrum. The naive estimator for this quantity will be biased upwards by the uncertainty associated with reconstructing individual modes; we present an iterative scheme for removing this bias. The variance and covariance of the lensing-potenial power spectrum estimator are calculated and evaluated numerically in a $Λ$CDM universe for Planck and future polarization-sensitive CMB experiments.

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Michael Kesden, Asantha Cooray, Marc Kamionkowski. 2003-02-25. Lensing Reconstruction with CMB Temperature and Polarization. https://doi.org/10.1103/physrevd.67.123507

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