Lensing reconstruction with CMB temperature and polarization

Weak gravitational lensing by an 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-potential 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-potential power spectrum estimator are calculated and evaluated numerically in a LCDM universe for Planck and future polarization-sensitive CMB experiments.