CMB lensing and primordial non-Gaussianity
Abstract
We study the effects of gravitational lensing on the estimation of non-Gaussianity from the bispectrum of the cosmic microwave background (CMB) temperature anisotropies. We find that the effect of lensing on the bispectrum may qualitatively be described as a smoothing of the acoustic features analogous to the temperature power spectrum. In contrast to previous results, for a Planck-like experiment which is cosmic-variance limited to L=2000, we find that lensing causes no significant degradation of our ability to constrain the non-Gaussianity amplitude fNL for both local and equilateral configurations, provided that the biases due to the cross correlation between the lensing potential and the integrated-Sachs-Wolfe (ISW) contribution to the CMB temperature are adequately understood. With numerical simulations, we also verify that low-order Taylor approximations to the lensed bispectrum and ISW-lensing biases are accurate.
Keywords
Cite
@article{arxiv.0905.4732,
title = {CMB lensing and primordial non-Gaussianity},
author = {Duncan Hanson and Kendrick M. Smith and Anthony Challinor and Michele Liguori},
journal= {arXiv preprint arXiv:0905.4732},
year = {2010}
}
Comments
pdflatex to fix incorrectly rendered plots