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arXiv · astro-ph/0205306

A Lensing Reconstruction of Primordial Cosmic Microwave Background Polarization

Asantha Cooray
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Abstract

We discuss a possibility to directly reconstruct the CMB polarization field at the last scattering surface by accounting for modifications imposed by the gravitational lensing effect. The suggested method requires a tracer field of the large scale structure lensing potentials that deflected propagating CMB photons from the last scattering surface. This required information can come from a variety of observations on the large scale structure matter distribution, including convergence reconstructed from lensing shear studies involving galaxy shapes. In the case of so-called curl, or B,-modes of CMB polarization, the reconstruction allows one to identify the distinct signature of inflationary gravitational waves.

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Asantha Cooray. 2002-05-17. A Lensing Reconstruction of Primordial Cosmic Microwave Background Polarization. https://doi.org/10.1103/physrevd.66.103509

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