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arXiv · 0902.4413

B-mode CMB Polarization from Patchy Screening during Reionization

Cora Dvorkin·Wayne Hu·Kendrick M. Smith
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Abstract

B-modes in CMB polarization from patchy reionization arise from two effects: generation of polarization from scattering of quadrupole moments by reionization bubbles, and fluctuations in the screening of E-modes from recombination. The scattering contribution has been studied previously, but the screening contribution has not yet been calculated. We show that on scales smaller than the acoustic scale (l>300), the B-mode power from screening is larger than the B-mode power from scattering. The ratio approaches a constant ~2.5 below the damping scale (l>2000). On degree scales relevant for gravitational waves (l<100), screening B-modes have a white noise tail and are subdominant to the scattering effect. These results are robust to uncertainties in the modeling of patchy reionization.

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Cora Dvorkin, Wayne Hu, Kendrick M. Smith. 2009-05-18. B-mode CMB Polarization from Patchy Screening during Reionization. https://doi.org/10.1103/physrevd.79.107302

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