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arXiv · 1210.0308

Primordial Magnetism in CMB B-modes

Levon Pogosian·Tanmay Vachaspati·Amit Yadav
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Abstract

Cosmic Microwave Background (CMB) polarization B-modes induced by Faraday Rotation (FR) can provide a distinctive signature of primordial magnetic fields because of their characteristic frequency dependence and because they are only weakly damped on small scales. FR also leads to mode-coupling correlations between the E and B type polarization, and between the temperature and the B-mode. These additional correlations can further help distinguish magnetic fields from other sources of B-modes. We review the FR induced CMB signatures and present the constraints on primordial magnetism that can be expected from upcoming CMB experiments. Our results suggest that FR of CMB will be a promising probe of primordial magnetic fields.

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Levon Pogosian, Tanmay Vachaspati, Amit Yadav. 2012-10-01. Primordial Magnetism in CMB B-modes. https://doi.org/10.1139/cjp-2012-0401

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