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arXiv · 0812.2207

Cosmic polarimetry in magnetoactive plasmas

Massimo Giovannini·Kerstin E. Kunze
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Abstract

Polarimetry of the Cosmic Microwave Background (CMB) represents one of the possible diagnostics aimed at testing large-scale magnetism at the epoch of the photon decoupling. The propagation of electromagnetic disturbances in a magnetized plasma leads naturally to a B-mode polarization whose angular power spectrum is hereby computed both analytically and numerically. Combined analyses of all the publicly available data on the B-mode polarization are presented, for the first time, in the light of the magnetized $Λ$CDM scenario. Novel constraints on pre-equality magnetism are also derived in view of the current and expected sensitivities to the B-mode polarization.

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Massimo Giovannini, Kerstin E. Kunze. 2008-12-11. Cosmic polarimetry in magnetoactive plasmas. https://doi.org/10.1103/physrevd.79.063007

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