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Cosmic Microwave Background Polarization Signals from Tangled Magnetic Fields

T. R. Seshadri·Kandaswamy Subramanian
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Abstract

Tangled, primordial cosmic magnetic fields create small rotational velocity perturbations on the last scattering surface (LSS) of the cosmic microwave background radiation (CMBR). For fields which redshift to a present value of $B_0 = 3\times 10^{-9}$ Gauss, these vector modes are shown to generate polarization anisotropies of order $0.1μK - 4 μK$ on small angular scales ($ 500 < l < 2000$), assuming delta function or a power law spectra with $n=-1$. About 200 times larger signals result for $n=2$ spectra. Unlike inflation generated, scalar modes, these signals are dominated by the odd parity, B-type polarization, which could help in their detection.

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T. R. Seshadri, Kandaswamy Subramanian. 2001-08-24. Cosmic Microwave Background Polarization Signals from Tangled Magnetic Fields. https://doi.org/10.1103/physrevlett.87.101301

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