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arXiv · 1205.4969

Photon-photon interactions as a source of CMB circular polarization

R. F. Sawyer
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Abstract

Photon-photon interactions mediated by the neutral hydrogen background can transform plane polarization into circular polarization, through completely forward processes, [gamma+gamma+atom-> gamma+ gamma+atom], in which only the photon polarizations are changed. The ratio of circular to plane polarization intensities is predicted to be at the level of several times 10^{-5} for some regions of angular size less than 1/300 and with large plane polarizations.

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R. F. Sawyer. 2012-05-22. Photon-photon interactions as a source of CMB circular polarization. https://arxiv.org/abs/1205.4969

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