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arXiv · 1107.2013

Can axion-like particles explain the alignments of the polarisations of light from quasars?

A. Payez·J. R. Cudell·D. Hutsemékers
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Abstract

The standard axion-like particle explanation of the observed large-scale coherent orientations of quasar polarisation vectors is ruled out by the recent measurements of vanishing of circular polarisation. We introduce a more general wave-packet formalism and show that, although decoherence effects between waves of different frequencies can reduce significantly the amount of circular polarisation, the axion-like particle hypothesis is disfavoured given the bandwidth with which part of the observations were performed. Finally, we show that a more sophisticated model of extragalactic fields does not lead to an alignment of polarisations.

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A. Payez, J. R. Cudell, D. Hutsemékers. 2011-07-11. Can axion-like particles explain the alignments of the polarisations of light from quasars?. https://doi.org/10.1103/physrevd.84.085029

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