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arXiv · hep-ph/9409461

Pulsar Bound on the Photon Electric Charge Reexamined

Georg G. Raffelt
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Abstract

If photons had a small electric charge $Q_γ$ their path in the galactic magnetic field would be curved, leading to a time delay between photons of different frequency from a distant source. Cocconi's previous application of this argument led to a limit which is too restrictive by a factor of about 200; the corrected bound is $Q_γ/e\lapprox10^{-29}$.

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Georg G. Raffelt. 1994-09-30. Pulsar Bound on the Photon Electric Charge Reexamined. https://doi.org/10.1103/physrevd.50.7729

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