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Constraints on the photon charge based on observations of extragalactic sources

V. V. Kobychev·S. B. Popov
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Abstract

Using modern high-resolution observations of extragalactic compact radio sources we obtain an estimate of the upper bound on a photon electric charge at the level $e_γ \lesssim 3 \cdot 10^{-33}$ of elementary charge (assuming the photon charge to be energy independent). This is three orders of magnitude better than the limit obtained with radio pulsar timing. Also we set a limit on a photon charge in the gamma-ray band (energies about 0.1 MeV). In future the estimate made for extragalactic sources can be significantly improved.

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V. V. Kobychev, S. B. Popov. 2004-11-30. Constraints on the photon charge based on observations of extragalactic sources. https://doi.org/10.1134/1.1883345

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