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arXiv · 0806.4351

Addendum: Ultrahigh-energy cosmic-ray bounds on nonbirefringent modified-Maxwell theory

F. R. Klinkhamer·M. Risse
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Abstract

Nonbirefringent modified-Maxwell theory, coupled to standard Dirac particles, involves nine dimensionless parameters, which can be bounded by the inferred absence of vacuum Cherenkov radiation for ultrahigh-energy cosmic rays (UHECRs). With selected UHECR events, two-sided bounds on the eight nonisotropic parameters are obtained at the 10^{-18} level, together with an improved one-sided bound on the single isotropic parameter at the 10^{-19} level.

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F. R. Klinkhamer, M. Risse. 2008-06-26. Addendum: Ultrahigh-energy cosmic-ray bounds on nonbirefringent modified-Maxwell theory. https://doi.org/10.1103/physrevd.77.117901

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