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arXiv · 1101.2019

Vacuum Cherenkov Radiation In Quantum Electrodynamics With High-Energy Lorentz Violation

Damiano Anselmi·Martina Taiuti
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Abstract

We study phenomena predicted by a renormalizable, CPT invariant extension of the Standard Model that contains higher-dimensional operators and violates Lorentz symmetry explicitly at energies greater than some scale Lambda_{L}. In particular, we consider the Cherenkov radiation in vacuo. In a rather general class of dispersion relations, there exists an energy threshold above which radiation is emitted. The threshold is enhanced in composite particles by a sort of kinematic screening mechanism. We study the energy loss and compare the predictions of our model with known experimental bounds on Lorentz violating parameters and observations of ultrahigh-energy cosmic rays. We argue that the scale of Lorentz violation Lambda_{L} (with preserved CPT invariance) can be smaller than the Planck scale, actually as small as 10^{14}-10^{15} GeV. Our model also predicts the Cherenkov radiation of neutral particles.

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Damiano Anselmi, Martina Taiuti. 2011-01-11. Vacuum Cherenkov Radiation In Quantum Electrodynamics With High-Energy Lorentz Violation. https://doi.org/10.1103/physrevd.83.056010

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