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arXiv · 1804.07586

Cosmic-ray fermion decay through tau-antitau emission with Lorentz violation

C. A. Escobar·J. P. Noordmans·R. Potting
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Abstract

We study CPT and Lorentz violation in the tau-lepton sector of the Standard Model in the context of the Standard-Model Extension, described by a coefficient which is thus far unbounded by experiment. We show that any non-zero value of this coefficient implies that, for sufficiently large energies, standard-model fermions become unstable against decay due to the emission of a pair of tau-antitau leptons. We calculate the induced fermion energy-loss rate and we deduce the first limit on the Lorentz- and CPT-violating coefficient.

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C. A. Escobar, J. P. Noordmans, R. Potting. 2018-04-20. Cosmic-ray fermion decay through tau-antitau emission with Lorentz violation. https://doi.org/10.1103/physrevd.97.115030

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