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MACRO constraints on violation of Lorentz invariance

M. Cozzi
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Abstract

The energy spectrum of neutrino-induced upward-going muons in MACRO has been analysed in terms of relativity principles violating effects, keeping standard mass-induced atmospheric neutrino oscillations as the dominant source of $ν_μ \to ν_τ$ transitions. The data disfavor these exotic possibilities even at a sub-dominant level, and stringent 90% C.L. limits are placed on the Lorentz invariance violation parameter $|Δv| < 6 \times 10^{-24}$ at $\sin 2θ_v$ = 0 and $|Δv| < 2.5 ÷5 \times 10^{-26}$ at $\sin 2θ_v$ = $\pm$1. These limits can also be re-interpreted as upper bounds on the parameters describing violation of the Equivalence Principle.

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M. Cozzi. 2007-03-08. MACRO constraints on violation of Lorentz invariance. https://doi.org/10.1016/j.nuclphysbps.2007.02.089

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