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arXiv · 1503.08879

On the description of non-unitary neutrino mixing

F. J. Escrihuela·D. V. Forero·O. G. Miranda·M. Tortola·J. W. F. Valle
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Abstract

Neutrino oscillations are well established and the relevant parameters determined with good precision, except for the CP phase, in terms of a unitary lepton mixing matrix. Seesaw extensions of the Standard Model predict unitarity deviations due to the admixture of heavy isosinglet neutrinos. We provide a complete description of the unitarity and universality deviations in the light neutrino sector. Neutrino oscillation experiments involving electron or muon neutrinos and anti-neutrinos are fully described in terms of just three new real parameters and a new CP phase, in addition to the ones describing oscillations with unitary mixing. Using this formalism we describe the implications of non-unitarity for neutrino oscillations and summarize the model-independent constraints on heavy neutrino couplings that arise from current experiments.

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F. J. Escrihuela, D. V. Forero, O. G. Miranda, M. Tortola, J. W. F. Valle. 2015-03-31. On the description of non-unitary neutrino mixing. https://doi.org/10.1103/physrevd.92.053009

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