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Comments on atmospheric neutrino oscillation scenarios with large nu_mu <-> nu_e transitions

G. L. Fogli·E. Lisi·A. Marrone·G. Scioscia
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Abstract

The evidence for $ν_μ$ disappearance in the Super-Kamiokande atmospheric neutrino experiment and the negative searches for $ν_e$ disappearance in the CHOOZ reactor experiment can be easily reconciled by assuming oscillations with large amplitude in the $ν_μ\leftrightarrowν_τ$ channel and small (or null) amplitude in the $ν_μ\leftrightarrowν_e$ channel. It has been claimed, however, that some oscillation scenarios with large $ν_μ\leftrightarrowν_e$ mixing can also be constructed in agreement with the present data. We investigate quantitatively two such scenarios: (a) threefold maximal mixing; and (b) attempts to fit all sources of evidence for oscillations (solar, atmospheric, and accelerator) with three neutrinos. By using mainly Super-Kamiokande data, we show that the case (a) is disfavored, and that the case (b) is definitely ruled out.

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G. L. Fogli, E. Lisi, A. Marrone, G. Scioscia. 1999-06-22. Comments on atmospheric neutrino oscillation scenarios with large nu_mu <-> nu_e transitions. https://arxiv.org/abs/hep-ph/9906450

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