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Status of neutrino oscillations II: How to reconcile the LSND result?

Thomas Schwetz
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Abstract

We present an analysis of the global neutrino oscillation data including the LSND result in terms of four-neutrino mass schemes and a CPT violating three-neutrino framework. We find that the strong preference of oscillations into active neutrinos implied by recent solar+KamLAND as well as atmospheric neutrino data allows to rule out (2+2) mass schemes at 5.8$σ$, whereas (3+1) schemes are disfavoured at the 3.2$σ$ level by short-baseline experiments. The CPT violating scenario is disfavoured at 3.4$σ$ by KamLAND and atmospheric anti-neutrino data. We conclude that currently no convincing explanation for the LSND signal exists, and it remains a puzzle how to reconcile it with the other evidences for neutrino oscillations.

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Thomas Schwetz. 2003-11-18. Status of neutrino oscillations II: How to reconcile the LSND result?. https://arxiv.org/abs/hep-ph/0311217

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