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arXiv · 0911.2965

Neutrino oscillations: Inevitability of non-standard interactions or a sterile neutrino

Abstract

We conjecture that the neutrino mixing matrix must be such that in the flavour oscillation process the energy expectation values enjoy flavour independence. Based on this conjecture we present unitarity and energy conservation constraints on neutrino oscillation parameters. In our analysis θ_{13} depends on the ratio of the mass-squared differences ζand on θ_{12} alone; while δ_{CP} is completely determined by ζ, θ_{12}, and θ_{23}. The standard neutrino oscillation phenomenology (SNOP) suggests ζ\approx 30. The resulting prediction for θ_{13} conflicts with SNOP expectation for all values of θ_{12}. This leads to the suggestion that some non-standard neutrino interactions may be intervening to invalidate the SNOP inferred ζand θ_{13}. An alternate inference is to go beyond the three flavours of SNOP and incorporate sterile neutrinos in the analysis.

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D. V. Ahluwalia, D. Schritt. 2009-11-16. Neutrino oscillations: Inevitability of non-standard interactions or a sterile neutrino. https://arxiv.org/abs/0911.2965

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