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arXiv · 1311.4114

New Results from the T2K Experiment: Observation of $ν_e$ Appearance in a $ν_μ$ Beam

Michael Wilking
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Abstract

The T2K Experiment has observed the appearance of electron neutrinos in a muon-neutrino beam. Twenty eight neutrino candidates pass the selection cuts with a predicted background of $4.64 \pm 0.53$ events, which corresponds to a 6.8$σ$ exclusion of $θ_{13} = 0$. When comparing the $θ_{13} = 0$ hypothesis to the best fit of the full electron momentum and angle distribution, $θ_{13} = 0$ is excluded at 7.5$σ$ for $\sin^2 2θ_{23} = 1$ and $δ_{CP} = 0$. In addition, results from the T2K $ν_μ$ disappearance analysis have also been updated to improve the treatment of full 3-flavor oscillations.

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Michael Wilking. 2013-12-02. New Results from the T2K Experiment: Observation of $ν_e$ Appearance in a $ν_μ$ Beam. https://arxiv.org/abs/1311.4114

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