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arXiv · 2208.01164

CP-violation search with T2K data

J. G. Walsh
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Abstract

The T2K experiment is a long-baseline neutrino oscillation experiment which uses $ν_μ$ and $\barν_μ$ beams to constrain CP-violating effects in a 3-flavor PMNS neutrino mixing model. Through $ν_μ\toν_{e}$ and $\barν_μ\to\barν_{e}$ appearance channels, T2K is sensitive to CP-violating effects in neutrino mixing. An excess of $ν_{e}$ candidates in the $ν$-beam mode is observed when compared to the CP conserving cases. T2K finds a best fit value of $δ_{\mathrm{CP}}=-1.97_{-0.70}^{+0.97}$ using Feldman-Cousins corrected intervals and excludes CP-conserving values of $δ_{\mathrm{CP}}$ of $0$ and $π$ at the 90% CL. $J_{\mathrm{CP}}=0$ is also excluded at 2$σ$ when using a flat prior in $δ_{\mathrm{CP}}$, favoring negative values.

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J. G. Walsh. 2022-08-01. CP-violation search with T2K data. https://arxiv.org/abs/2208.01164

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