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Analysis of three-neutrino oscillations in the full mixing angle space

D. C. Latimer·D. J. Ernst
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Abstract

We use a model, with no CP violation, of the world's neutrino oscillation data, excluding the LSND experiments, and search the full parameter space ($0\leqθ_{12} \le π/2$; $-π/2 \le θ_{13} \le π/2$; and 0\leqθ_{23} \le π/2$) for the best fit values of the mixing angles and mass-squared differences. We find that the mixing angle $θ_{13}$ is bounded by $-0.15<θ_{13}<0.20$ with an absolute minimum at $θ_{13}=0.12$ and a local minimum at $-0.04$. The importance of the negative $θ_{13}$ region and this structure in the chi-square space has heretofore been overlooked because the factorization approximation commonly employed yields oscillation probabilities that are a function of $\sin^2θ_{13}$.

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D. C. Latimer, D. J. Ernst. 2004-12-23. Analysis of three-neutrino oscillations in the full mixing angle space. https://arxiv.org/abs/nucl-th/0404059

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