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

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 ($0\le {\theta }_{12}\le \pi /2$; $-\pi /2\le {\theta }_{13}\le \pi /2$; and 0\leq\theta_{23} \le \pi /2$)forthebestfitvaluesofthemixinganglesandmass-squareddifferences.Wefindthatthemixingangle$\theta_{13}$isboundedby$-0.15<\theta_{13}<0.20$withanabsoluteminimumat$\theta_{13}=0.12$andalocalminimumat$-0.04$.Theimportanceofthenegative$\theta_{13}$regionandthisstructureinthechi-squarespacehasheretoforebeenoverlookedbecausethefactorizationapproximationcommonlyemployedyieldsoscillationprobabilitiesthatareafunctionof$\sin^2\theta_{13}$.

Comments: 4 pages, 3 figures