学术文献库

We present results of a combined analysis in neutrino oscillations without unitarity assumption in the $3ν$ mixing picture. Constraints on neutrino mixing matrix elements are based on recent data from the reactor, solar and long-baseline accelerator neutrino oscillation experiments. The current data are consistent with the standard $3ν$ scheme. The precision on different matrix elements can be as good as a few percent at $3σ$ CL, and is mainly limited by the experimental statistical uncertainty. The $ν_e$ related elements are the most precisely measured among all sectors with the uncertainties $<20\%$. The measured leptonic CP violation is very close to the one assuming the standard $3ν$ mixing. The deviations on normalization and the unitarity triangle closure are confined within $\mathcal{O}(10^{-3})$, $\mathcal{O}(10^{-2})$ and $\mathcal{O}(10^{-1})$, for $ν_e$, $ν_μ$ and $ν_τ$ sectors, respectively. We look forward to the next-generation neutrino oscillation experiments \textit{such as} DUNE, T2HK, and JUNO, especially the precise measurements on $ν_τ$ oscillations, to significantly improve the precision of unitarity test on the $3ν$ mixing matrix.