Global neutrino data and recent reactor fluxes: status of three-flavour oscillation parameters

TL;DR

This paper provides a comprehensive global analysis of three-flavour neutrino oscillation data, incorporating recent experimental results and updated reactor flux calculations, to assess the status of the mixing angle θ13 and neutrino mass hierarchy.

Contribution

It offers the first combined analysis including latest MINOS, solar, atmospheric, and reactor data with updated reactor fluxes, refining the understanding of neutrino oscillation parameters.

Findings

Weak hint for non-zero θ13 at 1.8σ

Results depend on reactor neutrino flux assumptions

Analysis impacts the interpretation of neutrino mass hierarchy

Abstract

We present the results of a global neutrino oscillation data analysis within the three-flavour framework. We include latest results from the MINOS long-baseline experiment (including electron neutrino appearance as well as anti-neutrino data), updating all relevant solar (SK II+III), atmospheric (SK I+II+III) and reactor (KamLAND) data. Furthermore, we include a recent re-calculation of the anti-neutrino fluxes emitted from nuclear reactors. These results have important consequences for the analysis of reactor experiments and in particular for the status of the mixing angle $\theta_{13}$. In our recommended default analysis we find from the global fit that the hint for non-zero $\theta_{13}$ remains weak, at 1.8$\sigma$ for both neutrino mass hierarchy schemes. However, we discuss in detail the dependence of these results on assumptions concerning the reactor neutrino analysis.