Neutrino texture-zeros after JUNO's first results: Implications for long-baseline neutrino experiments

Abstract

The recent results from the JUNO reactor neutrino experiment have significantly improved our knowledge of the solar mixing angle $\theta_{12}$ and the solar mass splitting $\Delta m^2_{21}$. We study the impact of these improved estimates on the validity of texture-zeros in the light neutrino mass matrix by assuming neutrinos to be of Majorana nature. Considering a diagonal charged lepton basis, we revisit the previously allowed one-zero and two-zero textures and check their validity by using updated neutrino data from JUNO. While JUNO data rule out one previously allowed two-zero texture, they also make predictions for other neutrino parameters more precise. We finally study the prospects of probing the currently allowed texture-zeros and their predicted correlations among neutrino parameters at the Deep Underground Neutrino Experiment (DUNE). The inclusion of JUNO and reactor experiments strengthens DUNE's ability to constrain the allowed parameter space of both one-zero and two-zero textures. We also observe that DUNE benefits substantially from the complementarity with the T2HK experiment.