Radiative corrections and explicit perturbations to the tetra-maximal neutrino mixing with large theta_13

Understand

The tetra-maximal neutrino mixing pattern predicts a relatively large reactor mixing angle theta_13 \approx 8.4^\circ, which is in good agreement with the latest best-fit value theta_13 = 9^\circ.

• However, its prediction for theta_12 \approx 30.4^\circ is inconsistent with current oscillation data at the 3sigma C.L.
• We show that explicit perturbations to the tetra-maximal mixing can naturally enhance theta_12 to its best-fit value theta_12 = 34^\circ.
• Furthermore, we demonstrate that if the tetra-maximal mixing is produced by a certain flavor symmetry at a high-energy scale Lambda = 10^14 GeV, significant radiative corrections in the minimal supersymmetric standard model can modify theta_12 to be compatible with experimental data at the electroweak scale Lambda_EW = 10^2 GeV.