mu-tau Symmetry and Charged Lepton Mass Hierarchy in a Supersymmetric D4 Model

Understand

In this note we discuss a supersymmetric (SUSY) D4 x Z5 model which leads to vanishing reactor mixing angle theta_13=0 and maximal atmospheric mixing theta_23=pi/4 in the lepton sector at leading order (LO), due to the preservation of non-trivial distinct D4 subgroups in the charged lepton and neutrino sectors, respectively.

• The solar mixing angle theta_12 remains undetermined and is expected to be of order one.
• Since right-handed charged leptons transform as singlets under D4, the charged lepton mass hierarchy can be naturally accounted for.
• The model predicts inverted mass hierarchy for neutrinos.