Parallel Lepton Mass Matrices with Texture and Cofactor Zeros
  In this paper we investigate the parallel texture structures containing texture zeros in charged lepton mass matrix $M_{l}$ and cofactor zeros in neutrino mass matrix $M_{\nu}$. These textures are interesting since they are related to the $Z_{n}$ flavor symmetries. Using the weak basis permutation transformation, the 15 parallel textures are grouped as 4 classes (class I,II,III and IV) with the matrices in each class sharing the same physical implications. Under the current experimental data, the class I, III with inverted mass hierarchy and class II with normal mass hierarchy are phenomenologically acceptable. The correlations between some important physical variables are presented, which are essential for the model selection and can be text by future experiments. The model realization is illustrated by means of $Z_{4}\times Z_{2}$ flavor symmetry. 
Weijian Wang
hep-ph