See-saw realization of the texture zeros in the neutrino mass matrix

We study the see-saw realization of seven textures of the neutrino mass matrix, which were presented by Frampton, Glashow and Marfatia. Two of them (B-1 and B-2) are not realized in the see-saw mechanism without fine-tuning of parameters. We present some specific textures of the Dirac neutrino mass matrix and the right-handed Majorana neutrino one. In order to test these textures, we discuss the effect on the branching ratio of mu --> egamma. We also study the U(1)(X) x U(1)(X'), flavor symmetry, in which U(1)(X) is anomalous and U(1)(X') is non-anomalous, to reproduce texture zeros. We present examples of U(1) charges for two textures (A(1) and A(2)). (C) 2002 Elsevier Science B.V. All rights reserved.