Off-diagonal structure of neutrino mass matrix in see-saw mechanism and electron-muon-tau lepton universality

Abstract

By a simple extension of the standard model in which ($e-\mu -\tau$) universality is not conserved, we present a scenario within the framework of see-saw mechanism in which the neutrino mass matrix is strictly off-diagonal in the flavor basis. We show that a version of this scenario can accomodate the atmospheric $\nu_\mu -\nu_\tau$ neutrino oscillations and $\nu_\mu -\nu_e$ oscillations claimed by the LSND collaboration. PACS: 14.60.Pq; 14.60.St;13.15.+gComment: 5 pages, Revtex, 1 figure: The model accomodate another version which explains atmospheric neutrino data and the observed solar neutrino oscillations (large angle solution). In the previous version the value of \lambda parameter is changed to the expected one. This version now accomodates LSND result and solar neutrino oscillations (small angle MSW solution