Document Type

Article

Date

5-6-2006

Language

English

Disciplines

Physics

Description/Abstract

The form of the leptonic mixing matrix emerging from experiment has, in the last few years, generated a lot of interest in the so-called tribimaximal type. This form may be naturally associated with the possibility of a discrete permutation symmetry (S_3) among the three generations. However, trying to implement this attractive symmetry has resulted in some problems and it seems to have fallen out of favor. We suggest an approach in which the S_3 holds to first approximation, somewhat in the manner of the old SU(3) flavor symmetry of the three flavor quark model. It is shown that in the case of the neutrino sector, a presently large experimentally allowed region can be fairly well described in this first approximation. We briefly discuss the nature of the perturbations which are the analogs of the Gell-Mann Okubo perturbations but confine our attention for the most part to the S_3 invariant model. We postulate that the S_3 invariant mass spectrum consists of non zero masses for the (\tau,b,t) and zero masses for the other charged fermions but approximately degenerate masses for the three neutrinos. The mixing matrices are assumed to be trivial for the charged fermions but of tribimaximal type for the neutrinos in the first approximation. It is shown that this can be implemented by allowing complex entries for the mass matrix and spontaneous breakdown of the S_3 invariance of the Lagrangian.

Additional Information

24 pages, 1 figure, minor corrections and acknowledgment added. To appear in IJMP More information available at http://arxiv.org/abs/hep-ph/0605069

Source

Harvested from Arxiv.org

Creative Commons License


This work is licensed under a Creative Commons Attribution 3.0 License.

Included in

Physics Commons

Share

COinS