PATTERN OF THE APPROXIMATE MASS DEGENERACY OF MAJORANA NEUTRINOS

Abstract

In view of the recently reported evidence for a nonzero Majorana mass of the electron neutrino, together with the established phenomena of atmospheric and solar neutrino oscillations, the case of three nearly mass-degenerate Majorana neutrinos is now an interesting possibility. We show in this paper how a natural pattern of symmetry breaking in the recently proposed A 4 model of Majorana neutrino masses can accommodate the data on neutrino oscillations, resulting in the predictions sin 2 2θ atm = 1 and sin 2 2θ sol = 2/3.