We propose an A_4 flavor-symmetric SU(3)xSU(2)xU(1) seesaw model where lepton number is broken spontaneously. A consistent two-zero texture pattern of neutrino masses and mixing emerges from the interplay of type-I and type-II seesaw contributions, with important phenomenological predictions. We show that, if the Majoron becomes massive, such seesaw scenario provides a viable candidate for decaying dark matter, consistent with cosmic microwave background lifetime constraints that follow from current WMAP observations. We also calculate the sub-leading one-loop-induced decay into photons which leads to a mono-energetic emission line that may be observed in future X-ray missions such as Xenia.
Esteves, J. N. Joaquim, F.R. Joshipura, Anjan S. Romao, J. C. Tórtola Baixauli, María Amparo Furtado Valle, José Wagner 2010 A(4)-based neutrino masses with Majoron decaying dark matter Physical Review D 82 7 073008











