Spontaneous breaking of a global symmetry in a 3-3-1 model - art. no. 115003

In a 3-3-1 model in which the lepton masses arise from a scaler sextet it i s possible to break spontaneously a global symmetry which implies in a pseu doscalar Majoron-like Goldstone boson. This Majoron does not mix with any o ther scalar fields and for this reason it does not couple, at the tree leve l, to either the charged leptons or to the quarks. Moreover, its interactio n with neutrinos is diagonal. We also argue that there is a sec: of paramet ers in which the model can be consistent with the invisible Z(0) width and that heavy neutrinos can decay sufficiently rapid by Majoron emission, havi ng a lifetime shorter than the age of the universe. [S0556-2821(99)02217-1] .