A model of massive neutrinos with a conserved lepton number

Abstract We consider a left-right symmetric model with three generations and with the standard assignments of fermion and scalar fields. The left-right symmetrygives rise to a unique conserved lepton numberwhich is of the Zel'dovich-Konopinski-Mahmoud type. The neutrino mass matrixyields one Dirac and one Majorana neutrino, both in the light and in the heavy sector. Up to small mixings with right-handed neutrinos, the left-handed ν e and ν τ combine to the light Dirac neutrinowhereas ν μ is the light Majoranan neutrino. With a right-handed scale in the TeV range all light neutrino leptonmasses. Phenomenological consequences of the model are discussed. charged leptonmasses. Phenomenological consequences of the model are discussed.