Neutrino Masses and Family Symmetry
نویسنده
چکیده
Neutrino masses in the 100 eV-1 MeV range are permitted if there is a spontaneously broken global family symmetry that allows the heavy neutrinos to decay by Goldstone boson emission with a cosmologically acceptable lifetime. The family symmetry may be either abelian or nonabelian; we present models illustrating both possibilities. If the family symmetry is nonabelian, then the decay ~" ---, # + Goidstone boson or ~" ~ e + Goldstone boson may have an observable rate.
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