GEOMETRICAL NEUTRINO MASS HIERARCHY AND A 17-KEV V-TAU

We present an extension of the singlet majoron gauge model which realizes a novel scheme of geometrical neutrino mass hierarchy proposed recently by Glashow, wherein nu-e and nu-mu are Majorana particles with m-nu-e almost-equal-to m-nu-mu almost-equal-to 10(-3) eV while nu-tau is a Dirac particle with a mass of 17 keV. Our model explains the solar-neutrino deficit via the Mikheyev-Smirnov-Wolfenstein mechanism and accounts for the recently reported anomaly in beta-decay spectra in a natural manner without any undesirable fine tuning of parameters. An interesting consequence of the model is that nu-tau is short lived with a lifetime of almost-equal-to 10(-3)-10(-1) sec.