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Fermion masses and proton decay in string-inspired SU(4)*SU(2)^2*U(1)_X

Thomas Dent·George Leontaris·John Rizos
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Abstract

We present a supersymmetric model of fermion masses with SU(4)*SU(2)^2*U(1)_X gauge group with matter in fundamental and antisymmetric tensor representations only. The up, down, charged lepton and neutrino Yukawa matrices are distinguished by different Clebsch-Gordan coefficients due to contracting over SU(4) and SU(2)_R indices. We obtain a hierarchical light neutrino mass spectrum with bi-large mixing. The condition that anomalies be cancelled by a Green-Schwarz mechanism leads to fractional U(1)_X charges which exclude $B$ violation through dimension-4 and -5 operators.

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Thomas Dent, George Leontaris, John Rizos. 2004-07-13. Fermion masses and proton decay in string-inspired SU(4)*SU(2)^2*U(1)_X. https://doi.org/10.1016/j.physletb.2004.11.032

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