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Pathways to Naturally Small Neutrino Masses

Ernest Ma
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Abstract

In the minimal standard electroweak gauge model, there is an effective dimension-five operator which generates neutrino masses, and it has only three tree-level realizations. One is the canonical seesaw mechanism with a right-handed neutrino. Another is having a heavy Higgs triplet as recently proposed. The third is to have a heavy Majorana fermion triplet, an example of which is presented here in the context of supersymmetric SU(5) grand unification. The three generic one-loop realizations of this operator are also discussed.

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Ernest Ma. 1998-05-23. Pathways to Naturally Small Neutrino Masses. https://doi.org/10.1103/physrevlett.81.1171

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