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String-Inspired Triplet See-Saw from Diagonal Embedding of SU(2)_L in SU(2)_A x SU(2)_B

Paul Langacker·Brent D. Nelson
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Abstract

Motivated by string constructions, we consider a variant on the Type II see-saw mechanism involving the exchange of triplet representations of SU(2)_L in which this group arises from a diagonal embedding into SU(2)_A x SU(2)_B. A natural assignment of Standard Model lepton doublets to the two underlying gauge groups results in a bimaximal pattern of neutrino mixings and an inverted hierarchy in masses. Simple perturbations around this leading-order structure can accommodate the observed pattern of neutrino masses and mixings.

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Paul Langacker, Brent D. Nelson. 2005-07-05. String-Inspired Triplet See-Saw from Diagonal Embedding of SU(2)_L in SU(2)_A x SU(2)_B. https://doi.org/10.1103/physrevd.72.053013

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