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Softly Broken A_4 Symmetry for Nearly Degenerate Neutrino Masses

Ernest Ma·G. Rajasekaran
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Abstract

The leptonic Higgs doublet model of neutrino masses is implemented with an A_4 discrete symmetry (the even permutation of 4 objects or equivalently the symmetry of the tetrahedron) which has 4 irreducible representations: 1, 1', 1'', and 3. The resulting spontaneous and soft breaking of A_4 provides a realistic model of charged-lepton masses as well as a nearly degenerate neutrino mass matrix. Phenomenological consequences at and below the TeV scale are discussed.

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Ernest Ma, G. Rajasekaran. 2001-06-26. Softly Broken A_4 Symmetry for Nearly Degenerate Neutrino Masses. https://doi.org/10.1103/physrevd.64.113012

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