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A_4 Symmetry and Neutrinos with Very Different Masses

Ernest Ma
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Abstract

The A_4 model of leptons was proposed originally for nearly degenerate neutrino masses. With minimal modification, it is shown to accommodate as well the cases of normal hierarchy and inverted hierarchy. In all cases, this new model predicts sin^2 2 theta_{atm} = 1 and tan^2 theta_{sol} = 0.5 for U_{e3} = 0. It also predicts their deviations from 1 and 0.5 respectively for U_{e3} not equal to zero.

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Ernest Ma. 2004-09-07. A_4 Symmetry and Neutrinos with Very Different Masses. https://doi.org/10.1103/physrevd.70.031901

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