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arXiv · hep-ph/9907400

Stability of Neutrino Mass Degeneracy

Ernest Ma
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Abstract

Two neutrinos of Majorana masses $m_{1,2}$ with mixing angle $θ$ are unstable against radiative corrections in the limit $m_1 = m_2$, but are stable for $m_1 = -m_2$ (i.e. opposite CP eigenstates) with $θ= 45^\circ$ which corresponds to an additional symmetry.

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Ernest Ma. 1999-07-25. Stability of Neutrino Mass Degeneracy. https://doi.org/10.1088/0954-3899%2F25%2F10%2F102

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