Neutrino phenomenology and stable dark matter with A4

Understand

We present a model based on the A4 non-abelian discrete symmetry leading to a predictive five-parameter neutrino mass matrix and providing a stable dark matter candidate.

• We found an interesting correlation among the atmospheric and the reactor angles which predicts theta_23 ~ pi/4 for very small reactor angle and deviation from maximal atmospheric mixing for large theta_13.
• Only normal neutrino mass spectrum is possible and the effective mass entering the neutrinoless double beta decay rate is constrained to be |m_ee| > 4 10^{-4} eV.