Testing solar lepton mixing sum rules in neutrino oscillation experiments

Understand

Small discrete family symmetries such as S4, A4 or A5 may lead to simple leading-order predictions for the neutrino mixing matrix such as the bimaximal, tribimaximal or golden ratio mixing patterns, which may be brought into agreement with experimental data with the help of corrections from the charged-lepton sector.

• Such scenarios generally lead to relations among the parameters of the physical leptonic mixing matrix known as solar lepton mixing sum rules.
• In this article, we present a simple derivation of such solar sum rules, valid for arbitrary neutrino and charged lepton mixing angles and phases, assuming only {\theta}13^{\nu} = {\theta}13^e = 0.
• We discuss four leading-order neutrino mixing matrices with {\theta}13^{\nu} = 0 which are well motivated from family symmetry considerations.