CP Violation in Predictive Neutrino Mass Structures

Original · EN

We study the CP violation effects from two types of neutrino mass matrices with (i) (Mν)ee=0, and (ii) (Mν)ee=(Mν)ₑμ=0, which can be realized by the high dimensional lepton number violating operators ℓᵣᶜγμLₗ (DμΦ)Φ² and ℓᵣᶜ lᵣ (DμΦ)²Φ², respectively. In (i), the neutrino mass spectrum is in the normal ordering with the lightest neutrino mass within the range 0.002 eV m₀ 0.007 eV. Furthermore, for a given value of m₀, there are two solutions for the two Majorana phases α₂₁ and α₃₁, whereas the Dirac phase δ is arbitrary. For (ii), the parameters of m₀, δ, α₂₁, and α₃₁ can be completely determined. We calculate the CP violating asymmetries in neutrino-antineutrino oscillations for both mass textures of (i) and (ii), which are closely related to the CP violating Majorana phases.