Implications of δlCP~270° and θ23≳45∘ for Texture Specific Lepton Mass Matrices and 0νββ Decay

Abstract

We study the phenomenological consequences of recent results from atmospheric and accelerator neutrino experiments, favoring normal neutrino mass ordering m1<m2<m3, a near maximal lepton Dirac CP phase δl~270∘ along with θ23≳45∘, for possible realization of natural structure in the lepton mass matrices characterized by (Mij)~O(mimj) for i,j=1,2,3. It is observed that deviations from parallel texture structures for Ml and Mν are essential for realizing such structures. In particular, such hierarchical neutrino mass matrices are not supportive for a vanishing neutrino mass mν1→0 characterized by Det Mν≠0 and predict mν1≃(0.1–8.0) meV, mν2≃(8.0–13.0) meV, mν3≃(47.0–52.0) meV, Σ≃(56.0–71.0) meV, and 〈mee〉≃(0.01–10.0) meV, respectively, indicating that the task of observing a 0νββ decay may be rather challenging for near future experiments.