Further study on the textures of neutrino mass matrix for maximal atmospherical mixing angle and Dirac CP phase.

In this paper, we derive in a novel approach the possible textures of neutrino mass matrix that can lead to maximal atmospherical mixing angle (θ23=π/4) and Dirac CP phase (δ=-π/2) in two phenomenologically appealing scenarios: (1) one neutrino mass matrix element vanishing (2) one neutrino mass vanishing. For the obtained textures, some neutrino mass sum rules that relate the neutrino masses and mixing parameters emerge. With the help of these sum rules, the unknown absolute neutrino mass scale and Majorana CP phases can be determined. Some discussions about the possible textures of neutrino mass matrix that can lead to θ23=π/4, δ=-π/2 and maximal Majorana CPphases (ρ, σ=π/4 or 3π/4) as well as the model realization and breakings of the obtained textures are also given. [ABSTRACT FROM AUTHOR]