Tribimaximal neutrino mixing from discrete symmetry in extra dimensions
Abstract
We discuss a particularly symmetric model of neutrino mixings where, with good accuracy, the atmospheric mixing angle θ is maximal, θ=0 and the solar angle satisfies sinθ=1/3 (HarrisonPerkinsScott (HPS) matrix). The discrete symmetry A is a suitable symmetry group for the realization of this type of model. We construct a model where the HPS matrix is exactly obtained in a first approximation without imposing ad hoc relations among parameters. The crucial issue of the required VEV alignment in the scalar sector is discussed and we present a natural solution of this problem based on a formulation with extra dimensions. We study the corrections from higher dimensionality operators allowed by the symmetries of the model and discuss the conditions on the cutoff scales and the VEVs in order for these corrections to be completely under control. Finally, the observed hierarchy of charged lepton masses is obtained by assuming a larger flavour symmetry. We also show that, under general conditions, a maximal θ can never arise from an exact flavour symmetry.
 Publication:

Nuclear Physics B
 Pub Date:
 August 2005
 DOI:
 10.1016/j.nuclphysb.2005.05.005
 arXiv:
 arXiv:hepph/0504165
 Bibcode:
 2005NuPhB.720...64A
 Keywords:

 High Energy Physics  Phenomenology
 EPrint:
 24 pages, 1 figure, misprints corrected and references added