Non-vanishing image and image from a broken image symmetry Original Research Article

It is shown that the neutrino mass matrices in the flavour basis yielding a vanishing image are characterized by invariance under a class of image symmetries. A specific image in this class also leads to a maximal atmospheric mixing angle image. The breaking of that image can be parameterized by two dimensionless quantities, ε and image; the effects of image are studied perturbatively and numerically. The induced value of image strongly depends on the neutrino mass hierarchy. We find that image is less than 0.07 for a normal mass hierarchy, even when image. For an inverted mass hierarchy image tends to be around 0.1 but can be as large as 0.17. In the case of quasi-degenerate neutrinos, image could be close to its experimental upper bound 0.2. In contrast, image can always reach its experimental upper bound 0.28. We propose a specific model, based on electroweak radiative corrections in the MSSM, for ε and image. In that model, both image and image, could be close to their respective experimental upper bounds if neutrinos are quasi-degenerate.