NATURALLY PERTURBED S3 NEUTRINOS

Naturally degenerate neutrinos

The solar neutrino problem, atmospheric neutrino problem and the hot dark matter which seems to be required by galaxy formation can all be most economically described by three very degenerate neutrinos with a common mass of a few eV. Such neutrino masses could also be relevant for the recent data on double beta decay. We provide an existence proof for such a scenario by constructing an explicit...

Naturally light sterile neutrinos

A simple model to accomodate light sterile neutrinos naturally with large mixing with the usual neutrinos has been proposed. The standard model gauge group is extended to include an SU(2)S gauge symmetry. Heavy triplet higgs scalars give small masses to the lefthanded neutrinos, while a heavy doublet higgs scalar give mixing with the sterile neutrinos of the same order of magnitude. The neutrin...

Naturally Degenerate Right Handed Neutrinos

In the context of supersymmetric theories, a weakly broken gauged SO(3) flavour symmetry is used to produce two highly degenerate right handed (RH) neutrinos. It is then shown that this SO(3) flavour symmetry is compatible with all fermion masses and mixings if it is supplemented with a further SU(3) flavour symmetry. A specific Susy breaking model is used to generate the light neutrino masses ...

Framework for Naturally Light Singlet Neutrinos

The totality of present neutrino data seems to require four light neutrinos, but only three of them can be the neutral components of left-handed lepton doublets. To accommodate one or more naturally light singlet neutrino(s), an extra U(1) gauge factor is proposed to implement an analogous seesaw mechanism which accounts for the light doublet neutrinos. Using the constraints of anomaly cancella...

Doubly Perturbed S_3 Neutrinos and the s_{13} Mixing Parameter