Bimaximal Mixing in an SO(10) Minimal Higgs Model

TL;DR

This paper discusses a minimal SO(10) SUSY GUT model that naturally produces bimaximal neutrino mixing, aligning with atmospheric and solar neutrino data, and explores how slight modifications can improve the fit.

Contribution

It introduces a minimal Higgs model that achieves bimaximal neutrino mixing through a small modification, enhancing previous quark and lepton mass matrix fits.

Findings

Bimaximal mixing for atmospheric and solar neutrinos achieved.

Slight modification leads to non-zero up quark mass and improved neutrino mixing.

The 'just-so' vacuum solution is slightly favored over the large-angle MSW solution.

Abstract

An SO(10) SUSY GUT model was previously presented based on a minimal set of Higgs fields. The quark and lepton mass matrices derived fitted the data extremely well and led to large mixing of muon- and tau-neutrinos in agreement with the atmospheric neutrino data and to the small-angle MSW solution for the solar neutrinos. Here we show how a slight modification leading to a non-zero up quark mass can result in bimaximal mixing for the atmospheric and solar neutrinos. The "just-so" vacuum solution is slightly favored over the large-angle MSW solution on the basis of the hierarchy required for the right-handed Majorana matrix and the more nearly-maximal mixing angles obtained.