New class of SO(10) models for flavor

We present a new class of unified models based on SO (10) symmetry which provides insights into the masses and mixings of quarks and leptons, including the neutrinos. The key feature of our proposal is the absence of the Higgs boson 10₇ belonging to the fundamental representation that is normally employed. Flavor mixing is induced via vectorlike fermions in the 16+16 representation. A variety of scenarios, both supersymmetric and otherwise, are analyzed involving a 126₇ along with either a 45₇ or a 210₇ of the Higgs boson employed for symmetry breaking. It is shown that this framework, with only a limited number of parameters, provides an excellent fit to the full fermion spectrum, utilizing either the type-I or type-II seesaw mechanism. These flavor models can be potentially tested and distinguished in their predictions for proton decay branching ratios, which are analyzed.