Type: Article
Publication Date: 2013-04-11
Citations: 5
DOI: https://doi.org/10.1103/physrevd.87.075008
Supersymmetric SO(10) grand unified models with renormalizable Yukawa couplings involving 10, 126, and 120 Higgs fields have been shown to give a very economical theory for understanding quark-lepton flavor in a unified framework. In previous papers, we showed how nucleon decay can be suppressed in these models without invoking cancellation, by choice of Yukawa flavor texture within a type II seesaw framework for neutrinos that explains all mixings and masses including the recently observed ``large'' ${\ensuremath{\theta}}_{13}$. In this followup paper, we extend our earlier work to the case of type I seesaw and show that the recently measured large ${\ensuremath{\theta}}_{13}$ can be accommodated in this case while suppressing proton decay. We then point out that the two cases (type I and II) lead to different testable predictions for $B(\ensuremath{\mu}\ensuremath{\rightarrow}e+\ensuremath{\gamma})$ and $B(\ensuremath{\tau}\ensuremath{\rightarrow}\ensuremath{\mu}(e)+\ensuremath{\gamma})$ as well as different flavor final states in nucleon decay. In particular, we find that for the type I seesaw case, $B(\ensuremath{\tau}\ensuremath{\rightarrow}\ensuremath{\mu}+\ensuremath{\gamma})$ can be observable while at the same time suppressing $B(\ensuremath{\mu}\ensuremath{\rightarrow}e+\ensuremath{\gamma})$, whereas in the type II seesaw case, $B(\ensuremath{\tau}\ensuremath{\rightarrow}\ensuremath{\mu}+\ensuremath{\gamma})$ is always suppressed whereas $B(\ensuremath{\mu}\ensuremath{\rightarrow}e+\ensuremath{\gamma})$ is observable.