“4321” Models: Neutrinos and Gravitational Wave Probes

Tuesday, 19 November 2019 at 11:15, in Y16 G05 - Campus Irchel

So-called "4321" models, providing third family quark-lepton unification and a UV completion for the Pati-Salam leptoquark at the TeV scale, offer what is to date the most coherent explanation for current flavor anomalies. However, such models suffer from a neutrino mass catastrophe resulting from the model predicting a 3rd-generation neutrino with the same mass as its SU(4)-multiplet partner, the top quark. I will show how this crisis can be naturally averted with the addition of fermionic singlets that allow the inverse seesaw mechanism (a low-scale solution for neutrino masses) to be implemented. Futhermore, CP-violating coherent oscillations of the heavy pseudo-Dirac pairs predicted by the ISS mechanism can be exploited to generate the baryon asymmetry of the universe at temperatures near the electroweak scale. Finally, using the Pati-Salam-Cubed model as an example, I discuss how models that associate flavor with a fundamental gauge symmetry at energies well beyond the reach of colliders can potentially be probed via a multi-peaked gravitational wave signature that is emitted as the gauge symmetry is broken in several hierarchical steps.