Université Libre de Bruxelles
Friday, February 26, 2016 - 13:00
The Full Flavour of (Resonant) Leptogenesis
In this talk I discuss the mechanism of Resonant Leptogenesis (RL), which relates the generation of the observed Baryon Asymmetry of the Universe with low-energy neutrino physics, with a particular focus on the importance of flavour effects. In the first part, I will introduce the flavour-covariant formalism that allows a complete and consistent description of RL. In particular, a semiclassical flavour-covariant analysis allows the identification of three distinct pertinent phenomena: heavy-neutrino mixing, their oscillations and charged-lepton decoherence. The presence of these phenomena is confirmed in a fully field-theoretical approach. In the second part, I will discuss the related model-building and phenomenological aspects. I will first present a next-to-minimal low-scale model of RL, based on approximate Minimal Flavour Violation (MFV) and leptonic symmetries. I will show that this model has observable signatures in current and near-future experiments, and demonstrate the importance of flavour effects in this class of low-scale models. Later, I will discuss MFV leptogenesis, and show that the successful generation of the asymmetry entails combined mass bounds on the light and heavy neutrinos, and favours a normal hierarchy of the former. These results imply that the combination of the MFV hypothesis and successful leptogenesis can be almost completely tested at the MEG-II experiment.