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arXiv · 1801.03937

Predictive Leptogenesis from Minimal Lepton Flavour Violation

Abstract

A predictive Leptogenesis scenario is presented based on the Minimal Lepton Flavour Violation symmetry. In the realisation with three right-handed neutrinos transforming under the same flavour symmetry of the lepton electroweak doublets, lepton masses and PMNS mixing parameters can be described according to the current data, including a large Dirac CP phase. The observed matter-antimatter asymmetry of the Universe can be achieved through Leptogenesis, with the CP asymmetry parameter $\varepsilon$ described in terms of only lepton masses, mixings and phases, plus two real parameters of the low-energy effective description. This is in contrast with the large majority of models present in the literature, where $\varepsilon$ depends on several high-energy parameters, preventing a direct connection between low-energy observables and the baryon to photon ratio today. Recovering the correct amount of baryon asymmetry in the Universe constrains the Majorana phases of the PMNS matrix within specific ranges of values: clear predictions for the neutrinoless double beta decay emerge, representing a potential smoking gun for this framework.

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BibTeXRIS

L. Merlo, S. Rosauro-Alcaraz. 2018-01-11. Predictive Leptogenesis from Minimal Lepton Flavour Violation. https://doi.org/10.1007/jhep07(2018)036

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