Leptogenesis from low energy CP violation

  • K. MoffatEmail author
  • S. Pascoli
  • S. T. Petcov
  • J. Turner
Open Access
Regular Article - Theoretical Physics


We revisit the possibility of producing the observed baryon asymmetry of the Universe via thermal leptogenesis, where CP violation comes exclusively from the low-energy phases of the neutrino mixing matrix. We demonstrate the viability of thermal flavoured leptogenesis across seven orders of magnitude (106< T (GeV) < 1013), using modern numerical machinery, where the lower bound can be reached only if flavour effects are taken into account and its value depends on the allowed degree of cancellation between the tree-level and radiative contributions to the light neutrino masses. At very high scales (T ≫1012 GeV), we clarify that thermal leptogenesis is sensitive to the low-energy phases, in contradiction with what is usually claimed in the literature. In particular we demonstrate that Majorana-phase leptogenesis is in general viable while Dirac-phase leptogenesis requires some level of fine-tuning.


CP violation Neutrino Physics Beyond Standard Model 


Open Access

This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited.


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© The Author(s) 2019

Authors and Affiliations

  1. 1.Institute for Particle Physics Phenomenology, Department of PhysicsDurham UniversityDurhamU.K.
  2. 2.SISSA/INFNTriesteItaly
  3. 3.Kavli IPMU (WPI)University of TokyoKashiwaJapan
  4. 4.Theoretical Physics DepartmentFermi National Accelerator LaboratoryBataviaU.S.A.

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