2005/05/30 by T. Fujihara, S. Kaneko, Satoru Kaneko +7 · 5 citations
Physics and Astronomy · #Dark Matter and Cosmic Phenomena #Neutrino Physics Research #Particle physics theoretical and experimental studies #hep-ph
paper · pdf · doi:10.1103/physrevd.72.016006
published as Phys.Rev.D72:016006,2005 · 22 pages, 9 figures A figure caption corrected
arxiv created 2005/05/30 · openalex publication_date 2005/07/27 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We discuss how the cosmological baryon asymmetry can be achieved by the lepton family asymmetries of heavy Majorana neutrino decays and how the lepton family asymmetries are related to CP violation in neutrino oscillation, in the minimal seesaw model with two heavy Majorana neutrinos. We derive the most general formula for CP violation in neutrino oscillation in terms of the heavy Majorana masses and Yukawa mass term. It is shown that the formula is very useful to classify several models in which e, \ensuremathμ, and \ensuremathτ leptogenesis can be separately realized and to see how they are connected with low energy CP violation. To make the models predictive, we take texture with two zeros in the Dirac matrix. In particular, we find some interesting cases in which CP violation in neutrino oscillation can happen while lepton family asymmetries do not exist at all. On the contrary, we can find e-, \ensuremathμ-, and \ensuremathτ-leptogenesis scenarios in which the cosmological CP violation and low energy CP violation measurable via neutrino oscillations are very closely related to each other. By determining the allowed ranges of the parameters in the models, we predict the sizes of CP violation in neutrino oscillation and |Ve3MNS|. Finally, the leptonic unitarity triangles are reconstructed.