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arXiv · 0909.2836

On the Interplay Between the 'Low' and 'High' Energy CP-Violation in Leptogenesis

E. Molinaro·S. T. Petcov
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Abstract

The CP-violation necessary for the generation of the baryon asymmetry of the Universe in the "flavoured" leptogenesis scenario can arise from the "low energy" PMNS neutrino mixing matrix and/or from the "high energy" part of neutrino Yukawa couplings, which can mediate CP-violating phenomena only at some high energy scale. The possible interplay between these two types of CP-violation is discussed. The type I see-saw model with three heavy right-handed Majorana neutrinos having hierarchical spectrum is considered. The analysis shows that there exist regions in the leptogenesis parameter space where the relevant "high energy" phases have large CP-violating values, but the purely "high energy" contribution to the baryon asymmetry plays a subdominant/suppressed role in the production of baryon asymmetry compatible with the observations and one can have successful leptogenesis if the requisite CP-violation is provided by the Majorana phase(s) in the neutrino mixing matrix.

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E. Molinaro, S. T. Petcov. 2009-09-15. On the Interplay Between the 'Low' and 'High' Energy CP-Violation in Leptogenesis. https://arxiv.org/abs/0909.2836

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