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arXiv · 1508.07930

Leptogenesis in an SU(5) x A5 Golden Ratio Flavour Model: Addendum

Abstract

We derive and discuss the solution of the Boltzmann equations for leptogenesis in a phenomenologically viable SU(5) x A5 golden ratio flavour model proposed in arXiv:1410.2057 [hep-ph], arXiv:1502.00110 [hep-ph] . The model employs, in particular, the seesaw mechanism of neutrino mass generation. We find that the results on the baryon asymmetry of the Universe, obtained earlier in arXiv:1502.00110 [hep-ph] using approximate analytic expressions for the relevant CP violating asymmetry and efficiency factors, are correct, as was expected, up to 20-30 %. The phenomenological predictions for the low energy neutrino observables, derived using values of the parameters of the model for which we reproduce the observed value of the baryon asymmetry, change little with respect to those presented in arXiv:1502.00110 [hep-ph]. Among the many predictions of the model we find, for instance, that the neutrinoless double beta decay effective Majorana mass m_ee lies between 3.3 meV and 14.3 meV.

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Julia Gehrlein, Serguey T. Petcov, Martin Spinrath, Xinyi Zhang. 2015-08-31. Leptogenesis in an SU(5) x A5 Golden Ratio Flavour Model: Addendum. https://doi.org/10.1016/j.nuclphysb.2015.08.019

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