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arXiv · 0912.1787

Wash-Out in N_2-dominated leptogenesis

Florian Hahn-Woernle
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Abstract

We study the wash-out of a cosmological baryon asymmetry produced via leptogenesis by subsequent interactions. Therefore we focus on a scenario in which a lepton asymmetry is established in the out-of-equilibrium decays of the next-to-lightest right-handed neutrino. We apply the full classical Boltzmann equations without the assumption of kinetic equilibrium and including all quantum statistical factors to calculate the wash-out of the lepton asymmetry by interactions of the lightest right-handed state. We include scattering processes with top quarks in our analysis. This is of particular interest since the wash-out is enhanced by scatterings and the use of mode equations with quantum statistical distribution functions. In this way we provide a restriction on the parameter space for this scenarios.

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Florian Hahn-Woernle. 2009-12-09. Wash-Out in N_2-dominated leptogenesis. https://doi.org/10.1088/1475-7516/2010/08/029

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