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arXiv · 1012.1597

Early Universe effective theories: The Soft Leptogenesis and R-Genesis Cases

Abstract

We discuss the effective theory appropriate for studying soft leptogenesis at temperatures T>10^7 GeV. In this regime, the main source of the B-L asymmetry is the CP asymmetry of a new anomalous R-charge that couple to generalized anomalous electroweak processes. Baryogenesis thus occurs mainly through R-genesis, and with an efficiency that can be up to two orders of magnitude larger than in usual estimates. Contrary to common belief, a sizeable baryon asymmetry is generated also when thermal corrections to the CP asymmetries in sneutrino decays are neglected which, in soft leptogenesis, implyes vanishing lepton-flavour CP asymmetries. We present general Boltzmann equations for soft leptogenesis that are valid in all temperature regimes.

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Chee Sheng Fong, M. C. Gonzalez-Garcia, Enrico Nardi. 2010-12-07. Early Universe effective theories: The Soft Leptogenesis and R-Genesis Cases. https://doi.org/10.1088/1475-7516/2011/02/032

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