Weak Scale Baryogenesis in a Supersymmetric Scenario with R-parity violation

We investigate the connection between R-parity violation (RPV) in supersymmetric mod-els and Baryogenesis. First we discuss in detail the assumptions of a theorem by Nanopoulos and Weinberg on the CP asymmetry generated from the decay of massive particles. In light of this statement, we analyse some interesting models of Baryogenesis through RPV. We then explore, in the context of RPV SUSY, the possibility to generate the baryon asymmetry through the out-of-equilibrium decay of a metastable Weakly Interacting Massive Particle (WIMP), as proposed in [1]. This setting is also motivated by the observed coincidence be-tween the abundances of dark and baryonic matter. In this framework, we propose two models of out-of-equilibrium decay of a would-be cold relic, and compute the associated CP asym-metry. With a TeV-scale parent, the observed baryon abundance can be reproduced in these models when the stop is in the multi-TeV region. Furthermore, annihilation of the metastable particle into SM states must be characterised by a very weak coupling, g ∼ 10−2 and by a heavy mediator mmed ∼ 10 TeV. These models can also accommodate stop masses far from the TeV scale, at the expense of weakening the explanation of the ΩB − ΩDM coincidence. ar X i