Flavoured Leptogenesis in the CTP Formalism

Understand

Within the Closed Time Path (CTP) framework, we derive kinetic equations for particle distribution functions that describe leptogenesis in the presence of several lepton flavours.

• These flavours have different Standard-Model Yukawa couplings, which induce flavour-sensitive scattering processes and thermal dispersion relations.
• Kinetic equilibrium, which is rapidly established and maintained via gauge interactions, allows to simplify these equations to kinetic equations for the matrix of lepton charge densities.
• In performing this simplification, we notice that the rapid flavour-blind gauge interactions damp the flavour oscillations of the leptons.