GeV-scale hot sterile neutrino oscillations: a numerical solution

Understand

The scenario of baryogenesis through GeV-scale sterile neutrino oscillations is governed by non-linear differential equations for the time evolution of a sterile neutrino density matrix and Standard Model lepton and baryon asymmetries.

• By employing up-to-date rate coefficients and a non-perturbatively estimated Chern-Simons diffusion rate, we present a numerical solution of this system, incorporating the full momentum and helicity dependences of the density matrix.
• The density matrix deviates significantly from kinetic equilibrium, with the IR modes equilibrating much faster than the UV modes.
• For equivalent input parameters, our final results differ moderately (~50%) from recent benchmarks in the literature.