Efficient numerical integration of neutrino oscillations in matter
  A special purpose solver, based on the Magnus expansion, well suited for the integration of the linear three neutrino oscillations equations in matter is proposed. The computations are speeded up to two orders of magnitude with respect to a general numerical integrator, a fact that could smooth the way for massive numerical integration concomitant with experimental data analyses. Detailed illustrations about numerical procedure and computer time costs are provided. 
Fernando Casas, Jose Angel Oteo and Juan Carlos D'Olivo
physics.comp-ph hep-ph math.NA