Conjugate studies of whistler-mode waves in the Van Allen radiation belts

Whistler-mode waves, especially chorus, can influence energetic electrons in the Van Allen radiation belts. These electromagnetic waves propagate over long distances in the magnetosphere. It has been previously shown that chorus can propagate from its equatorial source down to the subauroral ionosphere. We investigate cases where whistler-mode waves were simultaneously measured by the Cluster spacecraft in the magnetosphere and by the low-orbiting Demeter spacecraft. Multicomponent measurements of both these spacecraft missions allow us to investigate the wave-vector directions and Poynting flux. We can therefore show conjugate propagation properties of the waves in two different magnetospheric regions.