Modeling the Evolution of Chorus Waves into Hiss Waves in the Magnetosphere

In this study, we analyze Cluster observations of whistler-mode chorus and hiss waves during the event of August 19-21, 2006. Chorus is present outside the plasmasphere and hiss occurs inside the plasmasphere. Using a recently constructed plasma boundary layer model, we perform a ray-tracing study on the propagation of chorus. Numerical results show that chorus can penetrate into the plasmasphere through the plasma boundary layer, evolving into hiss. The current data analysis and modeling provide a further observational support for the previous findings that chorus is the origin of plasmaspheric hiss.