Abstract

We present a test particle study of perturbations of a weakly relativistic electron distribution interacting with a rising-tone lower band chorus emission. Trajectories of interacting electrons are traced back in time from the equator to reconstruct the perturbed velocity distribution. The wave field is precalculated from a model based on the nonlinear growth theory and features a realistic subpacket structure. The perturbed distribution reveals a series of stripes of increased and decreased phase space density. This perturbation is associated with the electromagnetic hole structure which exists along the resonance velocity curve of each subpacket. Time-averaging of the final distribution shows that rising-tone lower band chorus emissions produce a sharp decrease in density at low parallel velocities, which might be detectable by spacecraft particle instruments.