Kinetic Properties of Mesoscale Plasma Injections

Convection and acceleration of plasma in the magnetotail is comprised of mesoscale activations localized in the azimuthal extent to several Earth radii. According to spacecraft observations mesoscale injections can be accompanied by a complex chain of interactions cascading down to microscales, from kinetic Alfven waves to whistler chorus waves and time-domain structures. The goal of this study is to investigate the types and the growth rates of energetic plasma instabilities at injection fronts. For this purpose we employ test-particle simulations using our Conservative Hamiltonian Integrator of Magnetospheric Particles (CHIMP) with high-resolution MHD simulations of plasma convection in the magnetotail. For the later we use the Lyon-Fedder-Mobarry (LFM) global magnetospheric model. Spatial and temporal evolution of the phase space density of energetic plasma at the injection fronts are computed from test-particle trajectories and then used to assess the pitch-angle anisotropy parameters and search for phase-space structures such as beams and boundary layers.