Test kinetic modelling of collisionless perpendicular shocks

Test kinetic simulation results are presented for perpendicular collisionless shocks in magnetized plasmas that are representative of the Earth's bow shock. In this approach, particle kinetics are described by tracing particle trajectories in prescribed electromagnetic fields obtained in the MHD approximation, and applying Liouville's theorem. This provides a first-order description of particle dynamics in complex systems, given approximate fields obtained with a low-level description of the plasma. The method also provides a useful consistency check in assessing the validity of approximate solutions such as those obtained in the ideal MHD approximation. Compared with the more familiar test particle approach, in which trajectories of randomly injected particles are followed in time, the present approach has the advantage of being numerically more efficient, and producing results without statistical errors.