Three-dimensional numerical simulation of ion and electron accelerations by parametric decay of fast lower hybrid waves

Summary form only given. The transverse acceleration of ions by fast lower hybrid waves in the topside auoral ionosphere has remained elusive. The linear and nonlinear propagation and evolution of lower hybrid waves are essentially a three-dimensional problem. Analytical treatment of this problem, including the essential kinetic effects for particle acceleration, is a formidable task if not impossible. We have treated this problem by a fully three-dimensional particle-in-cell simulation. It is found that a fast lower hybrid pump wave undergoes a parametric decay generating secondary waves over a broad frequency range from the ion cyclotron frequency /spl Omega//sub i/ to just above the lower hybrid frequency /spl omega//sub lh/. These secondary waves are instrumental in the accelerations of both cold ions and electrons. The ion acceleration is predominantly perpendicular to the ambient magnetic field (B), and it is accompanied by a relatively weak parallel acceleration in the direction of the phase velocity of the pump wave V/sub p/spl par/o/.