DISSIPATIVE DYNAMICS OF COLLISIONLESS NONLINEAR ALFVEN-WAVE TRAINS

The nonlinear dynamics of collisionless Alfven trains. including reson ant particle effects, is studied using the kinetic nonlinear Schroding er (KNLS) equation model. Numerical solutions of the KNLS reveal the d ynamics of Alfven waves to be sensitive ro the sense of polarization a s well as the angle of propagation with respect to the ambient magneti c field. The combined effects of both wave nonlinearity and Landau dam ping resulting the evolutionary formation of stationary S- and arc-pol arized directional and rotational discontinuities. These wave forms ar e frequently observed in the interplanetary plasma.