Nonlinear Study of Wave Packets in Space Plasma

University Of California-San Diego, La Jolla CA

Investigators

Abstract

The goal of this investigation is to explain the fascinating solar wind observations that reveal the existence of sunward-propagating Alfven fluctuations and rotational/directional discontinuities in the solar wind plasma. Combined numerical and analytical methods will be used to describe the nonlinear interactions of Alfven wave packets traveling in opposite directions along an ambient magnetic field. The model will incorporate, (i) parametric interaction of harmonics propagating in the same direction, that is responsible for steepening and the cascade of wave energy, (ii) sunward-bound waves of finite amplitude. A self-consistent treatment including the nonlinear dynamics of resonant particles will be carried out, in order to account for the creation of collisionless dissipative structures through the strong proton Landau damping of ion-acoustic quasi-modes.