Nonlinear dynamics, of large-amplitude circularly polarized Alfvénic wave packets, is investigated using a one-dimensional hybrid model. Kinetic effects such as finite-Larmor radius and nonlinear Landau damping, which become significant for plasmas with β∼ 1. are appropriately accounted for in these high-resolution hybrid simulations. Spatio-temporal evolution, of the left-hand polarized (LHP) wave packets, shows that they collapse because of the decreasing dispersive effects. However, singularities are arrested by the wave-particle interactions. At some critical time te, which depends on the plasma β and the initial amplitude of the wave packet, we observe a turning point. At this turning point, the polarization changes from LHP to RHP (right-hand polarized). The wave packet then starts broadening due to increasing dispersion associated with the RHP. Implications of collapse of the magnetic structures are briefly discussed.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics