Alfven Turbulence Driven by High-Dimensional Interior Crisis in the Solar Wind

摘要

Alfven intermittent turbulence has been observed in the solar wind. It has been previously shown that the interplanetary Alfven intermittent turbulence can appear due to a low-dimensional temporal chaos. In this paper, we study the nonlinear spatiotemporal dynamics of Alfven waves governed by the Kuramoto-Sivashinsky equation which describes the phase evolution of a large-amplitude Alfven wave. We investigate the Alfven turbulence driven by a high-dimensional interior crisis, which is a global bifurcation caused by the collision of a chaotic attractor with an unstable periodic orbit. This nonlinear phenomenon is analyzed using the numerical solutions of the model equation. The identification of the unstable periodic orbits and their invariant manifolds is fundamental for understanding the instability, chaos and turbulence in complex systems such as the solar wind plasma. The high-dimensional dynamical system approach to space environment turbulence developed in this paper can improve our interpretation of the origin and the nature of Alfven turbulence observed in the solar wind.