Self-Organization and hysteresis in a simple plasma model

The study of self-organization (SO) and its relation with turbulence is a subject at the forefront of astrophysics and space research, and in particular, it may have relevance in the behavior of the magnetospheric environment. We will study the intermittent energy dissipation in a simple plasma models of a current sheet induced by a localized instability with a hysteretic dissipation loop. The multi-state behavior present in this model seems to occur naturally in complex systems, and is of particular relevance for the existence of a out-of-equilibrium globally stable state with underlying turbulent behavior. The complex behavior of this system will be studied using the techniques that are being developed for spatio-temporal chaotic dynamics. In the case of the magnetotail, this self-organized state [Chang 1998] is necessary to bridge the two seemingly contradicting observations. While the magnetotail plasma sheet appears to be a dynamic and turbulent region [Borovsky et al., 1997], the magnetotail activity seems to be predictable [Vassiliadis et al., 1995], repeatable and globally coherent [Baker et al., 1998] as characterized by its different phases.