A coupled-map model for the magnetotail current sheet

A magnetic field model of the magnetotail current sheet in the form of a co upled-map lattice (CML) is presented. It is a continuously driven and based on the MHD diffusion equation. Solar wind vB(S) data (solar wind speed mul tiplied by the southward component of IMF) are used for driving the model, and it is shown to exhibit perturbations (avalanches) with power-law scalin gs in their distributions of duration and size. Such distributions may indi cate self-organized critical (SOC) behavior. Furthermore, it is shown that the power spectra of the model outputs are of bicolor power-law form with d ifferent slopes for high and low frequencies. The model parameters determin e the frequency of the break points of the spectra, and the slopes of their low and high frequency regimes.