A new model for the topology of magnetic clouds in the solar wind

We present a model that describes the topology of a magnetic cloud. The model relates the magnetic field vector and current density of the cloud without assuming the force-fret condition. Fitting the model to the experimental data we obtain the current density, the attitude of the axis and the relative closest-approach distance between the spacecraft and the cloud axis. In this paper, several magnetic clouds of 1997 are analyzed. The results indicate that the topology presented in this paper explains the magnetic field inside a MC better than force-free models. A current density of the order of 10(-12) C m(-2) s(-1) is obtained in the fitting of all the events.