A quantitative model of the magnetosphere with poloidal vector fields

Abstract. A quantitative model of the magnetospheric magnetic field is developed using poloidal vector fields. This formalism is applied to the ring current region, the distant field and the return currents. The tail model is similar to the unwarped model of Tsyganenko. Several sets of coefficients are obtained for different Kp through a fit of the NSSDC data base. Experimental ΔB contours and theoretical distributed currents contours are correctly described and are Kp-dependent. Field line topology problems and poor ring current description observed in models of similar complexity are avoided. Computer time has been kept reasonable and makes this model particularly adapted to intensive-type calculations.

Key words. Magnetospheric physics (magnetospheric · configuration and dynamics).