Abstract

The azimuthal distribution of magnetospheric plasma pressure was studied using the precipitating particle fluxes observed by the low-altitude polar-orbiting Aureol-3 satellite. The data from the 18 March 1982 event was used to calculate the pressure along the satellite trajectory during quiet geomagnetic conditions. The magnetic flux tube volumes for the field-lines, corresponding to the points of measurement at the satellite trajectory, were calculated by using Tsyganenko 96 magnetic-field model. The gradients of the plasma pressure along the isosurfaces of the volume of the magnetic flux tube per unit flux were estimated, and the field-aligned currents were calculated assuming that the condition of the magnetostatic equilibrium is valid. The results obtained were compared with the [J. Geophys. Res. 81 (13) (1976) 2165] field-aligned current distribution. © 2003 COSPAR. Published by Elsevier Ltd. All rights reseved.