High and low frequency large amplitude variations of plasma and magnetic field in the magnetosheath: Radial profile and some features

Variations in magnetosheath parameters, such as the ion flux and the magnitude of the magnetic field, over a wide range of frequencies are much larger than the variations in the undisturbed solar wind. We present the results of a statistical investigation of magnetosheath variations using a large database of high time resolution (ls) INTERBALL-1 measurements and 1 min resolution IMP 8 data. Radial profiles of the ion flux and the standard deviations of the ion flux on 1-minute intervals were obtained for dusk and dawn flanks of the magnetosheath. These profiles are similar on the dawn and dusk flanks of the magnetosheath and for high and low frequency variations. The amplitude of the high frequency variations depends on the angle between the bow shock normal and interplanetary magnetic field direction; variations are much larger behind quasi-parallel bow shocks.