Ionospheric signatures of internal reconnection for northward interplanetary magnetic field: Observation of “reciprocal cells” and magnetosheath ion precipitation

摘要: [1] Magnetic reconnection that involves overdraped lobe field lines is called internal since it occurs inside the magnetopause. When interplanetary magnetic (IMF) due northward and Earth's dipole tilted significantly, in winter hemisphere, not only between a summer line but also closed line. The latter drives “reciprocal cells” ionosphere circulate exclusively region. reciprocal cells are intimately related to steady state, voltage associated with merging of IMF open equal sum cell potential potential. In this paper we present observations convection patterns consistent those expected for cells, using ionospheric radar low-altitude satellite data. We show concurrence cells. provide support addition, equatorward polar cap boundary, magnetosheath-like ions drifting from noon toward flankside both hemispheres. suggest these magnetosheath origin they entered region magnetosphere through rotational discontinuity reconnection. These ion strongly occurrence