Ion and neutral polar winds for northward interplanetary magnetic field conditions

The coupling of the ionosphere/magnetosphere system at high-latitudes is dependent in part upon the transport of neutral atoms from the ionosphere to the magnetosphere, and visa versa. The neutral atoms that flow between the ionosphere and the magnetosphere are neutral stream atoms that are produced in charge exchange reactions between the ions in the polar wind and the background thermal and geocoronal atoms. The characteristics of these neutral stream particles are highly dependent upon the ions in the polar cap. The ions are convected across the polar cap due to convection electric fields, and thus the neutral stream particles are also indirectly affected by the convection electric fields due to charge exchange. The horizontal flow of neutral stream particles, therefore, shows a general anti-sunward motion during periods of southward interplanetary magnetic field (IMF), and a general sunward flow across the magnetic pole during times of northward IMF. The vertical fluxes of these neutral stream particles depend upon several processes, including the heat input due to precipitating electrons, the vertical velocity of the ions involved in the charge exchange reactions that produce the neutral stream particles, and the time history of neutral stream particles in the high-latitude region.