Polar Cap Boundary Phenomena [Paperback]

These proceedings are based on the invited talks and selected research reports presented at the NATO Advanced Study Institute (ASI) on POLAR CAP BOUNDARY PHENOMENA held at Longyearbyen, Svalbard, June 4 - 13, 1997. The role of the polar cap and its boundary is very substantial in solar-terrestrial physics. At this NATO AS! a major change in thinking on the cusp precipitation region in the high-latitude days ide upper atmosphere was reflected, at least for intervals when the interplanetary magnetic field (IMF) is directed southward. It is likely that this has implications for northward IMF as well. The change comes from the now almost complete acceptance of the concept of magnetosheath particle entry along open magnetic field lines and the evolution of the precipitation into the upper atmosphere with time elapsed since magnetic reconnection which opened the field line. A key prediction of this view is that the low-latitude boundary layer (LLBL) is on open field lines.Recent work on the Kelvin-Helmholtz instability at the dayside magnetopause and boundary layer.- Magnetopause motions in a Newton-Busemann approach.- Comparison of gasdynamics and MHD predictions for magnetosheath flow.- Time-varying reconnection. Quantitative reconnection.- An empirical model of the magnetopause for broad ranges of solar wind pressure and BZ IMF.- Solar wind He2+ and H+ distributions in the cusp for southward IMF.- Identifying the open-closed field line boundary.- Open and closed low latitude boundary layer.- The dynamic magnetosphere.- Ionospheric signatures of magnetopause processes.- Excitation of flow in the Earths magnetosphere-ionosphere system: observations by incoherent-scatter radar.- Large-scale electric fields in the dayside magnetosphere.- Polar observations of cusp electrodynamics: evolution from 2- to 4-cell convection patterns.- Relationship between large-, meso-, and small-scale field-aligned currents and their current carriers.- The dayside aurora and its regulatiolã$