IMAGING THE PLASMASPHERE AND TROUGH REGIONS IN THE EXTREME-ULTRAVIOLET REGION

EUV images from emissions of O+ (83.4 nm) and He+ (30.4 nm) distributi ons in the plasmasphere and trough regions are constructed for a satel tite at 9 R(e) (where R(e) is Earth radii). A diffusive equilibrium mo del is used to describe the density distribution along the field lines for ions in the plasmasphere, and a kinetic collisionless model is as sumed to calculate ion densities in the high-latitude regions beyond t he plasmapause. In our model of the plasmasphere, we assume that ions move along a static dipole field. Observational data on O+ and He+ den sities in the ionosphere are used as boundary conditions to calculate the spatial distribution of densities along the field lines. Assuming that the day and night boundary conditions are asymmetric and exobase densities vary with latitude, we discuss how this would be reflected i n the intensities and structure of the magnetospheric images.