Imaging the plasmasphere and trough regions in the extreme-ultraviolet region

Abstract

EUV images from emissions of O⁺ (83.4 nm) and He⁺ (30.4 nm) distributions in the plasmasphere and trough regions are constructed for a satellite at 9 <i>Re</i> (where <i>Re</i> is Earth radii). A diffusive equilibrium model is used to describe the density distribution along the field lines for ions in the plasmasphere, and a kinetic collisionless model is assumedto calculate ion densities in the high-latitude regions beyond the plasmapause. In our model ofthe plasmasphere, we assumethat ions move along astatic dipole field. Observational data on O⁺ and He⁺ densities in the ionosphere are used as boundaryconditionsto calculatethespatial distribution of densities along the field lines. Assuming thatthe day and night boundary conditions are asymmetric and exobase densities vary with latitude, we discuss how this would be reflected in the intensities and structure of the magnetospheric images.