Magnetospheric Boundary Identification from Energetic Particle Measurements on Polar-Orbiting Satellites

点击翻译按钮获取中文摘要

We have determined that two important magnetospheric boundary regions on the side, the low-latitude boundary layer (LLBL) and the cusp, can be identified from energetic particle observations as well as from observations of magnetosheath-energy particle precipitation on polar-orbiting satellites. We propose to analyze simultaneous observations of magnetosheath energy particles obtained from the S3-3 satellite in order to identify these boundary regions, to analyze processes occurring within these boundary regions, and to investigate the mapping of these regions from the magnetosphere to the ionosphere. We will compare the identification obtined using the criteria developed be Newell and Meng ı1988! for magnetosheath-energy particles. In this way, we will investigate the accuracy of both techniques as well as determine the advantages of using energetic particle measurements to supplement and verify the identification obtainable using the Newell and Meng criteria. In addition, using the measured angular distributions of particles, we will investigate the extent to which the LLBL lies on closed field lines and estimate the locations of auroral acceleration regions relative to each of the magnetospheric boundary regions and to the open-closed field line boundary. We also propose to determine criteria for distinguishing between precipitation from the LLBL and that from the plasma sheet boundary layer. We will use the criteria to study the important transition between these two boundary layers as mapped to the ionosphere. Using the electric and magnetic field data from S3-3, we plan to study the spatial relations between the convection reversal, field-ligned currents, the different boundary regions, and the open-closed field line boundary. In this way, we hope to gain significant information on the extent to which the magnetospheric electric field is generated by reconnection versus viscous interaction and on the generation regions for day side field-aligned currents. Finally, using precipitation data from the identically instrumented, almost co-orbiting, DMSP F6 and F8 satellites, we will pursue the separation of temporal and spatial effects over latitudinal scale sizes as small as 10km within the day side boundary layers.