Solar Terrestrial Coupling Through Space Plasma Processes

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project investigates plasma processes that govern the interaction between the solar wind, charged particles ejected from the sun, and the earth’s magnetosphere, the region above the ionosphere governed by the terrestrial magnetic field. Primary regions of interest are the regions where different plasma populations interact with each other. These are regions of particularly dynamic plasma behavior, associated with magnetic flux and energy transfer and dynamic energy release. The investigations concerned charged particle transport and energization, and microscopic and macroscopic instabilities in the magnetosphere and adjacent regions. The approaches combined space data analysis with theory and computer simulations. Background and Research Objectives The earth’s magnetosphere is defined as its charged particle (plasma) environment above the ionosphere governed by the terrestrial magnetic field. The magnetosphere is shaped and strongly controlled by its interaction with the solar wind, a charged particle stream ejected from the sun. The magnetosphere occupies a region of roughly 10 to 15 earth radii above the surface on the dayside and extends into a long tail, like a comet’s tail, of hundreds of earth radii length on the nightside. The major regions are shown schematically in Fig. 1. Dynamic processes that involve the coupling between the two plasmas cause the spectacular auroras (polar lights), I?U33EIVED *Principal Investigator, e-mail: [email protected] DEC 1 321MI