PLASMA PHENOMENA IN THE EARTHS NEAR SPACE ENVIRONMENT

The proposal addresses parts of the STAR-project at the Department of Physics, University of Oslo. One of the basic problems addressed by the STAR-project is analysis and interpretation of data from instrumented spacecrafts. We propose a study of plasma p henomena in the Earths near and also more distant space environments. A different application will deal with the hard-ware part of the project, together with the ground-based activity.One subproject is a topic with space weather applications: probing of solar wind - magnetosphere - ionosphere interaction processes during Earth passage of interplanetary (IP) magnetic clouds.Recently suggested specific modes of solar wind - magnetospherecoupling (reconnection) will be tested by a combination of ground an d satellite observations during intervals when the Earths magnetosphere is forced by the huge magnetic flux ropes ofIP magnetic clouds.A major enterprise within the STAR-project right now is the ICI2 rocket to be launched December 2008, with expected al titude of 350 km. The instruments are designed for studying electrostatic fluctuations in the Earths northern Cusp-region. We expect that the launch of ICI2 will be the first in a series, spanning some ten years of time, where the group will systematicall y extend the studies of the Cusp. The methods and numerical tools being developed will have generalapplicability, and will be applied also to other data, from the Freja satellite for instance, where previous studies of lower-hybrid wave cavities have been well received. These extended studies will include Langmuir wave phenomena that are also frequently observed by Freja.Most of the data are obtained by use of Langmuir probes. For non-equilibrium plasmas, for instance in the presence of UV-radiation, ion or electron beams, the results are not readily interpreted. We propose development of numerical plasma simulations for analyzing probe performances under nonequilibrium conditions.