Finite Temperature Stabilization of the Gradient Drift Instability in Barium Clouds

摘要

The study of the dynamic evolution of artificial plasma clouds (e.g., barium clouds) in the earth's ionosphere and magnetosphere has been an active area of research for more than two decades. The initial motivation for these active space experiments was to use the plasma cloud as a diagnostic to determine ambient plasma conditions (e.g., electric fields, neutral winds). It was discovered that the interaction of an artificial plasma cloud and the near-earth space plasma was very complex, and that plasma clouds undergo a complicated and dynamic evolution. One of the prominent features of cloud evolution in the ionosphere is the development of field-aligned striations on the cloud's steepened 'backside'. These striations have been attributed to the onset of the gradient drift instability. This instability can occur in a weakly collisional plasma which contains a density gradient and a neutral wind (or ambinet electric field.