Sökning: "plasma convection"

Visar resultat 1 - 5 av 22 avhandlingar innehållade orden plasma convection.

1. 1. Substorm Features in the High-Latitude Ionosphere and Magnetosphere : Multi-Instrument Observations

   Författare :Eva Borälv; Hermann Opgenoorth; Mark Lester; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; Substorm; Convection; magnetosphere-ionosphere coupling; Rymd- och plasmafysik; Space physics; Rymdfysik; Space and Plasma Physics; rymd- och plasmafysik;

   Sammanfattning : The space around Earth, confined in the terrestrial magnetosphere, is to some extent shielded from the Sun's solar wind plasma and magnetic field. During certain conditions, however, strong interaction can occur between the solar wind and the magnetosphere, resulting in magnetospheric activity of several forms, among which substorms and storms are the most prominent. LÄS MER

3. 2. Global Magnetospheric Plasma Convection

   Författare :Stefan Eriksson; KTH; []
   Nyckelord :Geophysics; satellite measurements; electric fields; magnetosphere; magnetic reconnection;

   Sammanfattning : This thesis deals with the global aspects of plasmaconvection in the magnetosphere as measured by the low-altitudepolar orbiting Astrid-2 and FAST satellites. The major focus ison the electric field measurements, but they are alsocomplemented by magnetic field, ion and electron particle data,which is fundamental for the understanding of theelectrodynamics of the high-latitude auroral ovals and polarcap, which are the regions analysed here. LÄS MER

4. 3. Plasma and dust interaction in the magnetosphere of Saturn

   Författare :Jonas Olson; Svetlana Ratynskaia; Carmine Castaldo; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; saturn; dusty plasma;

   Sammanfattning : The Cassini spacecraft orbits Saturn since 2004, carrying a multitude of instruments for studies of the plasma environment around the planet as well as the constituents of the ring system. Of particular interest to the present thesis is the large E ring, which consists mainly of water ice grains, smaller than a few micrometres, referred to as dust. LÄS MER

5. 4. Atomic Spectroscopy on Fusion Relevant Ions and Studies of Light Impurities in the JET Tokamak

   Författare :Magnus Tunklev; Partikel- och kärnfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Active and Passive Charge Exchange; Transport; Diffusion; Convection; Neutral Background Densities; Ion temperatures; Fusion; Isoelectronic sequences; Plasma; Atom- och molekylärfysik; Fysicumarkivet A:1999:Tunklev; Ritz formalism; Plume; Atomic and molecular physics;

   Sammanfattning : The spectrum and energy levels C IV and the 3l4l' system of the Mg-like ions in the iron group elements has been investigated. This has led to several hundred identified transitions, many of them previously unknown. LÄS MER

7. 5. Satellite observations of auroral acceleration processes

   Författare :Lars Eliasson; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Aurora; particle acceleration; space plasma; magnetosphere; ionosphere; polar cap; satellite observations;

   Sammanfattning : Measurements with satellite and sounding rocket borne instruments contain important information on remote and local processes in regions containing matter in the plasma state. The characteristic features of the particle distributions can be used to explain the morphology and dynamics of the different plasma populations. LÄS MER