Sökning: "hybrid waves"
Visar resultat 1 - 5 av 34 avhandlingar innehållade orden hybrid waves.
1. Waves in space plasmas : Lower hybrid cavities and simple-pole distribution functions
Sammanfattning : Waves are a fundamental feature in many parts of physics, since they transport energy without transporting matter. This is the case also in space physics. Waves are responsible for energy transport both between different parts of space and between different particles in the space plasma. LÄS MER
2. Interaction between Electromagnetic Waves and Localized Plasma Oscillations
Sammanfattning : This thesis treats interaction between electromagnetic waves and localized plasma oscillations. Two specific physical systems are considered, namely artificially excited magnetic field-aligned irregularities (striations) and naturally excited lower hybrid solitary structures (LHSS). LÄS MER
3. Plasma environment of an intermediately active comet : Evolution and dynamics observed by ESA's Rosetta spacecraft at 67P/Churyumov-Gerasimenko
Sammanfattning : The subject of this thesis is the evolution and dynamics of the plasma environment of a moderately active comet before, during and after its closest approach to the Sun. For over 2 years in 2014-2016, the European Space Agency’s Rosetta spacecraft followed the comet 67P/Churyumov-Gerasimenko at distances typically between a few tens and a few hundred kilometers from the nucleus, the longest and closest inspection of a comet ever made. LÄS MER
4. Lower hybrid current drive in the Tore Supra tokamak
Sammanfattning : To control and extract energy from nuclear fusion reactions, a mixture of deuterium and tritium gases must be heated to temperatures on the order of 100 million degrees, whilst maintaining a sufficiently high density. The main difficulty is to confine the ionised gases, i.e. plasma, until the rate of fusion reactions becomes large enough. LÄS MER
5. Waves and instabilities in quantum plasmas
Sammanfattning : The study of waves and instabilities in quantum plasmas is of fundamental importance for understanding collective interactions in superdense astrophysical objects, in high intense laser-plasma/solid-matter interactions, in microelectronic devices and metallic nanostructures. In dense quantum plasmas, there are new pressure laws associated with the Fermi-Dirac distribution functions and new quantum forces associated with the quantum Bohm potential and the Bohr magnetization involving electron ½ spin. LÄS MER