Sökning: "Electron plasma waves"

Visar resultat 1 - 5 av 41 avhandlingar innehållade orden Electron plasma waves.

  1. 1. Space Plasma Dynamics : Instabilities, Coherent Vortices and Covariant Parametrization

    Författare :David Sundkvist; Jan-Erik Wahlund; Andris Vaivads; Stuart Bale; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; space physics; plasma; instabilities; turbulence; coherent structures; vortex; self-organization; magnetosphere; waves; electromagnetism; covariant; space instrumentation; Rymd- och plasmafysik; Space physics; Rymdfysik;

    Sammanfattning : The magnetospheric cusps are two funnel-like regions of Earth's magnetosphere where solar wind plasma can have direct access to the ionosphere. The cusps are very dynamic regions where wave-particle interactions continuously take place and redistribute energy among different particle populations. LÄS MER

  2. 2. Plasma environment of an intermediately active comet : Evolution and dynamics observed by ESA's Rosetta spacecraft at 67P/Churyumov-Gerasimenko

    Författare :Elias Odelstad; Anders Eriksson; Andrew Coates; Uppsala universitet; []
    Nyckelord :Rosetta; comet; 67P; RPC-LAP; RPC-MIP; RPC-ICA; RPC-MAG; ROSINA-COPS; Langmuir probe; spacecraft potential; plasma; Churyumov-Gerasimenko; ion composition analyzer; diamagnetic cavity; ion velocity; electron temperature; ion-neutral drag; collisional coupling; wake effects; filamentation; electron cooling; plasma waves; hybrid waves; Bernstein waves; minimum variance; polarization; wavelet; density fluctuations; magnetic field oscillations; drift-cyclotron instability; asymmetric plasma and magnetic field enhancements; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

    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

  3. 3. Drift-Type Waves in Rotating Tokamak Plasma

    Författare :Elina Asp; Vladimir Pavlenko; Hans Nordman; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; fusion; plasma; tokamak; rotation; drift; ship; ITG; TE; Landau; Te Ti; hot-electron; confinement; stiffness; Weiland; Rymd- och plasmafysik; Space physics; Rymdfysik; Space and Plasma Physics; rymd- och plasmafysik;

    Sammanfattning : The concept of energy production through the fusion of two light nuclei has been studied since the 1950’s. One of the major problems that fusion scientists have encountered is the confinement of the hot ionised gas, i.e. the plasma, in which the fusion process takes place. LÄS MER

  4. 4. Plasma properties in high power impulse magnetron sputtering

    Författare :Daniel Lundin; Ulf Helmersson; Jon Tomas Gudmundsson; Linköpings universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; HiPIMS; HPPMS; plasma; plasma transport; plasma instabilities; Plasma physics; Plasmafysik;

    Sammanfattning : The work presented in this thesis involves experimental and theoretical studies related to plasma properties in high power impulse magnetron sputtering (HiPIMS), and more specifically plasma transport. HiPIMS is an ionized PVD method based on conventional direct current magnetron sputtering (dcMS). LÄS MER

  5. 5. Electrostatic plasma waves associated with collisionless magnetic reconnection : Spacecraft observations

    Författare :Konrad Steinvall; Yuri Khotyaintsev; Daniel Graham; Andris Vaivads; Jonathan Rae; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Magnetic reconnection; Plasma waves; Electron holes; Solar wind; Magnetosphere; Magnetospheric Multiscale; Solar Orbiter; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

    Sammanfattning : Magnetic reconnection is a fundamental plasma process where changes in magnetic field topology result in explosive energy conversion, plasma mixing, heating, and energization. In geospace, magnetic reconnection couples the Earth’s magnetosphere to the solar wind plasma, enabling plasma transport across the magnetopause. LÄS MER