Sökning: "plasma instability"
Visar resultat 6 - 10 av 68 avhandlingar innehållade orden plasma instability.
6. Modelling of laser plasma interaction with applications to particle acceleration and radiation generation
Sammanfattning : The development of laser systems with ultra-high intensities has allowed the study of the relativistic interaction of laser light and ionized matter, plasmas, as well as opened up prospects for compact particle accelerators, generation of high intensity X-ray, XUV radiation, and probing QED-effects, which are present in the high intensity regime. To describe laser matter interaction, it is necessary to self-consistently account for the paths of a large number of particles and the corresponding electromagnetic fields, with the addition of stochastic effects at high laser intensities. LÄS MER
7. Electrostatic plasma waves associated with collisionless magnetic reconnection : Spacecraft observations
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
8. Fronts and instabilities in laser ablation, organic semiconductors and quantum media
Sammanfattning : The concept of a front plays a decisive role in various elds in physics and beyond. In the present thesis we study key aspects of front dynamics and stability in the context of laser plasmas, organic semiconductors and quantum media. LÄS MER
9. 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
10. Resonant magnetic perturbation effect on the tearing mode dynamics : Novel measurements and modeling of magnetic fluctuation induced momentum transport in the reversed-field pinch
Sammanfattning : The tearing mode (TM) is a resistive instability that can arise in magnetically confined plasmas. The TM can be driven unstable by the gradient of the plasma current. When the mode grows it destroys the magnetic field symmetry and reconnects the magnetic field in the form of a so-called magnetic island. LÄS MER