Sökning: "plasma analysis"

Visar resultat 16 - 20 av 900 avhandlingar innehållade orden plasma analysis.

1. 16. Waves and instabilities in quantum plasmas

   Författare :Shahid Ali; Padma Kant Shukla; Mattias Marklund; Jose Tito Mendonca; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Quantum mechanical effects; dusty plasma; linear and nonlinear waves; instabilities; nonlinear wave interactions; density gradients; magnetoplasmas.; Plasma physics; Plasmafysik;

   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

3. 17. High-speed jets and related phenomena at Earth's bow shock and magnetosheath

   Författare :Savvas Raptis; Tomas Karlsson; Drew Turner; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; magnetosheath; solar wind; bow shock; plasma; collisionless shock; Physics; Fysik;

   Sammanfattning : Magnetosheath high-speed jets are transient and localized dynamic pressure enhancements downstream of Earth’s bow shock. Their formation has been associated with several mechanisms, including solar transient events and the dynamical evolution of the bow shock. LÄS MER

4. 18. Making TOFu : Fusion Plasma Neutron Emission Spectrometry with a Fully Digital Data Acquisition System

   Författare :Mateusz Skiba; Göran Ericsson; Anders Hjalmarsson; Carl Hellesen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fusion; plasma diagnostics; neutron spectrometry; TOFOR; tokamak; JET; digital data acquisition; Fysik med inriktning mot tillämpad kärnfysik; Physics with specialization in Applied Nuclear Physics;

   Sammanfattning : TOFu (Time-Of-Flight upgrade) is a fully digital data acquisition system based on 1 GSPS, 12 bit digitisers for the TOFOR (Time-Of-Flight spectrometer Optimised for Rate) fusion neutron spectrometer at JET. The system has been assessed, developed and subsequently tested during experimental campaigns at JET. LÄS MER

5. 19. Nonaxisymmetric experimental modal analysis and control of resistive wall MHD in RFPs : System identification and feedback control for the reversed-field pinch

   Författare :K Erik J Olofsson; Per Brunsell; Marco Ariola; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magnetic confinement fusion; Reversed-field pinch; System identification; Magnetohydrodynamics; Modal analysis; Automatic control; Resistive wall modes;

   Sammanfattning : The reversed-field pinch (RFP) is a device for magnetic confinement of fusion plasmas. The main objective of fusion plasma research is to realise cost-effective thermonuclear fusion power plants. The RFP is highly unstable as can be explained by the theory of magnetohydrodynamics (MHD). LÄS MER

7. 20. Multi-sightline neutron emission spectroscopy of D and T fusion plasmas at JET

   Författare :Arne Sahlberg; Jacob Eriksson; Sean Conroy; Göran Ericsson; Manuel Garcia-Muñoz; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fusion; tokamak; neutron spectroscopy; fusion plasma diagnostics; data analysis; fast ion distribution; Fysik; Physics;

   Sammanfattning : An analysis of the neutron emission from a fusion plasma can be used to determine plasma properties and diagnose fusion performance. In this thesis, several analysis methods for neutron spectroscopy are presented and applied to data from the experimental fusion device JET. LÄS MER