Search for dissertations about: "electron waves"

Showing result 1 - 5 of 70 swedish dissertations containing the words electron waves.

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

    Author : Elias Odelstad; Anders Eriksson; Andrew Coates; Uppsala universitet; []
    Keywords : 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;

    Abstract : 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. READ MORE

  2. 2. Electron energization in near-Earth space : Studies of kinetic scales using multi-spacecraft data

    Author : Elin Eriksson; Andris Vaivads; Masahiro Hoshino; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; magnetic reconnection; electron acceleration; electron heating; magnetosheath; magnetotail; magnetic nulls; Cluster; Magnetospheric MultiScale; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

    Abstract : Plasma, a gas of charged particles exhibiting collective behavior, is everywhere in the Universe. The heating of plasma to millions of degrees and acceleration of charged particles to very high energies has been observed in many astrophysical environments. How and where the heating and acceleration occur is in many cases unclear. READ MORE

  3. 3. Studies of acoustic waves, noise and charge pumping using single-electron devices

    Author : Martin Gustafsson; Chalmers University of Technology; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; single-electron pump; single-electron transistor; surface acoustic wave; single-electron devices; charge pumping; TLF; SINIS turnstile; electrometer; two-level fluctuator; single-photon detector; noise; SAW; SET;

    Abstract : This thesis covers a range of experiments on single-electron devices, electrical circuits that utilize the discreetness of the electron charge. The Single-Electron Transistor (SET) is of special importance among these, being the most sensitive electrometer demonstrated, and sufficiently mature to serve as a building block in sensors and detectors for physical phenomena that can be transformed into charge signals. READ MORE

  4. 4. VLF and ULF Waves Associated with Magnetospheric Substorms

    Author : Andrew Collier; Lars Blomberg; James McKenzie; KTH; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Space physics; Subtorms; Magnetosphere; VLF waves; ULF waves; Space physics; Rymdfysik;

    Abstract : A magnetospheric substorm is manifested in a variety of phenomena observed both in space and on the ground. Two electromagnetic signatures are the Substorm Chorus Event (SCE) and Pi2 pulsations. The SCE is a Very Low Frequency (VLF) radio phenomenon observed on the ground after the onset of the substorm expansion phase. READ MORE

  5. 5. The importance of waves in space plasmas : Examples from the auroral region and the magnetopause

    Author : Gabriella Stenberg; Umeå universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; Plasma waves; magnetospheric physics; magnetopause; auroral region; wave distribution function; space exploration; reconnection; current tubes; Rymd- och plasmafysik; Space physics; Rymdfysik; rymdfysik; Space Physics;

    Abstract : This thesis discusses the reasons for space exploration and space science. Space plasma physics is identified as an essential building block to understand the space environment and it is argued that observation and analysis of space plasma waves is an important approach.Space plasma waves are the main actors in many important processes. READ MORE