Search for dissertations about: "ion velocities"

Showing result 1 - 5 of 28 swedish dissertations containing the words ion velocities.

  1. 1. A study of the structure and dynamics of Saturn's inner plasma disk

    Author : Mika Holmberg; Jan-Erik Wahlund; Nikolai Piskunov; Svetlana Ratynskaia; Thomas Cravens; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Planetary magnetospheres; Saturn; magnetospheric dynamics; Saturn s inner plasma disk; ring plasma; ion densities; ion velocities; dayside nightside asymmetry; ion loss rates; Cassini; Langmuir probe; RPWS; Space Physics; Rymdfysik;

    Abstract : This thesis presents a study of the inner plasma disk of Saturn. The results are derived from measurements by the instruments on board the Cassini spacecraft, mainly the Cassini Langmuir probe (LP), which has been in orbit around Saturn since 2004. READ MORE

  2. 2. 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

  3. 3. Final-State-Resolved Mutual Neutralization of Li+ and H-

    Author : Alice F. Schmidt-May; Henning T. Schmidt; Fivos Perakis; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; DESIREE; ion; mutual neutralization; collision; lithium; hydrogen; Physics; fysik;

    Abstract : We studied the mutual neutralization of Li+ and H- at effective collision energies of a few hundred meV, which corresponds to temperatures of around 2000 K, in the double ion storage ring DESIREE.We present a new approach to match beam velocities and a new general analysis method for non-fragmenting mutual neutralization at DESIREE. READ MORE

  4. 4. Electron-transfer processes in fast ion-atom collisions

    Author : Kristian Støchkel; Henning Schmidt; Henrik Cederquist; Andreas Wolf; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electron transfer processes fast ion atom collisions hydrogen helium; Atomic and molecular physics; Atom- och molekylfysik;

    Abstract : The subject of this thesis is experimental studies of electron-transfer processes in ion-atom collisions at velocities significantly higher than typical orbital velocities of electrons in bound states of atoms or molecules. The experimental technique applied combines the high beam intensity of heavy-ion storage rings with a supersonic gas-jet target equipped with a recoil-ion-momentum spectrometer. READ MORE

  5. 5. Solitary waves and enhanced incoherent scatter ion lines

    Author : Jonas Ekeberg; Lars Eliasson; Kristof Stasiewicz; Jan Trulsen; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; plasma waves and instabilities; nonlinear phenomena; solitons and solitary waves; ionosphere; Sun: corona; incoherent scatter radar; MHD; plasmavågor och instabiliteter; ickelinjära fenomen; solitoner och solitära vågor; jonosfär; solen: korona; inkoherent spridningsradar; MHD; Geocosmophysics and plasma physics; Geokosmofysik och plasmafysik; Space physics; Rymdfysik; Plasma physics; Plasmafysik; Non-linear dynamics; chaos; Icke-linjär dynamik; kaos; fysik; Physics; rymd- och plasmafysik; Space and Plasma Physics;

    Abstract : This thesis addresses solitary waves and their significance for auroral particle acceleration, coronal heating and incoherent scatter radar spectra. Solitary waves are formed due to a balance of nonlinear and dispersive effects. READ MORE