Sökning: "Rymdfysik"

Visar resultat 16 - 20 av 240 avhandlingar innehållade ordet Rymdfysik.

  1. 16. 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

  3. 17. Waves in space plasmas : Lower hybrid cavities and simple-pole distribution functions

    Författare :Anders Tjulin; Mats André; Hans Pécseli; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; space physics; plasma; waves; dispersion relations; lower hybrid cavities; Cluster; magnetosphere; Rymd- och plasmafysik; Space physics; Rymdfysik;

    Sammanfattning : Waves are a fundamental feature in many parts of physics, since they transport energy without transporting matter. This is the case also in space physics. Waves are responsible for energy transport both between different parts of space and between different particles in the space plasma. LÄS MER

  4. 18. Calibration and quality assessment of DESCARTES : grabsampler for stratospheric tracers

    Författare :Johan Arvelius; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Adsorption; Balloon; Carboxen; CFC; Chloro-Fluoro Carbon; Grab sampling; Halocarbon; Molecular sieve; Stratospheric tracer; Tracer; Adsorption; Ballong; Carboxen; CFC; Halogeniserade kolväten; Klor-Flourkarbon; Spårgas; Stratosfärisk spårgas; Space physics; Rymdfysik;

    Sammanfattning : DESCARTES is a light-weight, balloon-borne grab sampler for stratospheric long-lived tracers developed at the University of Cambridge. 33 flights have been performed with two versions of the instrument at northern latitudes by the DESCARTES team at the Swedish Institute of Space Physics (IRF) in Kiruna during the years 1997-2000. LÄS MER

  5. 19. Energization and Acceleration of Dayside Polar Outflowing Oxygen

    Författare :Sachiko Arvelius; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Solar wind-magnetosphere interactions; Magnetosphere-ionosphere coupling; O energization acceleration; O outflow; Space physics; Rymdfysik;

    Sammanfattning : This thesis deals with energetic oxygen ions (i.e. single-charged atomic oxygen ions, O+) at altitudes higher than 5 Earth radii (RE) and at latitudes above 75 (toward 90) degrees invariant latitude (deg ILAT) in the dayside polar magnetosphere observed by Cluster. LÄS MER

  7. 20. Instrumentation for energetic Neutral atom measurements at Mars, Venus and The Earth

    Författare :Klas Brinkfeldt; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Energetic neutral atoms; instruments and techniques; mass spectrometry; microchannel plates; solid state detectors; solar wind interaction; planets; magnetosphere; exosphere; ring current; Space physics; Rymdfysik;

    Sammanfattning : This thesis deals with the development and calibrations of sensors to measure energetic neutral atoms (ENAs) at Mars, Venus, and the Earth. ENAs are formed in charge exchange processes between energetic, singly--charged ions and a cold neutral gas. LÄS MER