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Visar resultat 1 - 5 av 8 avhandlingar som matchar ovanstående sökkriterier.

1. 1. 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

3. 2. Solar Wind Proton Interactions with Lunar Magnetic Anomalies and Regolith

   Författare :Charles Lue; Yoshifumi Futaana; Stas Barabash; Urs Mall; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; the Moon; solar wind; magnetic anomalies; regolith; space physics; plasma physics; particle-surface interactions; mini-magnetospheres; energetic neutral atoms; Space Physics; rymdfysik;

   Sammanfattning : The lunar space environment is shaped by the interaction between the Moon and the solar wind. In the present thesis, we investigate two aspects of this interaction, namely the interaction between solar wind protons and lunar crustal magnetic anomalies, and the interaction between solar wind protons and lunar regolith. LÄS MER

4. 3. The Neutral Particle Detector on the Mars and Venus Express missions

   Författare :Alexander Grigoriev; Stas Barabash; Brian J. Anderson; Umeå universitet; []
   Nyckelord :Space and plasma physics; ENA imaging; exosphere; magnetosphere; Mars; Venus; solar wind interaction; Rymd- och plasmafysik; rymd- och plasmafysik; Space and Plasma Physics;

   Sammanfattning : The Neutral Particle Detector (NPD) is a new type of instrumentation for energetic neutral atom (ENA) diagnostics. This thesis deals with development of the NPD sensor designed as a part of the plasma and neutral particle packages ASPERA-3 and ASPERA-4 on board Mars Express and Venus Express, the European Space Agency (ESA) satellites to Mars and Venus, respectively. LÄS MER

5. 4. Numerical modelling of ENAs from stellar wind interactions

   Författare :Andreas Ekenbäck; Mats Holmström; Michael R. Collier; Institutet för rymdfysik (IRF); []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Space physics; Space technology; Astrophysics; Space engineering; Rymdteknik;

   Sammanfattning : Energetic neutral atoms (ENAs) are produced whenever a stellar wind encounters a neutral atmosphere. If a stellar wind proton comes sufficiently close to a neutral a charge-exchange reaction may take place, transforming the proton into an ENA. LÄS MER

7. 5. Development of visible spectroscopic techniques for applications in plasma diagnostics

   Författare :Katarzyna Jakubowska; Elisabeth Rachlew-Källne; Per Brusell; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

   Sammanfattning : In this thesis visible spectroscopy is developed and used for two applications. Studies of motional Stark effect spectra for diagnosing the current distribution in the fusion plasmas with two different spectroscopic diagnostic systems: ratiometry and interferometry. LÄS MER