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Visar resultat 6 - 10 av 19 avhandlingar som matchar ovanstående sökkriterier.

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

   Författare :Elin Eriksson; Andris Vaivads; Masahiro Hoshino; Uppsala universitet; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

3. 7. Low-energy ions around comet 67P/Churyumov-Gerasimenko

   Författare :Sofia Bergman; Gabriella Stenberg Wieser; Martin Wieser; Gert Brodin; Stein Håland; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Low-energy ions; spacecraft charging; comets; 67P Churyumov-Gerasimenko; Rosetta; RPC-ICA; SPIS; diamagnetic cavity; field of view; plasma; space plasma physics; rymd- och plasmafysik; Space and Plasma Physics;

   Sammanfattning : Low-energy ions play important roles in the formation of the plasma environment around a comet. Reliable ways of measuring these ions are therefore of high importance to fully understand the processes and dynamics of this environment. Unfortunately, low-energy ions are infamously difficult to detect. LÄS MER

4. 8. Integrated Communications and Thermal Management Systems for Microsystem-based Spacecraft : A Multifunctional Microsystem Approach

   Författare :Henrik Kratz; Anders Rydberg; Johan Köhler; Pelle Rangsten; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronics; nanospacecraft; MST; MEMS; silicon; communication; thermal management; antenna; paraffin; PCM; multifunctional; microsystems; Elektronik; Electronics; Elektronik;

   Sammanfattning : This thesis explores the potential of multifunctional silicon-based microsystems for advanced integrated nanospacecraft (AIN). Especially, multifunctional microsystems with the coexistant functions of communications and thermal management implemented in multilayer silicon stacks are approached with systems study. LÄS MER

5. 9. Low-Energy Ion Escape from the Terrestrial Polar Regions

   Författare :Erik Engwall; Anders I. Eriksson; Mats André; Thomas Moore; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; space physics; ion outflow; polar wind; auroral upflows; atmospheric escape; magnetotail lobes; spacecraft wake; electric field measurements; Geocosmophysics and plasma physics; Geokosmofysik och plasmafysik; Space and Plasma Physics; rymd- och plasmafysik;

   Sammanfattning : The contemporary terrestrial atmosphere loses matter at a rate of around 100,000 tons per year. A major fraction of the net mass loss is constituted by ions, mainly H+ and O+, which escape from the Earth’s ionosphere in the polar regions. LÄS MER

7. 10. Rosetta Observations of Plasma and Dust at Comet 67P

   Författare :Fredrik Leffe Johansson; Anders Eriksson; Jan-Erik Wahlund; Nicolas André; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Rosetta; Comets; Plasma; Langmuir Probes; Dust; Spacecraft-plasma interaction; Electrostatic Probes; Rosetta; kometer; plasma; stoft; rymdfarkost-plasma växelverkan; Fysik med inriktning mot rymd- och plasmafysik; Physics with specialization in Space and Plasma Physics;

   Sammanfattning : In-situ observations of cometary plasma are not made because they are easy. The historic ESA Rosetta mission was launched in 2004 and traversed space for ten years before arriving at comet 67P/Churyumov-Gerasimenko, which it studied in unprecedented detail for two years. LÄS MER