Mastergradsoppgaver i teknologi - romfysikk: Recent submissions

Now showing items 41-49 of 49

    • Influence of Meteoric Aerosol particles on the Charge Balance in the Upper Mesosphere During ECOMA 2010 

      Svendsen, Åse (Master thesis; Mastergradsoppgave, 2011-12-15)
      This work is focused on the three sounding rocket launches during the ECOMA Geminids campaign in December 2010: One before the Geminids meteor shower, one at its peak and one some days after the peak. In this work, the main emphasis is on analyzing the results from electron and ion probes on the rockets, obtaining electron and ion density profiles, and comparing them with the measurements of meteoric ...

    • Air temperature at 90 km altitude in the Artic obtained using meteor radar : validation, characterization and climate change. 

      Kluken, Lars Grytbakk (Master thesis; Mastergradsoppgave, 2011-09-30)
      Temperatures at 90 km altitude above Ramfjordmoen (69°N, 19°E) have been obtained with the Nippon/Norwegian Tromsø Meteor Radar. The temperatures have been derived from meteor radar decay rates using two techniques: the pressure based and the temperature gradient based methods. The results have been compared to the Microwave Limb Sounder (MLS) instrument on board the Aura spacecraft. It was found ...

    • Na lidar measurements during the ECOMA/Geminids campaign with focus on Na peak density and temperature 

      Østerpart, Jørgen Olai Kristensen (Master thesis; Mastergradsoppgave, 2011-02)
      Using a resonance lidar, atomic Na (sodium) can be observed in the 80-110 km altitude range of the atmosphere. Na belongs to the alkali metal group and is highly reactive, so one could expect that it would quickly react with other particles and leave its atomic state. Its actual behaviour however includes the formation of relatively dense layers which, from the perspective of a stationary lidar, ...

    • Review and test of funnel shape geometries in solar wind acceleration 

      Trollebø, Robert (Master thesis; Mastergradsoppgave, 2009-12-15)
      The origin and heating of the solar wind is still a puzzle. We review in this study the idea that the solar wind originates in coronal funnels. We place emphasis on the fast solar wind. This study provides primarily a historic overview over the development of the idea of funnel expansion. We present examples of recent solar wind studies that investigate the funnel geometry. These studies include ...

    • Plasma line studies in relation to Naturally Enhanced Ion Acoustic Lines (NEIALs) 

      Knutsen, Joachim Sveia (Master thesis; Mastergradsoppgave, 2008-06-02)
      New to the ESR common programmes is the inclusion of plasma lines along with the standard ion power density spectrum. Using data from the IPY common programme, a programme that has been run all through the International Polar Year, we have gone through large amounts of analysed data trying to find periods in time that fulfils the known criteria for finding Naturally Enhanced Ion Acoustic Lines ...

    • Multifractals and their application to geospace data 

      Østvand, Lene (Master thesis; Mastergradsoppgave, 2008-06-02)
      In this thesis I first introduce multifractal theory and mathematical concepts for multifractal analysis. Different methods for different uses are described, with focus on a differentiating between coarse and fine theory approaches. Methods for analysing time series are also described, more specificly a direct method based on the coarse theory analysis, the wavelet transform modulus maxima ...

    • Characterization of a magnetized plasma in cylindrical geometry 

      Tribulato, Giulio (Master thesis; Mastergradsoppgave, 2007-06)
      Njord is a novel plasma device in which a low-temperature plasma is produced by RF waves inductively coupled into a cylindrical, magnetized vacuum. The main part of this project is to carry out an experimental characterization of the plasma in this device. The plasma expansion and acceleration of the source plasma into the main chamber will be of specific interest. The ultimate aim will then be to ...

    • Spectral observations of Polar Mesospheric Summer Echoes (PMSE) 

      López Muñoz, Aquilino (Master thesis; Mastergradsoppgave, 2007-06-15)
      We present spectral measurements of PMSE under the influence of HF heating cycles. The data has been obtained with EISCAT VHF radar, during the EISCAT campaign 2004 in Tromsø. Examples where the PMSE overshoot appears when the electrons are heated with a specific cycle are shown. A detailed analysis of PMSE spectral width during the heating cycles concluded that there is no evidence of a possible ...

    • A theoretical study of the coupling between minor ions and protons in the solar transition region 

      Byhring, Hanne Sigrun (Master thesis; Mastergradsoppgave, 2007-06-01)
      We have used a numerical model to calculate the flow velocities of six minor ion species, using two different background models for the fast solar wind, one with a slow expansion, and one with a very rapidly expanding geometry. By comparing the flow velocity of the minor ions and the protons, we have investigated the degree of coupling between minor ions and the background solar wind in the solar ...