Thesis for Doctor Scientiarum (Ph.D)

My thesis for the Dr. Scient. degree was devoted to the study of X-ray data from the PIXIE (Polar Ionospheric X-ray Imaging Experiment) camera on board the POLAR satellite. This camera has provided the first true two dimensional pictures of the global X-ray aurora. The focus of the thesis has been to evaluate the remote sensing technique of X rays and especially to extract spectral information about the parent electron precipitation

The monograph and the papers that constitutes the thesis are all available as pdf documents (below)

The Thesis

• Frontpage
• Errata
• Preface, Contents etc
• The dynamics of energetic electron precipitation during substorms - Utilization of the remote sensing technique of X rays The monograph for my thesis , submitted , September 1999.

Published papers in the thesis

• Paper 1. Simultaneous Measurements of X-rays and Electrons During a Pulsating Aurora Ann. Geophysicae, 16, 148 - 160, 1998

• Paper 2. Global Scale Electron Precipitation Features seen in UV and X-rays During Substorms , J. Geophys. Res. , 104, 10,191 - 10,204, 1999.
  Fourteen substorms are examined in PIXIE and UVI onboard Polar. LANL, WIND and groundbased data are examined for each event. The different phases of the substorm are studied. The time development in every two hour local time sector are shown and we focus on the intensified precipitation seen in the morning sector delayed relative to onset, which is seen in all the fourteen substorm events. Drift time calculations show that the intensification is most probably caused by the electrons injected in the midnight sector, drifting into the morning sector where some mechanism scatter the electrons into the loss cone.

• Paper 3. Magnetospheric and Ionospheric Response to a Substorm: GEOTAIL HEP-LD and POLAR PIXIE Observations, J. Geophys. Res. Vol. 104, No. A12, p. 28,459. 1999.
  Two substorm onsets are observed 10 December 1996 by GEOTAIL (in the far midnight tail region), as reconnection and ion flow events and by PIXIE as X-ray emissions from the ionosphere. Additional data from WIND,LANL and ground based magnetic measurements are studied. Using the Tsyganenko model of 1996, the contours of X-ray emissions are mapped into the equtorial plane, indicating the localion of the source region for the precipitation. The dataset is interpreted and a possible scenario for the two substorm onsets are presented.

• Paper 4. Global X-ray emission during an isolated substorm - A case study , Special issue of J. Atmos. Solar-Terr. Phys., Vol. 62 (10), p. 889 - 900, 2000.
  An isolated substorm uccurring September 4, 1997 is studied. PIXIE and UVI images, Geotail particle measurements in the tail and NOAA-12 and DMSP low altitude satellite data are used to study the substorm. Measured and calculated X-ray profiles in the morning sector are presented

• Paper 5. Localized maximum of X-ray emission in the morning sector caused by drifting electrons ,J. Geophys. Res., Vol. 105, No A9, p. 20,869 - 20,885, 2000

Technical Report in the thesis

• Technical Report. PIXIE data processing at the University of Bergen, Scientific Technical Repport, 1999-05, ISSN-0803-266.
  A detailed description on how images and energy spectra are processed from the PIXIE data.

Unrefereed Papers, Posters and Talks, i.e., prestudies for the papers listed above

• Global Scale Electron Precipitation Features During Substorms,Poster at the AGU fall meeting 1997 (awarded as an Outstanding Student Paper)

• Global Scale Electron Precipitation During Substorm Expansions, Proceedings of the International Conference on Substorms -4, 1998, Terra Scientific Publishing Company, Tokyo, Y.Kamide, editor

• Magnetospheric and Ionospheric Response to a Substorm: GEOTAIL HEP-LD and POLAR PIXIE Observations, Poster at the AGU spring meeting 1998

• Intensified Energetic Electron Precipitation in the Morning Sector Caused by Drift ing Electrons, Invited talk at the Sixth Huntsville Modeling Workshop, Guntersville, Alabama, 26-30 October 1998

• Localized maximum of X-ray emission in the morning sector caused by drifting electrons, Talk at AGU spring meeting, June 1-4,1999, Boston