Müller, Anna Liane (2011) Energetic particle injection events in the Kronian magnetosphere: applications and properties. PhD thesis, Universität zu Köln.
The Kronian magnetosphere is highly dynamical. The inner part between 3 Rs and 13 Rs contains numerous injections of hot plasma with energies up to a few hundred keV. This thesis concentrates on electron measurements of the Magnetospheric Imaging Instrument (MIMI) onboard the Cassini spacecraft. It describes properties of the events themselves and uses them as a tool to characterize aspects of the global configuration of the magnetosphere. We show that the magnetospheric plasma subcorotates with about 80 % of full corotation at radial distances between 8 Rs and 13 Rs and explain the observations of inverted electron dispersion profiles with a differential velocity profile. The night and the morning sector of the magnetosphere are the preferred regions for the generation of hot plasma injections. The intensities of injection events show a clear dependency on local time. Injections originating in the noon to midnight sector are less intense than the ones injected on the midnight to noon sector. These facts help to infer the mechanisms that causes the injections. The low intensity injections can be associated with the interchange instability while the high intensity injections might be generated through dipolarization due to magnetic reconnection in the magnetotail of Saturn. Considering the intensity of injections with respect to their age, we infer a lifetime of about two planetary rotations for injections in the analysed energy range.
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