Energetic particle injection events in the Kronian magnetosphere

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The Kronian magnetosphere is highly dynamic, particularly in the region between 3 Rs and 13 Rs, where numerous hot plasma injections occur with energies reaching a few hundred keV. This thesis focuses on electron measurements from the Magnetospheric Imaging Instrument (MIMI) aboard the Cassini spacecraft, examining the properties of these events to better understand the global configuration of the magnetosphere. Findings indicate that magnetospheric plasma subcorotates at approximately 80% of full corotation between 8 Rs and 13 Rs, and inverted electron dispersion profiles are explained through a differential velocity profile. The night and morning sectors are identified as the primary regions for hot plasma injection generation, with event intensity showing a clear local time dependency. Injections from the noon to midnight sector are less intense than those from midnight to noon, providing insights into the underlying mechanisms. Low-intensity injections are linked to interchange instability, while high-intensity ones may result from dipolarization due to magnetic reconnection in Saturn's magnetotail. The analysis suggests that these injections have a lifetime of about two planetary rotations within the studied energy range.