DAYTIME MEASUREMENTS OF OPTICAL AURORAL EMISSIONS FROM ANTARCTICA

Optical methods have enabled us to detect auroral emissions during daytime conditions, and to identify a narrow latitudinal region of energetic particle precipitation from the Indian station Maitri (11-degrees-38'E; 70-degrees-45'S; 62.8-degrees-S I-lat.) in Antarctica. These observations are new. The energetic particles originate within the closed geomagnetic field lines close to the plasmapause region and maximize approximately 0830 h MLT (Magnetic Local Time) (approximately 1200 UT). Enhanced proton precipitation activity could also be inferred during a moderate geomagnetic storm, suggesting the enhancement/activation of acceleration mechanisms during this event.