Multi-wavelength Observations of South Atlantic Anomaly Region

Abstract:

The South Atlantic Anomaly (SAA) is a region where the Earth’s magnetic field is at its weakest. The energetic particles captured by the geomagnetic field can come closest to the Earth's surface forming a high-radiation region. The ISUAL (Imager of Sprites and Upper Atmospheric Lightning) is a scientific payload aboard the FORMOSAT-2 satellite. The scientific payload consists of an intensifier CCD Imager, an array photometer, and a six-channel spectrophotometers. ISUAL had been monitoring airglow and aurora in the global ionosphere. In this study, we will use ISUAL images and photometer data to analyze the background emissions in the SAA region. From the emission production mechanisms for different measurement channels, we can estimate the properties of the plasma precipitating from the inner radiation belt into the ionosphere of the SAA region. Besides, the ratios of different emissions are also discussed.