Multi-Year Observations of Ultra-Relativistic Electrons with the Van Allen Probes Mission
Multi-Year Observations of Ultra-Relativistic Electrons with the Van Allen Probes Mission
Monday, 5 March 2018: 08:30
Longshot and Bogey (Hotel Quinta da Marinha)
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Abstract:
From the launch in August 2012 to the present time, the Van Allen Probes mission has made nearly continuous measurements of the highly- and ultra-relativistic electron populations in Earth’s radiation belts. In this presentation we focus on 1-20 MeV electron measurements made by the twin Relativistic Electron-Proton Telescope (REPT) instruments that were first turned on in early September 2012. We describe the morphological features seen repeatedly in the data (3-belt structures, “impenetrable” barrier properties, radial diffusion signatures) in the context of acceleration and loss mechanisms. We especially focus on solar wind forcing of the ultra-relativistic (E ≳ 5 MeV) electron populations. We present pitch angle resolved data and energy-spectral analyses for key events. The presentation also includes animated segments portraying the mission-long time variability of the outer Van Allen belt emphasizing the remarkable dynamics of the system.