Space Plasma Seminar: Ultra-Relativistic Electrons in the Van Allen Radiation Belts

Dr. Yuri Y. Shprits, Research Geophysicist, Institute of Geophysics and Planetary Physics, Department of Earth and Space Sciences, Department of Atmospheric and Oceanic Sciences, UCLA

Tuesday, April 8, 2014, 3:30-5:00pm

Wilder 111

The Van Allen radiation belts consist of energetic electrons and ions at energies above 100 keV trapped by the Earth's magnetic field. These very energetic particles may be harmful to satellite electronics and humans in space. Observations together with predictive and data assimilative modeling showed that energetic electrons can be accelerated to relativistic energies by taking energy from ULF and VLF plasma waves during resonant wave-particles interactions. Recent observations by NASA's Van Allen Probes showed an event where three radiation zones were observed at ultra-relativistic energies. The additional middle, and unusually narrow, belt persisted for approximately 4 weeks. Detailed observations from the Van Allen Probes mission and Versatile Electron Radiation Belt (VERB) code modeling demonstrate that different physical processes can dominate acceleration and loss of particles at ultra-relativistic energies, which explains the unusual spacial and temporal structures in the radiation belts.

For more information, contact Tressena Manning at 603-646-2854 or tressena.a.manning@dartmouth.edu.