Student: Sadie Elliott, Graduate Student in Physics and Astronomy, University of Iowa
Faculty Advisor: Donald Gurnett
The acceleration of up-going electrons in the Jovian polar cap via whistler-mode wave-particle interactions: Observations from the Juno spacecraft
I work on data analysis from NASA’s Juno mission to Jupiter under the supervision of both Dr. Donald Gurnett (academic advisor) and Dr. William Kurth. I conduct research on the interactions occurring between electrons and plasma waves in the Jovian polar regions. In particular, I look at how whistler-mode waves can accelerate electrons to relativistic energies. Recently, the Juno spacecraft discovered upward-traveling energetic electrons (from tens of keV to several MeV) over the Jovian polar cap [Mauk et al., GRL 2017]. The electrons were found to have nearly power law energy distributions, indicative of a stochastic acceleration process. Intense upward-propagating broadband whistler-mode waves were also observed over the entire Jovian polar cap [Tetrick et al., GRL 2017] and were found to pitch angle scatter the electrons [Elliott et al., GRL 2018]. My research focuses on understanding how electrons can be accelerated by whistler-mode waves via wave-particle interactions. This study is vital to our overall understanding of auroral processes at Jupiter. Because the aurora is created by energetic particles bombarding the atmosphere (at Earth, Jupiter, or other planets), explaining how particles are accelerated is key to understanding the underlying physics of this beautiful phenomenon. We study the aurora at Jupiter because it provides a different environment for applying and testing existing theories. If terrestrial theories don’t work at Jupiter, the physics must be altered. Furthering our knowledge of how the aurora works at Jupiter can also improve our understanding of other similar gas giants.