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Closed Fluxtubes and Dispersive Proton Conics at Jupiter's Polar Cap
J R Szalay1, G Clark2, G Livadiotis1
1Department of Astrophysical Sciences Princeton University Princeton NJ USA.
Geophysical Research Letters
|July 21, 2022
Summary
Jupiter
Area of Science:
- Planetary Science
- Plasma Physics
- Magnetospheric Physics
Background:
- Jupiter's magnetosphere hosts complex energetic particle populations.
- Understanding particle acceleration mechanisms is key to magnetospheric dynamics.
Purpose of the Study:
- Investigate the origin and acceleration of energetic protons over Jupiter's southern polar cap.
- Determine the role of wave-particle interactions in proton energization.
Main Methods:
- Analysis of in-situ spacecraft observations of proton populations.
- Correlation of particle data with plasma wave characteristics.
Main Results:
- Identified two distinct proton populations: a core population (~1 keV) and a dispersive conic population (~1-300 keV).
- The core protons likely seed the higher-energy conics, accelerated via transient wave-particle heating.
- Evidence for topologically closed field lines connecting conjugate hemispheres over the polar cap.
Conclusions:
- Proton acceleration occurs via a "pressure-cooker" process in Jupiter's inner magnetosphere.
- Energetic protons can be transported into Jupiter's magnetotail through wave-particle coupling.
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