Closed Fluxtubes and Proton Conics in Jupiter’s Polar Cap

<p class="Nominal">We present a discrete observation of diverse plasma populations and evidence of closed magnetic topology at Jupiter&#8217;s polar cap. Two distinct populations of protons are observed over Jupiter&#8217;s southern polar cap: a ~1 keV core population and ~1-300 keV dispersive conic population at 6-7 Jovian radii&#160;planetocentric distance. We find the 1 keV core protons are likely the seed population for the higher-energy dispersive conics. Transient wave-particle heating in a &#8220;pressure-cooker&#8221; process is likely responsible for this proton acceleration. The plasma characteristics and composition during this period show Jupiter's polar-most field lines can be topologically closed, with conjugate magnetic footpoints connected to both hemispheres. Finally, these observations demonstrate energetic protons can be accelerated into Jupiter's magnetotail via wave-particle coupling.</p>