Ebert RW, Greathouse TK, Clark G, Allegrini F, Bagenal F, Bolton SJ, Connerney JEP, Gladstone GR, Imai M, Hue V, Kurth WS, Levin S, Louarn P, Mauk BH, McComas DJ, Paranicas C, Szalay JR, Thomsen MF, Valek PW, Wilson RJ. Comparing Electron Energetics and UV Brightness in Jupiter's Northern Polar Region During Juno Perijove 5.
GEOPHYSICAL RESEARCH LETTERS 2019;
46:19-27. [PMID:
30828110 PMCID:
PMC6378591 DOI:
10.1029/2018gl081129]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/14/2018] [Accepted: 12/20/2018] [Indexed: 05/24/2023]
Abstract
We compare electron and UV observations mapping to the same location in Jupiter's northern polar region, poleward of the main aurora, during Juno perijove 5. Simultaneous peaks in UV brightness and electron energy flux are identified when observations map to the same location at the same time. The downward energy flux during these simultaneous observations was not sufficient to generate the observed UV brightness; the upward energy flux was. We propose that the primary acceleration region is below Juno's altitude, from which the more intense upward electrons originate. For the complete interval, the UV brightness peaked at ~240 kilorayleigh (kR); the downward and upward energy fluxes peaked at 60 and 700 mW/m2, respectively. Increased downward energy fluxes are associated with increased contributions from tens of keV electrons. These observations provide evidence that bidirectional electron beams with broad energy distributions can produce tens to hundreds of kilorayleigh polar UV emissions.
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