| Title: |
Modeling Jupiter's Dawnside Magnetodisc: Using Juno Observations to Constrain a Radial Force‐Balance Model. |
| Authors: |
Provan, G.1 (AUTHOR) gp31@leicester.ac.uk; Nichols, J. D.1 (AUTHOR); Cowley, S. W. H.1 (AUTHOR); Bagenal, F.2 (AUTHOR); Wilson, R. J.2 (AUTHOR) |
| Source: |
Journal of Geophysical Research. Space Physics. Apr2025, Vol. 130 Issue 4, p1-22. 22p. |
| Subject Terms: |
Magnetic field measurements; Plasma currents; High temperature plasmas; Low temperature plasmas; Current distribution |
| Abstract: |
This study investigates Jupiter's dawnside magnetodisc, using plasma and magnetic field measurements from Juno orbits 5 to 12 to refine a radial force‐balance magnetodisc model. This iterative vector potential model examines variations in the azimuthal magnetodisc current, coupled with a magnetosphere‐ionosphere coupling model from which the radial current is simultaneously obtained. Three key force‐balance parameters are used: the hot plasma parameter (pV, Pa m T−1), the mass outflow rate of cold iogenic plasma, and the height‐integrated ionospheric Pedersen conductivity. Axisymmetric equilibrium outputs are compared to Juno's residual magnetic field and heavy ion density data between 15 and 60 RJ. Optimal parameter values for each orbit and overall current distributions are determined. Averaged modeled values are (1.63 ± 0.17) × 107 Pa m T−1 for the hot plasma parameter, 1,340 ± 350 kg s−1 for the mass outflow rate, and 0.26 ± 0.08 mho for the Pedersen conductivity. The overall modeled magnetodisc azimuthal current to 60 RJ is 266 ± 23 MA, varying similarly to the currents determined by Connerney et al. (2020, https://doi.org/10.1029/2020JA028138) but typically ∼50 MA larger. Of this total, the hot plasma current 158 ± 13 MA is larger than the cold plasma current 109 ± 23 MA, and dominates in the inner region. The cold plasma current typically becomes the larger component beyond ∼35 RJ and exhibits greater orbit‐to‐orbit variability. The mass outflow rate from Io is the primary driver of magnetodisc current variability. The north‐south summed radial magnetosphere‐ionosphere coupling current 104 ± 31 MA is typically ∼40% of the total azimuthal current, with variations that are only weakly correlated. Key Points: We employ magnetic field and ion data on Juno orbits 5–12 to determine magnetodisc and M‐I coupling currents using the Nichols (2011, https://doi.org/10.1029/2011JA016922) modelThe hot plasma current 158 ± 13 MA (to 60 RJ) is the larger in the magnetodisc though the cold plasma current 109 ± 23 MA is the more variableThe north‐south summed M‐I coupling current 104 ± 31 MA is ∼40% of the magnetodisc current 266 ± 23 MA but variations are only weakly correlated [ABSTRACT FROM AUTHOR] |
| : |
Copyright of Journal of Geophysical Research. Space Physics is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) |
| Database: |
GreenFILE |