TY - JOUR
T1 - Survey of Ion Properties in Jupiter's Plasma Sheet
T2 - Juno JADE-I Observations
AU - Kim, Thomas K.
AU - Ebert, R. W.
AU - Valek, P. W.
AU - Allegrini, F.
AU - McComas, D. J.
AU - Bagenal, F.
AU - Connerney, J. E.P.
AU - Livadiotis, G.
AU - Thomsen, M. F.
AU - Wilson, R. J.
AU - Bolton, S. J.
N1 - Funding Information:
This work is supported by National Aeronautics and Space Administration (NASA) Contract No. NNM06AA75C. The flight data used in this study are the L3 JADE and MAG data in NASA's Planetary Data System (PDS at https://pds.jpl.nasa.gov/), volumes JNO-J/SW-JAD-3-CALIBRATED-V1.0 (Version 02 files) and JNO-J-3-FGM-CAL-V1.0 (Version 01 files), respectively. The Juno spacecraft trajectory information was obtained from the Laboratory for Atmospheric and Space Physics website(https://lasp.colorado.edu/home/mop/missions/juno/trajectory-information/). George Livadiotis contributed under NNX17AB74G NASA's grant for plasma-magnetic field coupling.
Funding Information:
This work is supported by National Aeronautics and Space Administration (NASA) Contract No. NNM06AA75C. The flight data used in this study are the L3 JADE and MAG data in NASA's Planetary Data System (PDS at https://pds.jpl.nasa.gov/ ), volumes JNO‐J/SW‐JAD‐3‐CALIBRATED‐V1.0 (Version 02 files) and JNO‐J‐3‐FGM‐CAL‐V1.0 (Version 01 files), respectively. The Juno spacecraft trajectory information was obtained from the Laboratory for Atmospheric and Space Physics website( https://lasp.colorado.edu/home/mop/missions/juno/trajectory-information/ ). George Livadiotis contributed under NNX17AB74G NASA's grant for plasma‐magnetic field coupling.
Publisher Copyright:
©2020. American Geophysical Union. All Rights Reserved.
PY - 2020/4/1
Y1 - 2020/4/1
N2 - This study presents a survey of ion flow speed, density, temperature, and composition observed by the Jovian Auroral Distributions Experiment Ion (JADE-I) sensor on Juno from 10–40 RJ in the dawn to midnight sector of Jupiter's magnetosphere. The survey covers Juno orbits 5–22, and the observations are separated by equatorial (|zmag[RJ]| ≤ 1.5) and off-equator (|zmag[RJ]|>1.5) regions. Plasma parameters for H+, O+, O2+, O3+, Na+, S+, S2+, and S3+ are derived by forward modeling JADE-I's energy-per-charge versus time-of-flight spectra using omnidirectional averaged convected kappa distributions and modeled instrument responses. O+ and S2+ are resolved via a ray-tracing simulation based on carbon-foil-effects. The ion flow speed increases with radial distance and is comparable to rigid corotation speed out to ∼20 RJ. Ion number densities decrease with radial distance, the primary species being H+, O+, and S2+. The relative contribution of H+ and S2+ increases and decreases, respectively, in the off-equator regions, supporting the interpretation that the latitudinal distribution of ions is mass dependent. The O+ to S2+ and ΣOn+ to ΣSn+ number density ratios are variable, the 5 RJ bin averages for O+ to S2+ ranging from ∼0.75–1.5 (equator) and ∼1.1–1.8 (off-equator) and ΣOn+ to ΣSn+ from ∼0.6–0.9 (equator) and ∼0.8–1.1 (off-equator). Both proton and heavy ion temperatures show order of magnitude increases between 10 and 20 RJ and range from ∼100 eV to 10 keV and 1 keV to a few tens of keV, respectively.
AB - This study presents a survey of ion flow speed, density, temperature, and composition observed by the Jovian Auroral Distributions Experiment Ion (JADE-I) sensor on Juno from 10–40 RJ in the dawn to midnight sector of Jupiter's magnetosphere. The survey covers Juno orbits 5–22, and the observations are separated by equatorial (|zmag[RJ]| ≤ 1.5) and off-equator (|zmag[RJ]|>1.5) regions. Plasma parameters for H+, O+, O2+, O3+, Na+, S+, S2+, and S3+ are derived by forward modeling JADE-I's energy-per-charge versus time-of-flight spectra using omnidirectional averaged convected kappa distributions and modeled instrument responses. O+ and S2+ are resolved via a ray-tracing simulation based on carbon-foil-effects. The ion flow speed increases with radial distance and is comparable to rigid corotation speed out to ∼20 RJ. Ion number densities decrease with radial distance, the primary species being H+, O+, and S2+. The relative contribution of H+ and S2+ increases and decreases, respectively, in the off-equator regions, supporting the interpretation that the latitudinal distribution of ions is mass dependent. The O+ to S2+ and ΣOn+ to ΣSn+ number density ratios are variable, the 5 RJ bin averages for O+ to S2+ ranging from ∼0.75–1.5 (equator) and ∼1.1–1.8 (off-equator) and ΣOn+ to ΣSn+ from ∼0.6–0.9 (equator) and ∼0.8–1.1 (off-equator). Both proton and heavy ion temperatures show order of magnitude increases between 10 and 20 RJ and range from ∼100 eV to 10 keV and 1 keV to a few tens of keV, respectively.
KW - Jupiter
KW - ion composition
KW - ion plasma parameters
KW - plasma sheet
UR - http://www.scopus.com/inward/record.url?scp=85083919189&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85083919189&partnerID=8YFLogxK
U2 - 10.1029/2019JA027696
DO - 10.1029/2019JA027696
M3 - Article
AN - SCOPUS:85083919189
SN - 2169-9402
VL - 125
JO - Journal of Geophysical Research: Space Physics
JF - Journal of Geophysical Research: Space Physics
IS - 4
M1 - e2019JA027696
ER -