Analysis of Whistler-Mode and Z-Mode Emission in the Juno Primary Mission

J. D. Menietti; T. F. Averkamp; W. S. Kurth; M. Imai; J. B. Faden; G. B. Hospodarsky; O. Santolik; G. Clark; F. Allegrini; S. S. Elliott; A. H. Sulaiman; S. J. Bolton

doi:10.1029/2021JA029885

Analysis of Whistler-Mode and Z-Mode Emission in the Juno Primary Mission

J. D. Menietti, T. F. Averkamp, W. S. Kurth, M. Imai, J. B. Faden, G. B. Hospodarsky, O. Santolik, G. Clark, F. Allegrini, S. S. Elliott, A. H. Sulaiman, S. J. Bolton

Research output: Contribution to journal › Article › peer-review

6 Scopus citations

Abstract

At the end of the Juno primary mission, we report observations of whistler mode chorus and Z-mode emission. The Juno orbits are evolving and much better coverage of the whistler mode chorus source region has resulted since the earlier surveys. Bursty chorus emission extending to ∼30° latitude and to frequencies less than the lower hybrid frequency near the source region imply high electron energies (>100 keV). Average chorus intensity levels peak at ∼10⁻³ nT² near M-shell of 8–9 and magnetic latitude of ∼5°. Z-mode emission is identified at higher latitudes generally near and inward of the Io torus with intensity levels as much as two orders of magnitude higher than Z-mode emissions observed at Saturn. Inferred source regions for the Z-mode are consistent with the inner edge of the Io torus and with auroral field lines that may also support Jovian kilometric and decametric emission. Parametric fitting functions are evaluated for both whistler mode chorus and Z-mode, describing wave intensity as a function of frequency, magnetic latitude, and M-shell. Both whistler mode and Z-mode waves may have significant impact on electron scattering and acceleration at Jupiter as recent models indicate.

Original language	English (US)
Article number	e2021JA029885
Journal	Journal of Geophysical Research: Space Physics
Volume	126
Issue number	11
DOIs	https://doi.org/10.1029/2021JA029885
State	Published - Nov 2021
Externally published	Yes

Bibliographical note

Funding Information:
The authors wish to thank K. Kurth for clerical assistance and J. Chrisinger for help with the figures, and P. Kollmann for providing JEDI pitch angle data. JDM acknowledges support from NASA grant 80NSSC19K1262. Research conducted at the University of Iowa was supported by NASA New Frontiers Program through Contract 699041X with Southwest Research Institute. The work of MI was supported by the JSPS KAKENHI Grant Number JP20K22371. G. Clark and F. Allegrini were funded by NASA New Frontiers Program for Juno (for G. Clark this was through a subcontract with Southwest Research Institute). OS acknowledges support from the LTAUSA17070 Inter‐Excellence Project.

Publisher Copyright:
© 2021. American Geophysical Union. All Rights Reserved.

Keywords

Juno
Jupiter
magnetospheric physics
whistler mode emissions

Access

10.1029/2021JA029885

OpenUrl availability

Full text

Cite this

Menietti, J. D., Averkamp, T. F., Kurth, W. S., Imai, M., Faden, J. B., Hospodarsky, G. B., Santolik, O., Clark, G., Allegrini, F., Elliott, S. S., Sulaiman, A. H., & Bolton, S. J. (2021). Analysis of Whistler-Mode and Z-Mode Emission in the Juno Primary Mission. Journal of Geophysical Research: Space Physics, 126(11), Article e2021JA029885. https://doi.org/10.1029/2021JA029885

@article{0d6bb60249884c26bc043b936cd3446f,

title = "Analysis of Whistler-Mode and Z-Mode Emission in the Juno Primary Mission",

abstract = "At the end of the Juno primary mission, we report observations of whistler mode chorus and Z-mode emission. The Juno orbits are evolving and much better coverage of the whistler mode chorus source region has resulted since the earlier surveys. Bursty chorus emission extending to ∼30° latitude and to frequencies less than the lower hybrid frequency near the source region imply high electron energies (>100 keV). Average chorus intensity levels peak at ∼10−3 nT2 near M-shell of 8–9 and magnetic latitude of ∼5°. Z-mode emission is identified at higher latitudes generally near and inward of the Io torus with intensity levels as much as two orders of magnitude higher than Z-mode emissions observed at Saturn. Inferred source regions for the Z-mode are consistent with the inner edge of the Io torus and with auroral field lines that may also support Jovian kilometric and decametric emission. Parametric fitting functions are evaluated for both whistler mode chorus and Z-mode, describing wave intensity as a function of frequency, magnetic latitude, and M-shell. Both whistler mode and Z-mode waves may have significant impact on electron scattering and acceleration at Jupiter as recent models indicate.",

keywords = "Juno, Jupiter, magnetospheric physics, whistler mode emissions",

author = "Menietti, {J. D.} and Averkamp, {T. F.} and Kurth, {W. S.} and M. Imai and Faden, {J. B.} and Hospodarsky, {G. B.} and O. Santolik and G. Clark and F. Allegrini and Elliott, {S. S.} and Sulaiman, {A. H.} and Bolton, {S. J.}",

note = "Funding Information: The authors wish to thank K. Kurth for clerical assistance and J. Chrisinger for help with the figures, and P. Kollmann for providing JEDI pitch angle data. JDM acknowledges support from NASA grant 80NSSC19K1262. Research conducted at the University of Iowa was supported by NASA New Frontiers Program through Contract 699041X with Southwest Research Institute. The work of MI was supported by the JSPS KAKENHI Grant Number JP20K22371. G. Clark and F. Allegrini were funded by NASA New Frontiers Program for Juno (for G. Clark this was through a subcontract with Southwest Research Institute). OS acknowledges support from the LTAUSA17070 Inter‐Excellence Project. Publisher Copyright: {\textcopyright} 2021. American Geophysical Union. All Rights Reserved.",

year = "2021",

month = nov,

doi = "10.1029/2021JA029885",

language = "English (US)",

volume = "126",

journal = "Journal of Geophysical Research: Space Physics",

issn = "2169-9380",

number = "11",

}

TY - JOUR

T1 - Analysis of Whistler-Mode and Z-Mode Emission in the Juno Primary Mission

AU - Menietti, J. D.

AU - Averkamp, T. F.

AU - Kurth, W. S.

AU - Imai, M.

AU - Faden, J. B.

AU - Hospodarsky, G. B.

AU - Santolik, O.

AU - Clark, G.

AU - Allegrini, F.

AU - Elliott, S. S.

AU - Sulaiman, A. H.

AU - Bolton, S. J.

N1 - Funding Information: The authors wish to thank K. Kurth for clerical assistance and J. Chrisinger for help with the figures, and P. Kollmann for providing JEDI pitch angle data. JDM acknowledges support from NASA grant 80NSSC19K1262. Research conducted at the University of Iowa was supported by NASA New Frontiers Program through Contract 699041X with Southwest Research Institute. The work of MI was supported by the JSPS KAKENHI Grant Number JP20K22371. G. Clark and F. Allegrini were funded by NASA New Frontiers Program for Juno (for G. Clark this was through a subcontract with Southwest Research Institute). OS acknowledges support from the LTAUSA17070 Inter‐Excellence Project. Publisher Copyright: © 2021. American Geophysical Union. All Rights Reserved.

PY - 2021/11

Y1 - 2021/11

N2 - At the end of the Juno primary mission, we report observations of whistler mode chorus and Z-mode emission. The Juno orbits are evolving and much better coverage of the whistler mode chorus source region has resulted since the earlier surveys. Bursty chorus emission extending to ∼30° latitude and to frequencies less than the lower hybrid frequency near the source region imply high electron energies (>100 keV). Average chorus intensity levels peak at ∼10−3 nT2 near M-shell of 8–9 and magnetic latitude of ∼5°. Z-mode emission is identified at higher latitudes generally near and inward of the Io torus with intensity levels as much as two orders of magnitude higher than Z-mode emissions observed at Saturn. Inferred source regions for the Z-mode are consistent with the inner edge of the Io torus and with auroral field lines that may also support Jovian kilometric and decametric emission. Parametric fitting functions are evaluated for both whistler mode chorus and Z-mode, describing wave intensity as a function of frequency, magnetic latitude, and M-shell. Both whistler mode and Z-mode waves may have significant impact on electron scattering and acceleration at Jupiter as recent models indicate.

AB - At the end of the Juno primary mission, we report observations of whistler mode chorus and Z-mode emission. The Juno orbits are evolving and much better coverage of the whistler mode chorus source region has resulted since the earlier surveys. Bursty chorus emission extending to ∼30° latitude and to frequencies less than the lower hybrid frequency near the source region imply high electron energies (>100 keV). Average chorus intensity levels peak at ∼10−3 nT2 near M-shell of 8–9 and magnetic latitude of ∼5°. Z-mode emission is identified at higher latitudes generally near and inward of the Io torus with intensity levels as much as two orders of magnitude higher than Z-mode emissions observed at Saturn. Inferred source regions for the Z-mode are consistent with the inner edge of the Io torus and with auroral field lines that may also support Jovian kilometric and decametric emission. Parametric fitting functions are evaluated for both whistler mode chorus and Z-mode, describing wave intensity as a function of frequency, magnetic latitude, and M-shell. Both whistler mode and Z-mode waves may have significant impact on electron scattering and acceleration at Jupiter as recent models indicate.

KW - Juno

KW - Jupiter

KW - magnetospheric physics

KW - whistler mode emissions

UR - http://www.scopus.com/inward/record.url?scp=85119872449&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85119872449&partnerID=8YFLogxK

U2 - 10.1029/2021JA029885

DO - 10.1029/2021JA029885

M3 - Article

AN - SCOPUS:85119872449

SN - 2169-9380

VL - 126

JO - Journal of Geophysical Research: Space Physics

JF - Journal of Geophysical Research: Space Physics

IS - 11

M1 - e2021JA029885

ER -

Analysis of Whistler-Mode and Z-Mode Emission in the Juno Primary Mission

Abstract

Bibliographical note

Keywords

Access

OpenUrl availability

Other files and links

Fingerprint

Cite this