A multispacecraft event study of Pc5 ultralow-frequency waves in the magnetosphere and their external drivers

Chih Ping Wang, Richard Thorne, Terry Z. Liu, Michael D. Hartinger, Tsugunobu Nagai, Vassilis Angelopoulos, John R. Wygant, Aaron Breneman, Craig Kletzing, Geoffrey D. Reeves, Seth G. Claudepierre, Harlan E. Spence

Research output: Contribution to journalArticle

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Abstract

We investigate a quiet time event of magnetospheric Pc5 ultralow-frequency (ULF) waves and their likely external drivers using multiple spacecraft observations. Enhancements of electric and magnetic field perturbations in two narrow frequency bands, 1.5–2 mHz and 3.5–4 mHz, were observed over a large radial distance range from r ~ 5 to 11 RE. During the first half of this event, perturbations were mainly observed in the transverse components and only in the 3.5–4 mHz band. In comparison, enhancements were stronger during the second half in both transverse and compressional components and in both frequency bands. No indication of field line resonances was found for these magnetic field perturbations. Perturbations in these two bands were also observed in the magnetosheath, but not in the solar wind dynamic pressure perturbations. For the first interval, good correlations between the flow perturbations in the magnetosphere and magnetosheath and an indirect signature for Kelvin-Helmholtz (K-H) vortices suggest K-H surface waves as the driver. For the second interval, good correlations are found between the magnetosheath dynamic pressure perturbations, magnetopause deformation, and magnetospheric waves, all in good correspondence to interplanetary magnetic field (IMF) discontinuities. The characteristics of these perturbations can be explained by being driven by foreshock perturbations resulting from these IMF discontinuities. This event shows that even during quiet periods, K-H-unstable magnetopause and ion foreshock perturbations can combine to create a highly dynamic magnetospheric ULF wave environment.

Original languageEnglish (US)
Pages (from-to)5132-5147
Number of pages16
JournalJournal of Geophysical Research: Space Physics
Volume122
Issue number5
DOIs
StatePublished - May 1 2017

Fingerprint

Magnetosphere
extremely low frequencies
magnetic fields
magnetospheres
magnetosphere
Magnetopause
perturbation
Magnetic fields
Frequency bands
magnetosheath
Solar wind
magnetic field
electric field
foreshock
Surface waves
dynamic pressure
magnetopause
interplanetary magnetic fields
Spacecraft
Vortex flow

Keywords

  • IMF discontinuity
  • Kelvin-Helmholtz vortices
  • Pc5 waves
  • inner magnetosphere
  • magnetosheath
  • plasma sheet

Cite this

Wang, C. P., Thorne, R., Liu, T. Z., Hartinger, M. D., Nagai, T., Angelopoulos, V., ... Spence, H. E. (2017). A multispacecraft event study of Pc5 ultralow-frequency waves in the magnetosphere and their external drivers. Journal of Geophysical Research: Space Physics, 122(5), 5132-5147. https://doi.org/10.1002/2016JA023610

A multispacecraft event study of Pc5 ultralow-frequency waves in the magnetosphere and their external drivers. / Wang, Chih Ping; Thorne, Richard; Liu, Terry Z.; Hartinger, Michael D.; Nagai, Tsugunobu; Angelopoulos, Vassilis; Wygant, John R.; Breneman, Aaron; Kletzing, Craig; Reeves, Geoffrey D.; Claudepierre, Seth G.; Spence, Harlan E.

In: Journal of Geophysical Research: Space Physics, Vol. 122, No. 5, 01.05.2017, p. 5132-5147.

Research output: Contribution to journalArticle

Wang, CP, Thorne, R, Liu, TZ, Hartinger, MD, Nagai, T, Angelopoulos, V, Wygant, JR, Breneman, A, Kletzing, C, Reeves, GD, Claudepierre, SG & Spence, HE 2017, 'A multispacecraft event study of Pc5 ultralow-frequency waves in the magnetosphere and their external drivers', Journal of Geophysical Research: Space Physics, vol. 122, no. 5, pp. 5132-5147. https://doi.org/10.1002/2016JA023610
Wang, Chih Ping ; Thorne, Richard ; Liu, Terry Z. ; Hartinger, Michael D. ; Nagai, Tsugunobu ; Angelopoulos, Vassilis ; Wygant, John R. ; Breneman, Aaron ; Kletzing, Craig ; Reeves, Geoffrey D. ; Claudepierre, Seth G. ; Spence, Harlan E. / A multispacecraft event study of Pc5 ultralow-frequency waves in the magnetosphere and their external drivers. In: Journal of Geophysical Research: Space Physics. 2017 ; Vol. 122, No. 5. pp. 5132-5147.
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AU - Angelopoulos, Vassilis

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AU - Breneman, Aaron

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KW - magnetosheath

KW - plasma sheet

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