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Title: Fine Structure of Magnetospheric Magnetosonic Waves: 1. Elementary Rising‐Tone Emissions Within Individual Harmonic
The present study uncovers the fine structures of magnetosonic waves by investigating the EFW waveforms measured by Van Allen Probes. We show that each harmonic of the magnetosonic wave may consist of a series of elementary rising‐tone emissions, implying a nonlinear mechanism for the wave generation. By investigating an elementary rising‐tone magnetosonic wave that spans a wide frequency range, we show that the frequency sweep rate is likely proportional to the wave frequency. We studied compound rising‐tone magnetosonic waves, and found that they typically consist of multiple harmonics in the source region, and may gradually become continuous in frequency as they propagate away from source. Both elementary and compound rising‐tone magnetosonic waves last for ∼1 min which is close to the bounce period of the ring proton distribution, but their relation is not fully understood.  more » « less
Award ID(s):
2247256
PAR ID:
10508761
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Journal of Geophysical Research: Space Physics
Date Published:
Journal Name:
Journal of Geophysical Research: Space Physics
Edition / Version:
1
Volume:
129
Issue:
3
ISSN:
2169-9380
Page Range / eLocation ID:
e2024JA032462
Format(s):
Medium: X Other: pdf
Sponsoring Org:
National Science Foundation
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