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Title: Periodic Rising and Falling Tone ECH Waves From Van Allen Probes Observations
Abstract

Electron cyclotron harmonic (ECH) waves are known to precipitate plasma sheet electrons into the upper atmosphere and generate diffuse aurorae. In this study, we report quasiperiodic rising (3 events) and falling tone (22 events) ECH waves observed by Van Allen Probes and evaluate their properties. These rising and falling tone ECH waves prefer to occur during quiet geomagnetic conditions over the dusk to midnight sector in relatively high‐density (10–80 cm−3) regions. Their repetition periods increase with increasingLshell atL < 6, ranging from ∼60 to 110 s. The wave element duration varies from 10 to 130 s peaking at ∼40 s and the chirping rate peaks at ∼50 (∼−50) Hz/s for rising (falling) tones. Our findings reveal intriguing features of the ECH wave properties, which provide new insights into their generation and potential effects on electron precipitation.

 
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Award ID(s):
1847818
NSF-PAR ID:
10374435
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
48
Issue:
7
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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