In situ Observations of Whistler-mode Chorus Waves Guided by Density Ducts

Author
Keywords
Abstract
Abstract In this paper, we report the proof of the existence of density ducts in the Earth’s magnetosphere by studying in situ observations of whistler-mode chorus waves using NASA’s Van Allen Probe-A data. Chorus waves, originally excited inside the density ducts with wave normal angles (WNAs) smaller than the Gendrin angle at near equator region, are efficiently confined to a limited area inside density ducts (i.e., ducted regions), and remain with small WNAs as they propagate towards high latitudes. The ducted region becomes narrower for the higher-frequency waves. Chorus waves with WNAs larger than the Gendrin angle are not guided by density ducts. Our study reveals that density ducts can effectively control the property and distribution of chorus waves, and may ultimately regulate electron dynamics in the Earth’s or other planetary radiation belts. This article is protected by copyright. All rights reserved.
Notes
Year of Publication
2021
Journal
Journal of Geophysical Research: Space Physics
Volume
n/a
Number
Number of Pages
e2020JA028814
Date Published
03/2021
URL
https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2020JA028814
DOI
https://doi.org/10.1029/2020JA028814