Abstract
With observations of Van Allen Probe A, in this letter we display a typical event where banded whistler waves shifted up their frequencies with frequency bands broadening as a response to the enhancement of solar wind dynamic pressure. Meanwhile, the anisotropy of electrons with energies about several tens of keV was observed to increase. Through the comparison of the calculated wave growth rates and observed wave spectral intensity, we suggest that those banded whistler waves observed with frequencies shifted up and frequency bands broadening could be locally excited by these hot electrons with increased anisotropy. The current study provides a great in situ evidence for the influence on frequencies of banded whistler waves by the enhancement of solar wind dynamic pressures, which reveals the important role of solar wind dynamic pressures playing in the frequency properties of banded whistler waves.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 8755-8763 |
| Number of pages | 9 |
| Journal | Geophysical Research Letters |
| Volume | 45 |
| Issue number | 17 |
| DOIs | |
| State | Published - Sep 16 2018 |
Bibliographical note
Funding Information:We acknowledge the Van Allen Probes data from the EMFISIS and HOPE instrument obtained from http:// emfisis.physics.uiowa.edu/data/index, and http://www.rbsp-ect.lanl.gov/data_ pub/, respectively. We thank Craig A. Kletzing for providing the data of the EMFISIS and advice on their usage. This work is supported by the National Natural Science Foundation of China (41374168, 41521063, 41604156, and 41874194) and Program for New Century Excellent Talents in University (NCET-13-0446).
Publisher Copyright:
©2018. American Geophysical Union. All Rights Reserved.
Keywords
- banded whistler mode waves
- frequency properties
- inner
- magnetosphere
- solar wind dynamic pressure
