Statistical Results of the Power Gap Between Lower‐Band and Upper‐Band Chorus Waves
Abstract
The primary power gap of chorus waves is statistically investigated using 7‐year waveform data from THEMIS probes for the first time. Overall, ~2/3 of chorus events have a power gap between the lower and upper bands. Both the gap frequency and the frequency bandwidth of the gap have a broad distribution, which peaks at frequencies of ~0.49fce and ~0.07fce, respectively. The gap frequency tends to increase with increasing |MLAT| (magnetic latitude), while the frequency width gradually increases with L‐shell. In most of banded events, the peak frequency of upper band is roughly twice that of lower band. Two types of events are studied. For Type I events, one population is located around Pup/Plow = 10−1, and the other is around Pup/Plow = 10−3. However, Type II events are roughly concentrated around Pup/Plow = 10−3. The gap frequency positively correlates with the frequency of upper band. Our study provides detailed observational constraints on potential mechanisms of the power gap formation.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 23, 2019
- Source ID
- 10.1029/2019gl082140
Entities
People
- Lunjin Chen
- Quanming Lu
- Shui Wang
- Wen Li
- Xinliang Gao
Organizations
- Air Force Office of Scientific Research
- Boston University
- National Natural Science Foundation of China
- University of Science and Technology of China
- University of Texas at Dallas
- Youth Innovation Promotion Association