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Found 7 entries in the Bibliography.
Showing entries from 1 through 7
| 2021 |
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A statistical analysis of duration and frequency chirping rate of falling tone chorus AbstractThe duration (τ) and chirping rate (Γ) of whistler mode chorus waves are two of the most important properties to understand chorus generation mechanism and to quantify effects of nonlinear wave particle interactions on radiation belt electron acceleration. In this study, we perform the first statistical analysis of the duration and chirping rate of falling tone chorus elements using Van Allen Probes data.We found that τ increases and Γ decreases with increasing L-shell, although the dependence is weak. The durati ... Xie, Yi; Teng, Shangchun; Wu, Yifan; Tao, Xin; Published by: Geophysical Research Letters Published on: 09/2021 YEAR: 2021 DOI: https://doi.org/10.1029/2021GL095349 chorus waves; falling tone; Frequency chirping; Van Allen Probes |
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Abstract Magnetosonic (MS) waves and Electromagnetic ion cyclotron (EMIC) waves are important plasma waves in the magnetosphere. Using the Van Allen Probes observations from 2012 to 2017, we constructed the global distribution of simultaneous occurrence of MS and EMIC waves. We found a total of 214 events, and the waves distribute from the noon sector to the duskside. Furthermore, we quantitatively analyze the combined effects of both waves on protons and electrons by calculating of particle diffusion coefficients and 2-D Fo ... Published by: Geophysical Research Letters Published on: 08/2021 YEAR: 2021 DOI: https://doi.org/10.1029/2021GL093885 EMIC waves; MS waves; Wave-particle interaction; diffusion coefficients; Van Allen Probes |
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Characteristics of low-harmonic magnetosonic waves in the Earth’s inner magnetosphere Abstract Magnetosonic (MS) waves are electromagnetic waves that play important roles in the acceleration and scattering of radiation belt electrons. However, previous statistical analyses of the global MS wave distribution were mainly restricted to magnetic field measurements. In this study, we first report a low-harmonic MS wave event observed only by the electric field instrument of Van Allen Probes. The MS wave frequencies follow the local proton gyrofrequency (fcp), which suggests the characteristics of nearly local gene ... Teng, S.; Liu, N.; Ma, Q.; Tao, X.; Published by: Geophysical Research Letters Published on: 04/2021 YEAR: 2021 DOI: https://doi.org/10.1029/2021GL093119 Low-frequency magnetosonic wave; wave generation; Magnetosonic wave spectra; Van Allen Probes |
| 2019 |
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Characteristics and Generation of Low-Frequency Magnetosonic Waves Below the Proton Gyrofrequency We report a Van Allen Probes observation of large-amplitude magnetosonic waves with the peak intensity below the proton gyrofrequency (fcp), which may potentially be misinterpreted as electromagnetic ion cyclotron waves. The frequency spacing of the wave harmonic structure suggests that these magnetosonic waves are excited at a distant source region and propagate radially inward. We also conduct a statistical analysis of low-frequency magnetosonic waves below fcp based on the Van Allen Probes data from October 2012 to Decemb ... Teng, Shangchun; Li, Wen; Tao, Xin; Ma, Qianli; Shen, Xiaochen; Published by: Geophysical Research Letters Published on: 10/2019 YEAR: 2019 DOI: 10.1029/2019GL085372 Below the proton gyrofrequency; Low frequency magnetosonic wave; Van Allen Probes; wave generation; Wave propagation characteristics |
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Properties of banded, no-gap, lower band only, and upper band only whistler mode waves (0.1\textendash0.8fce) outside the plasmasphere are investigated using Van Allen Probes data. Our analysis shows that no-gap whistler waves have higher occurrence rate at morning side and dayside, while banded and lower band only waves have higher occurrence rate between midnight and dawn. We also find that the occurrence rate of no-gap whistler waves peaks at magnetic latitude |MLAT|\~8\textendash10\textdegree, while banded waves have hig ... Published by: Geophysical Research Letters Published on: 03/2019 YEAR: 2019 DOI: 10.1029/2019GL082161 banded whistler waves; chorus waves; no-gap whistler waves; Van Allen Probes |
| 2018 |
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Observation of Oblique Lower Band Chorus Generated by Nonlinear Three-Wave Interaction Oblique whistler mode waves have been suggested to play an important role in radiation belt electron dynamics. Recently, Fu et al. [2017] proposed that highly oblique lower band whistler waves could be generated by nonlinear three-wave resonance. Here we present the first observational evidence of such process, using Van Allen Probes data, where an oblique lower band chorus wave is generated by two quasi-parallel waves through nonlinear three-wave interaction. The wave resonance condition is satisfied even in the presence of ... Teng, S.; Zhao, J.; Tao, X.; Wang, S.; Reeves, G.; Published by: Geophysical Research Letters Published on: 06/2018 YEAR: 2018 DOI: 10.1029/2018GL078765 Oblique lower band chorus; radiation belt physics; Van Allen Probes; wave particle interaction; wave-wave interaction |
| 2017 |
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Analysis of the Duration of Rising Tone Chorus Elements The duration of chorus elements is an important parameter to understand chorus excitation and to quantify the effects of nonlinear wave-particle interactions on energetic electron dynamics. In this work, we analyze the duration of rising tone chorus elements statistically using Van Allen Probes data. We present the distribution of chorus element duration (τ) as a function of magnetic local time (MLT) and the geomagnetic activity level characterized by auroral electrojet (AE) index. We show that the typical value of τ for n ... Teng, S.; Tao, X.; Xie, Y.; Zonca, F.; Chen, L.; Fang, W.; Wang, S.; Published by: Geophysical Research Letters Published on: 12/2017 YEAR: 2017 DOI: 10.1002/2017GL075824 chorus element duration; DAWN; frequency chirping rate; Van Allen Probes |
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