Found 4 entries in the Bibliography.

Showing entries from 1 through 4


Periodic Rising and Falling Tone ECH Waves from Van Allen Probes Observations

AbstractElectron cyclotron harmonic (ECH) waves are known to precipitate plasma sheet electrons into the upper atmosphere and generate diffuse aurorae. In this study, we report quasi-periodic 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 incre ...

Shen, Xiao-Chen; Li, Wen; Ma, Qianli;

YEAR: 2021     DOI:

ECH wave; falling tone; rising tone; Magnetosphere; plasma wave; Van Allen Probes


Direct observation of generation and propagation of magnetosonic waves following substorm injection

Magnetosonic whistler mode waves play an important role in the radiation belt electron dynamics. Previous theory has suggested that these waves are excited by the ring distributions of hot protons and can propagate radially and azimuthally over a broad spatial range. However, because of the challenging requirements on satellite locations and data-processing techniques, this theory was difficult to validate directly. Here we present some experimental tests of the theory on the basis of Van Allen Probes observations of magneto ...

Su, Zhenpeng; Wang, Geng; Liu, Nigang; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2017     DOI: 10.1002/2017GL074362

Bernstein mode instability; magnetosonic waves; Radiation belt; rising tone; substorm injection; Van Allen Probes; Wave-particle interaction

Van Allen Probes observations of whistler-mode chorus with long-lived oscillating tones

Whistler-mode chorus plays an important role in the radiation belt electron dynamics. In the frequency-time spectrogram, chorus often appears as a hiss-like band and/or a series of short-lived (up to \~1 s) discrete elements. Here we present some rarely reported chorus emissions with long-lived (up to 25 s) oscillating tones observed by the Van Allen Probes in the dayside (MLT \~9\textendash14) midlatitude (|MLAT|>15\textdegree) region. An oscillating tone can behave either regularly or irregularly and can even transform int ...

Gao, Zhonglei; Su, Zhenpeng; Chen, Lunjin; Zheng, Huinan; Wang, Yuming; Wang, Shui;

YEAR: 2017     DOI: 10.1002/2017GL073420

Chorus; falling tone; nonlinear generation; oscillating tone; rising tone; Van Allen Probes


First observation of rising-tone magnetosonic waves

Magnetosonic (MS) waves are linearly polarized emissions confined near the magnetic equator with wave normal angle near 90\textdegree and frequency below the lower hybrid frequency. Such waves, also termed equatorial noise, were traditionally known to be \textquotedbllefttemporally continuous\textquotedblright in their time-frequency spectrogram. Here we show for the first time that MS waves actually have discrete wave elements with rising-tone features in their spectrogram. The frequency sweep rate of MS waves, ~1 Hz/s, is ...

Fu, H.; Cao, J.; Zhima, Z.; Khotyaintsev, Y.; Angelopoulos, V.; ik, O.; Omura, Y.; Taubenschuss, U.; Chen, L.; . Y. Huang, S;

YEAR: 2014     DOI: 10.1002/grl.v41.2110.1002/2014GL061867

discrete; frequency sweep rate; magnetosonic wave; nonlinear wave-particle interaction; Plasmapause; rising tone