On the wave-particle interaction and removal of energetic particles

There is always a risk of destruction of man-made satellites by the energetic electrons trapped in Van Allen radiation belts in space. These energetic electrons also pose a biological danger to astronauts. The cyclotron resonance interaction is studied between the whistler-mode waves in the frequency range of ELF (Extremely Low Frequency 300 – 3000 HZ) and VLF (Very Low Frequency 3 – 30 kHz) propagating along geomagnetic field line and counter streaming energetic electron. During this process the pitch angle of energetic electrons reduces. This results in the dumping of these electrons into the lower ionosphere. This makes electrons unable to strike the satellites orbiting in low Earth orbit, Geosynchronous, Sun-synchronous or polar orbit. It is shown that the lifetime values of energetic electrons vary from 2.03 to 227.68 hours at low latitudes. It is shown that these waves can remove these energetic electrons from their path and ensure the safety of satellites.

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Fluctuation of Lower Ionosphere Associated with Energetic Electron Precipitations during a Substorm

Atmosphere ◽

10.3390/atmos12050573 ◽

2021 ◽

Vol 12 (5) ◽

pp. 573

Author(s):

Tongxing Fu ◽

Zhixu Wu ◽

Peng Hu ◽

Xin Zhang

Keyword(s):

Radio Wave ◽

Current Sheet ◽

Geomagnetic Storm ◽

Particle Interaction ◽

Energetic Electron ◽

Lower Ionosphere ◽

Electron Precipitation ◽

Electron Interaction ◽

Energetic Electrons ◽

Tail Current

In this paper, using the combined observations of the NOAA 16, LANL-01A, IMAGE satellites, VLF radio wave, and ground-based riometers, we study the fluctuation of lower ionosphere-associated precipitating energetic electrons during a geomagnetic storm on 8 November 2004. Associated with the substorm dispersion injection observed by the LANL-01A satellite, the riometers observed obvious enhancements of ionospheric absorption within the electron isotropic zone, which they attributed to the tail current sheet scattering (TCS) mechanism. Through observations of the NOAA 16 satellite, we found a sharp enhancement of the precipitating electron flux within the anisotropic zone, which entailed an obvious separation of energetic electron precipitation at high latitudes. This energetic electron precipitation within the anisotropic zone leads to the significant enhancement of electron density in the D region, thus resulting in the variations of VLF radio wave amplitudes, which propagate in the middle latitudes. Since the projection of the electron precipitation region within the anisotropic zone is at the inner edge of the plasmapause observed by the IMAGE EUV, the precipitation of energetic electrons should be attributed to the ELF hiss-ring current electron interaction. As a result, the energetic electron precipitations due to the tail current sheet scattering mechanism and wave-particle interaction in the inner magnetosphere were both observed and analyzed as they were associated with a substorm during a geomagnetic storm.

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BeiDa Imaging Electron Spectrometer observation of multi-period electron flux modulation caused by localized ultra-low-frequency waves

Annales Geophysicae ◽

10.5194/angeo-38-801-2020 ◽

2020 ◽

Vol 38 (4) ◽

pp. 801-813

Author(s):

Xingran Chen ◽

Qiugang Zong ◽

Hong Zou ◽

Xuzhi Zhou ◽

Li Li ◽

...

Keyword(s):

Time Delay ◽

Electron Flux ◽

Particle Interaction ◽

Energetic Electron ◽

Low Frequency ◽

Particle Energy ◽

Energy Change ◽

Electron Spectrometer ◽

Resonance Theory ◽

Energy Channels

Abstract. We present multi-period modulation of energetic electron flux observed by the BeiDa Imaging Electron Spectrometer (BD-IES) on board a Chinese navigation satellite on 13 October 2015. Electron flux oscillations were observed at a dominant period of ∼190 s in consecutive energy channels from ∼50 to ∼200 keV. Interestingly, flux modulations at a secondary period of ∼400 s were also unambiguously observed. The oscillating signals at different energy channels were observed in sequence, with a time delay of up to ∼900 s. This time delay far exceeds the oscillating periods, by which we speculate that the modulations were caused by localized ultra-low-frequency (ULF) waves. To verify the wave–particle interaction scenario, we revisit the classic drift-resonance theory. We adopt the calculation method therein to derive the electron energy change in a multi-period ULF wave field. Then, based on the modeled energy change, we construct the flux variations to be observed by a virtual spacecraft. The predicted particle signatures well agree with the BD-IES observations. We demonstrate that the particle energy change might be underestimated in the conventional theories, as the Betatron acceleration induced by the curl of the wave electric field was often omitted. In addition, we show that azimuthally localized waves would notably extend the energy width of the resonance peak, whereas the drift-resonance interaction is only efficient for particles at the resonant energy in the original theory.

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Meteorological effects in the lower ionosphere as based on VLF/LF signal observations

Natural Hazards and Earth System Sciences Discussions ◽

10.5194/nhessd-2-2789-2014 ◽

2014 ◽

Vol 2 (4) ◽

pp. 2789-2812 ◽

Cited By ~ 2

Author(s):

A. Rozhnoi ◽

M. Solovieva ◽

B. Levin ◽

M. Hayakawa ◽

V. Fedun

Keyword(s):

Gravity Waves ◽

Atmospheric Pressure ◽

Low Frequency ◽

Lower Ionosphere ◽

Signal Amplitude ◽

Internal Gravity Waves ◽

Atmospheric Parameters ◽

Low Latitudes ◽

Far Eastern ◽

Meteorological Effects

Abstract. Very low and low frequency (VLF/LF) data recorded in the Far Eastern stations Petropavlovsk-Kamchatsky (158.92° E, 53.15° N), Yuzhno-Sakhalinsk (142.75° E, 46.95° N) and Yuzhno-Kurilsk (145.861° E, 44.03° N) are investigated to study the meteorological effects in the lower ionosphere. The results demonstrate the sensitivity of the VLF/LF signals to the variations of atmospheric pressure, humidity, wind velocity and temperature, and the VLF/LF record at the station of Yuzhno-Kurilsk is found to be most sensitive to those variations of atmospheric parameters. The region under consideration is characterized by high winter cyclonic activity in midlatitudes and strong summer and autumn typhoon activity in low latitudes. VLF/LF signal variations during 8 tropical cyclones (TCs) with different intensity are considered. Negative nighttime anomalies in the signal amplitude that are most probably caused by TC activity are found for 6 events. Those anomalies are observed during 1–2 days when TCs move inside the sensitivity zones of the subionospheric paths. Perturbations of the VLF signal observed during 2 TCs can be caused by both the TC influence and seismic activity, but no correlation between TC intensity and magnitude of the signal anomalies is found. Spectral analysis of the typhoon-induced disturbed signals revealed the fluctuations with time periods in the range of 7–16 and 15–55 min that corresponds to the range of internal gravity waves periods.

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Modeling whistler wave generation regimes in magnetospheric cyclotron maser

Annales Geophysicae ◽

10.5194/angeo-22-3561-2004 ◽

2004 ◽

Vol 22 (10) ◽

pp. 3561-3570 ◽

Cited By ~ 23

Author(s):

D. L. Pasmanik ◽

A. G. Demekhov ◽

V. Y. Trakhtengerts ◽

M. Parrot

Keyword(s):

Source Parameters ◽

Energetic Electron ◽

Low Frequency ◽

Wave Generation ◽

Whistler Wave ◽

Particle Precipitation ◽

Loss Cone ◽

Energetic Electrons ◽

Cyclotron Maser ◽

Different Characteristics

Abstract. Numerical analysis of the model for cyclotron instability in the Earth's magnetosphere is performed. This model, based on the self-consistent set of equations of quasi-linear plasma theory, describes different regimes of wave generation and related energetic particle precipitation. As the source of free energy the injection of energetic electrons with transverse anisotropic distribution function to the interaction region is considered. A parametric study of the model is performed. The main attention is paid to the analysis of generation regimes for different characteristics of energetic electron source, such as the shape of pitch angle distributions and its intensity. Two mechanisms of removal of energetic electrons from a generation region are considered, one is due to the particle precipitation through the loss cone and another one is related to the magnetic drift of energetic particles. It was confirmed that two main regimes occur in this system in the presence of a constant particle source, in the case of precipitation losses. At small source intensity relaxation oscillations were found, whose parameters are in good agreement with simplified analytical theory developed earlier. At a larger source intensity, transition to a periodic generation occurs. In the case of drift losses the regime of self-sustained periodic generation regime is realized for source intensity higher than some threshold. The dependencies of repetition period and dynamic spectrum shape on the source parameters were studied in detail. In addition to simple periodic regimes, those with more complex spectral forms were found. In particular, alteration of spikes with different spectral shape can take place. It was also shown that quasi-stationary generation at the low-frequency band can coexist with periodic modulation at higher frequencies. On the basis of the results obtained, the model for explanation of quasi-periodic whistler wave emissions is verified.

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Meteorological effects in the lower ionosphere as based on VLF/LF signal observations

Natural Hazards and Earth System Science ◽

10.5194/nhess-14-2671-2014 ◽

2014 ◽

Vol 14 (10) ◽

pp. 2671-2679 ◽

Cited By ~ 26

Author(s):

A. Rozhnoi ◽

M. Solovieva ◽

B. Levin ◽

M. Hayakawa ◽

V. Fedun

Keyword(s):

Gravity Waves ◽

Atmospheric Pressure ◽

Low Frequency ◽

Lower Ionosphere ◽

Signal Amplitude ◽

Internal Gravity Waves ◽

Atmospheric Parameters ◽

Low Latitudes ◽

Far Eastern ◽

Meteorological Effects

Abstract. Very low and low frequency (VLF/LF) data recorded in the Far Eastern stations Petropavlovsk-Kamchatsky (158.92° E, 53.15° N), Yuzhno-Sakhalinsk (142.75° E, 46.95° N) and Yuzhno-Kurilsk (145.861° E, 44.03° N) are investigated to study the meteorological effects in the lower ionosphere. The results demonstrate the sensitivity of the VLF/LF signals to the variations of atmospheric pressure, humidity, wind velocity and temperature, and the VLF/LF record at the station of Yuzhno-Kurilsk is found to be most sensitive to those variations of atmospheric parameters. The region under consideration is characterized by high winter cyclonic activity in mid-latitudes and strong summer and autumn typhoon activity in low latitudes. VLF/LF signal variations during eight tropical cyclones (TCs) with different intensity are considered. Negative nighttime anomalies in the signal amplitude that are most probably caused by TC activity are found for six events. Those anomalies are observed during 1–2 days when TCs move inside the sensitivity zones of the subionospheric paths. Perturbations of the VLF signal observed during two TCs can be caused by both the TC influence and seismic activity, but no correlation between TC intensity and magnitude of the signal anomalies is found. Spectral analysis of the typhoon-induced disturbed signals revealed the fluctuations with time periods in the range of 7–16 and 15–55 min that corresponds to the range of internal gravity waves periods.

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The very low-frequency transmitter radio wave anomalies related to the 2010 Ms 7.1 Yushu earthquake observed by the DEMETER satellite and the possible mechanism

Annales Geophysicae ◽

10.5194/angeo-38-969-2020 ◽

2020 ◽

Vol 38 (5) ◽

pp. 969-981

Author(s):

Shufan Zhao ◽

XuHui Shen ◽

Zeren Zhima ◽

Chen Zhou

Keyword(s):

Electric Field ◽

Electron Density ◽

Low Frequency ◽

Lower Ionosphere ◽

Satellite Observation ◽

Low Earth Orbit ◽

Electron Content ◽

Yushu Earthquake ◽

Total Electron ◽

Very Low Frequency

Abstract. Earthquakes may disturb the lower ionosphere through various coupling mechanisms during the seismogenic and coseismic periods. The VLF (very low-frequency) signal radiated from ground-based transmitters will be affected when it penetrates the disturbed ionosphere above the epicenter area, and this anomaly can be recorded by low-Earth orbit satellites under certain conditions. In this paper, the temporal and spatial variation of the signal-to-noise ratio (SNR) of the VLF transmitter signal in the ionosphere over the epicenter of 2010 Yushu Ms 7.1 earthquake in China is analyzed using DEMETER (Detection of Electro-Magnetic Emission Transmitted from Earthquake Regions) satellite observation. The results show that SNR over the epicenter of the Yushu earthquake especially in the southwestern region decreased (or dropped) before the main shock, and a GPS–TEC (Global Positioning System; total electron content) anomaly accompanied, which implies that the decrease in SNR might be caused by the enhancement of TEC. A full-wave method is used to study the mechanism of the change in SNR before the earthquake. The simulated results show SNR does not always decrease before an earthquake. When the electron density in the lower ionosphere increases by 3 times, the electric field will decrease about 2 dB, indicating that the disturbed-electric-field decrease of 20 % compared with the original electric field and vice versa. It can be concluded that the variation of electron density before earthquakes may be one of the important factors influencing the variation of SNR.

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Significance of Wave-Particle Interaction Analyzer for direct measurements of nonlinear wave-particle interactions

Annales Geophysicae ◽

10.5194/angeo-31-503-2013 ◽

2013 ◽

Vol 31 (3) ◽

pp. 503-512 ◽

Cited By ~ 16

Author(s):

Y. Katoh ◽

M. Kitahara ◽

H. Kojima ◽

Y. Omura ◽

S. Kasahara ◽

...

Keyword(s):

Kinetic Energy ◽

Velocity Vector ◽

Statistical Significance ◽

Particle Interaction ◽

Energetic Electron ◽

Particle Interactions ◽

Whistler Mode ◽

Wave Particle Interaction ◽

Energetic Electrons ◽

Wave Particle Interactions

Abstract. In the upcoming JAXA/ERG satellite mission, Wave Particle Interaction Analyzer (WPIA) will be installed as an onboard software function. We study the statistical significance of the WPIA for measurement of the energy transfer process between energetic electrons and whistler-mode chorus emissions in the Earth's inner magnetosphere. The WPIA measures a relative phase angle between the wave vector E and velocity vector v of each electron and computes their inner product W, where W is the time variation of the kinetic energy of energetic electrons interacting with plasma waves. We evaluate the feasibility by applying the WPIA analysis to the simulation results of whistler-mode chorus generation. We compute W using both a wave electric field vector observed at a fixed point in the simulation system and a velocity vector of each energetic electron passing through this point. By summing up Wi of an individual particle i to give Wint, we obtain significant values of Wint as expected from the evolution of chorus emissions in the simulation result. We can discuss the efficiency of the energy exchange through wave-particle interactions by selecting the range of the kinetic energy and pitch angle of the electrons used in the computation of Wint. The statistical significance of the obtained Wint is evaluated by calculating the standard deviation σW of Wint. In the results of the analysis, positive or negative Wint is obtained at the different regions of velocity phase space, while at the specific regions the obtained Wint values are significantly greater than σW, indicating efficient wave-particle interactions. The present study demonstrates the feasibility of using the WPIA, which will be on board the upcoming ERG satellite, for direct measurement of wave-particle interactions.

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Storm-Time Features of the Ionospheric ELF/VLF Waves and Energetic Electron Fluxes Revealed by the China Seismo-Electromagnetic Satellite

Applied Sciences ◽

10.3390/app11062617 ◽

2021 ◽

Vol 11 (6) ◽

pp. 2617

Author(s):

Zeren Zhima ◽

Yunpeng Hu ◽

Xuhui Shen ◽

Wei Chu ◽

Mirko Piersanti ◽

...

Keyword(s):

Geomagnetic Activity ◽

Radiation Belt ◽

Energetic Electron ◽

Outer Radiation Belt ◽

Whistler Mode ◽

Energetic Electrons ◽

Intense Storm ◽

Storm Evolution ◽

Whistler Mode Waves ◽

Vlf Waves

This study reports the temporal and spatial distributions of the extremely/very low frequency (ELF/VLF) wave activities and the energetic electron fluxes in the ionosphere during an intense storm (geomagnetic activity index Dst of approximately −174 nT) that occurred on 26 August 2018, based on the observations by a set of detectors onboard the China Seismo-Electromagnetic Satellite (CSES). A good correlation of the ionospheric ELF/VLF wave activities with energetic electron precipitations during the various storm evolution phases was revealed. The strongest ELF/VLF emissions at a broad frequency band extending up to 20 kHz occurred from the near-end main phase to the early recovery phase of the storm, while the wave activities mainly appeared at the frequency range below 6 kHz during other phases. Variations in the precipitating fluxes were also spotted in correspondence with changing geomagnetic activity, with the max values primarily appearing outside of the plasmapause during active conditions. The energetic electrons at energies below 1.5 MeV got strong enhancements during the whole storm time on both the day and night side. Examinations of the half-orbit data showed that under the quiet condition, the CSES was able to depict the outer/inner radiation belt as well as the slot region well, whereas under disturbed conditions, such regions became less sharply defined. The regions poleward from geomagnetic latitudes over 50° were found to host the most robust electron precipitation regardless of the quiet or active conditions, and in the equatorward regions below 30°, flux enhancements were mainly observed during storm time and only occasionally in quiet time. The nightside ionosphere also showed remarkable temporal variability along with the storm evolution process but with relatively weaker wave activities and similar level of fluxes enhancement compared to the ones in the dayside ionosphere. The ELF/VLF whistler-mode waves recorded by the CSES mainly included structure-less VLF waves, structured VLF quasi-periodic emissions, and structure-less ELF hiss waves. A wave vector analysis showed that during storm time, these ELF/VLF whistler-mode waves obliquely propagated, mostly likely from the radiation belt toward the Earth direction. We suggest that energetic electrons in the high latitude ionosphere are most likely transported from the outer radiation belt as a consequence of their interactions with ELF/VLF waves.

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Correlations between very low frequency chorus bursts and impulsive magnetic variations at L ~ 4.5

Canadian Journal of Physics ◽

10.1139/p81-136 ◽

1981 ◽

Vol 59 (8) ◽

pp. 1034-1041 ◽

Cited By ~ 11

Author(s):

S. Kokubun ◽

K. Hayashi ◽

T. Oguti ◽

K. Tsuruda ◽

S. Machida ◽

...

Keyword(s):

Low Frequency ◽

Frequency Range ◽

Conductivity Enhancement ◽

Very Low Frequency ◽

Close Relationship ◽

Magnetic Pulsations ◽

Whistler Mode Waves ◽

Short Time ◽

Vlf Emissions ◽

Vlf Waves

Coordinated observations of aurora, ULF, and VLF waves were made at 13 stations in Canada in January and February, 1980. The analysis of simultaneous ULF and VLF data obtained at Park Site (L = 4.4) revealed a close relationship between irregular magnetic pulsations and VLF emissions in the frequency range of 1.5–5 kHz. One-to-one correlations were observed between VLF chorus bursts and impulsive magnetic variations, called magnetic impulses, during sub-storms of Kp ≥ 4+ on the local morning-to-noon side. VLF chorus bursts consist of discrete risers of 0.1–0.3 s duration. It is found that magnetic impulses with a rise time of 0.5–1 s and with a duration of ~2 s coincide with the occurrence of VLF riser groups of a similar duration within ~2 s. This short time difference strongly suggests that magnetic impulses are caused by a conductivity enhancement due to electron precipitation induced by whistler mode waves.

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Wave and plasma measurements and GPS diagnostics of the main ionospheric trough as a hybrid method used for Space Weather purposes

Annales Geophysicae ◽

10.5194/angeo-26-295-2008 ◽

2008 ◽

Vol 26 (2) ◽

pp. 295-304 ◽

Cited By ~ 6

Author(s):

H. Rothkaehl ◽

A. Krakowski ◽

I. Stanislawska ◽

J. Błęcki ◽

M. Parrot ◽

...

Keyword(s):

Space Weather ◽

Acoustic Waves ◽

Particle Interaction ◽

Low Frequency ◽

Wave Activity ◽

Geomagnetic Disturbances ◽

Geomagnetic Field Line ◽

Unique Region ◽

Main Ionospheric Trough ◽

Plasma Measurements

Abstract. The region of the main ionospheric trough is a unique region of the ionosphere, where different types of waves and instabilities can be generated. This region of the ionosphere acts like a lens, focusing a variety of indicators from the equator of plasmapause and local ionospheric plasma. This paper reports the results of monitoring the mid-latitude trough structure, dynamics and wave activity. For these purposes, the data gathered by the currently-operating DEMETER satellite and past diagnostics located on IK-19, Apex, and MAGION-3 spacecraft, as well as TEC measurements were used. A global-time varying picture of the ionospheric trough was reconstructed using the sequence of wave spectra registered and plasma measurements in the top-side ionosphere. The authors present the wave activity from ULF frequency band to the HF frequency detected inside the trough region and discuss its properties during geomagnetic disturbances. It is thought that broadband emissions are correlated with low frequency radiation, which is excited by the wave-particle interaction in the equatorial plasmapause and moves to the ionosphere along the geomagnetic field line. In the ionosphere, the suprathermal electrons can interact with these electrostatic waves and excite electron acoustic waves or HF longitudinal plasma waves. Furthermore, the electron density trough can provide useful data on the magnetosphere ionosphere dynamics and morphology and, in consequence, can be used for Space Weather purposes.

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