scholarly journals Rapid Loss of Radiation Belt Relativistic Electrons by EMIC Waves

2017 ◽  
Vol 122 (10) ◽  
pp. 9880-9897 ◽  
Author(s):  
Zhenpeng Su ◽  
Zhonglei Gao ◽  
Huinan Zheng ◽  
Yuming Wang ◽  
Shui Wang ◽  
...  
Keyword(s):  
Radiation Belt ◽  
Relativistic Electrons ◽  
Rapid Loss ◽  
Emic Waves

scholarly journals Trapping and amplification of unguided mode EMIC waves in the radiation belt

2021 ◽  
Author(s):  
Geng Wang ◽  
Zhonglei Gao ◽  
Mingyu Wu ◽  
Guoqiang Wang ◽  
Sudong Xiao ◽  
...  
Keyword(s):  
Radiation Belt ◽  
Abundance Ratio ◽  
Relativistic Electrons ◽  
Scattering Loss ◽  
Propagation Behavior ◽  
Guided Mode ◽  
Waves Propagation ◽  
Spatial Locations ◽  
First Time ◽  
Emic Waves

Abstract Electromagnetic ion cyclotron (EMIC) waves can cause the scattering loss of the relativistic electrons in the earth's radiation belt. They can be classified into the guided mode and the unguided mode, according to waves propagation behavior. The guided mode waves have been widely investigated in the radiation belt, but the observation of the unguided mode waves have not been expected. Based on the observations of Van Allen Probes, we demonstrate for the first time the existence of the intense unguided mode EMIC waves. The reflection interface formed by the spatial locations of local helium cutoff frequencies can be nearly parallel to the equatorial plane when the proton abundance ratio decreases sharply with L-shell. This structure combined with the anisotropic hot protons can lead to the trapping and significant amplification of the unguided mode waves. These results may help to understand the nature of EMIC waves in the radiation belt.

Interactions between H+band EMIC waves and radiation belt relativistic electrons: Comparisons of test particle simulations with quasi-linear calculations

2019 ◽  
Vol 26 (3) ◽  
pp. 032901 ◽  
Author(s):  
Song Fu ◽  
Binbin Ni ◽  
Xin Tao ◽  
Yasong Ge ◽  
Jiang Liu ◽  
...  
Keyword(s):  
Test Particle ◽  
Radiation Belt ◽  
Relativistic Electrons ◽  
Particle Simulations ◽  
Emic Waves

Combined scattering loss of radiation belt relativistic electrons by simultaneous three-band EMIC waves: A case study

2016 ◽  
Vol 121 (5) ◽  
pp. 4446-4451 ◽  
Author(s):  
Fengming He ◽  
Xing Cao ◽  
Binbin Ni ◽  
Zheng Xiang ◽  
Chen Zhou ◽  
...  
Keyword(s):  
Radiation Belt ◽  
Relativistic Electrons ◽  
Scattering Loss ◽  
Emic Waves

Statistical EMIC diffusion models calculated by averaging observation specific diffusion coefficients

2021 ◽  
Author(s):  
Johnathan Ross ◽  
Sarah Glauert ◽  
Richard Horne ◽  
Nigel Meredith ◽  
Clare Watt
Keyword(s):  
Diffusion Coefficients ◽  
Radiation Belt ◽  
Diffusion Models ◽  
Relativistic Electrons ◽  
Particle Interactions ◽  
Resonant Wave ◽  
Van Allen Probes ◽  
Through Diffusion ◽  
Wave Particle Interactions ◽  
Emic Waves

<p>Electromagnetic ion cyclotron (EMIC) waves play an important role in relativistic electron losses in the radiation belts through diffusion via resonant wave-particle interactions. We present a new statistical model of electron diffusion by EMIC waves calculated, using Van Allen Probe observations, by averaging observation specific diffusion coefficients. The resulting diffusion coefficients therefore capture a wider range of wave-particle interactions than previous average models which are calculated using average observations. These calculations, and their role in radiation belt simulations, are then compared against existing diffusion models. The new diffusion coefficients are found to significantly improve the agreement between the calculated decay of relativistic electrons and Van Allen Probes data.</p><p> </p>

Nonlinear Interactions Between Relativistic Electrons and EMIC Waves in Magnetospheric Warm Plasma Environments

2020 ◽  
Vol 125 (12) ◽  
Author(s):  
Jiang Yu ◽  
L. Y. Li ◽  
Jun Cui ◽  
J. B. Cao ◽  
Jing Wang ◽  
...  
Keyword(s):  
Relativistic Electrons ◽  
Nonlinear Interactions ◽  
Warm Plasma ◽  
Emic Waves

Radial diffusion coefficients database in the frame of SafeSpace project

2021 ◽  
Author(s):  
Christos Katsavrias ◽  
Ioannis A. Daglis ◽  
Afroditi Nasi ◽  
Constantinos Papadimitriou ◽  
Marina Georgiou
Keyword(s):  
Diffusion Coefficients ◽  
Radiation Belt ◽  
Field Measurements ◽  
Radial Diffusion ◽  
Relativistic Electrons ◽  
Outer Radiation Belt ◽  
Horizon 2020 ◽  
Research And Innovation ◽  
The Difference ◽  
Cycle 24

<p>Radial diffusion has been established as one of the most important mechanisms contributing the acceleration and loss of relativistic electrons in the outer radiation belt. Over the past few years efforts have been devoted to provide empirical relationships of radial diffusion coefficients (D<sub>LL</sub>) for radiation belt simulations yet several studies have suggested that the difference between the various models can be orders of magnitude different at high levels of geomagnetic activity as the observed D<sub>LL</sub> have been shown to be highly event-specific. In the frame of SafeSpace project we have used 12 years (2009 – 2020) of multi-point magnetic and electric field measurements from THEMIS A, D and E satellites to create a database of calculated D<sub>LL</sub>. In this work we present the first statistics on the evolution of D<sub>LL </sub>during the various phases of Solar cycle 24 with respect to the various solar wind parameters and geomagnetic indices.</p><p>This work has received funding from the European Union's Horizon 2020 research and innovation programme “SafeSpace” under grant agreement No 870437.</p>

On the effect of ULF waves on the outer radiation belt during geomagnetic storms

2021 ◽  
Author(s):  
Christopher Lara ◽  
Pablo S. Moya ◽  
Victor Pinto ◽  
Javier Silva ◽  
Beatriz Zenteno
Keyword(s):  
Relativistic Electron ◽  
Radiation Belt ◽  
Geomagnetic Storms ◽  
Cumulative Effect ◽  
Radiation Belts ◽  
Ulf Waves ◽  
Relativistic Electrons ◽  
Relative Role ◽  
Outer Radiation Belt ◽  
Ulf Wave

<p>The inner magnetosphere is a very important region to study, as with satellite-based communications increasing day after day, possible disruptions are especially relevant due to the possible consequences in our daily life. It is becoming very important to know how the radiation belts behave, especially during strong geomagnetic activity. The radiation belts response to geomagnetic storms and solar wind conditions is still not fully understood, as relativistic electron fluxes in the outer radiation belt can be depleted, enhanced or not affected following intense activity. Different studies show how these results vary in the face of different events. As one of the main mechanisms affecting the dynamics of the radiation belt are wave-particle interactions between relativistic electrons and ULF waves. In this work we perform a statistical study of the relationship between ULF wave power and relativistic electron fluxes in the outer radiation belt during several geomagnetic storms, by using magnetic field and particle fluxes data measured by the Van Allen Probes between 2012 and 2017. We evaluate the correlation between the changes in flux and the cumulative effect of ULF wave activity during the main and recovery phases of the storms for different position in the outer radiation belt and energy channels. Our results show that there is a good correlation between the presence of ULF waves and the changes in flux during the recovery phase of the storm and that correlations vary as a function of energy. Also, we can see in detail how the ULF power change for the electron flux at different L-shell We expect these results to be relevant for the understanding of the relative role of ULF waves in the enhancements and depletions of energetic electrons in the radiation belts for condition described.</p>

scholarly journals PreMevE Update: Forecasting Ultra‐relativistic Electrons inside Earth’s Outer Radiation Belt

Space Weather ◽  
2021 ◽  
Author(s):  
Saurabh Sinha ◽  
Yue Chen ◽  
Youzuo Lin ◽  
Rafael Pires de Lima
Keyword(s):  
Radiation Belt ◽  
Relativistic Electrons ◽  
Outer Radiation Belt
Sign in / Sign up

Export Citation Format

Share Document