Abstract
A one-dimensional kinetic model is constructed to simulate the electron acceleration by inertial Alfven waves. The electrons are divided into cold and hot electrons and treated separately. Cold components are described by the fluid equation and hot ones by the Vlasov equation, both carrying field-aligned currents. Intense variation of Alfven speed has been introduced by inclusion of cold electrons. The model results show that the exponential decrease of the plasma density plays a key role, which leads to the sharp gradient of both Alfven velocity and electron inertial length. When Alfven waves encounter this sharp gradient at lower altitudes, the electrons accelerated by the waves become super-Alfvenic, and the width of burst structures becomes much wider than the electron inertial length. Consequently, the background electrons carry the oppositely field-aligned current due to plasma oscillation. It is demonstrated that the current carried by the electrons exceeding the wavefront is balanced by the reverse current carried by background electrons. This mechanism can be used to reasonably explain observations of the electron bursts accompanied by little net field-aligned current. Furthermore, our simulation indicates another type of Alfven wave reflection due to mirror force and wave-particle interaction. Key Points Kinetic model which separates the electrons into cold and hot parts Explain the electron bursts accompanied by little net field-aligned current Another type of Alfven wave reflection due to wave-particle interaction
| Original language | English |
|---|---|
| Pages (from-to) | 2903-2910 |
| Number of pages | 8 |
| Journal | Journal of Geophysical Research: Space Physics |
| Volume | 118 |
| Issue number | 6 |
| DOIs | |
| Publication status | Published - Jan 1 2013 |
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- Aquatic Science
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- Geochemistry and Petrology
- Earth-Surface Processes
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Cite this
Coupling of electrons and inertial Alfven waves in the topside ionosphere. / Shi, Run; Liu, Huixin; Yoshikawa, Akimasa; Zhang, Beichen; Ni, Binbin.
In: Journal of Geophysical Research: Space Physics, Vol. 118, No. 6, 01.01.2013, p. 2903-2910.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Coupling of electrons and inertial Alfven waves in the topside ionosphere
AU - Shi, Run
AU - Liu, Huixin
AU - Yoshikawa, Akimasa
AU - Zhang, Beichen
AU - Ni, Binbin
PY - 2013/1/1
Y1 - 2013/1/1
N2 - A one-dimensional kinetic model is constructed to simulate the electron acceleration by inertial Alfven waves. The electrons are divided into cold and hot electrons and treated separately. Cold components are described by the fluid equation and hot ones by the Vlasov equation, both carrying field-aligned currents. Intense variation of Alfven speed has been introduced by inclusion of cold electrons. The model results show that the exponential decrease of the plasma density plays a key role, which leads to the sharp gradient of both Alfven velocity and electron inertial length. When Alfven waves encounter this sharp gradient at lower altitudes, the electrons accelerated by the waves become super-Alfvenic, and the width of burst structures becomes much wider than the electron inertial length. Consequently, the background electrons carry the oppositely field-aligned current due to plasma oscillation. It is demonstrated that the current carried by the electrons exceeding the wavefront is balanced by the reverse current carried by background electrons. This mechanism can be used to reasonably explain observations of the electron bursts accompanied by little net field-aligned current. Furthermore, our simulation indicates another type of Alfven wave reflection due to mirror force and wave-particle interaction. Key Points Kinetic model which separates the electrons into cold and hot parts Explain the electron bursts accompanied by little net field-aligned current Another type of Alfven wave reflection due to wave-particle interaction
AB - A one-dimensional kinetic model is constructed to simulate the electron acceleration by inertial Alfven waves. The electrons are divided into cold and hot electrons and treated separately. Cold components are described by the fluid equation and hot ones by the Vlasov equation, both carrying field-aligned currents. Intense variation of Alfven speed has been introduced by inclusion of cold electrons. The model results show that the exponential decrease of the plasma density plays a key role, which leads to the sharp gradient of both Alfven velocity and electron inertial length. When Alfven waves encounter this sharp gradient at lower altitudes, the electrons accelerated by the waves become super-Alfvenic, and the width of burst structures becomes much wider than the electron inertial length. Consequently, the background electrons carry the oppositely field-aligned current due to plasma oscillation. It is demonstrated that the current carried by the electrons exceeding the wavefront is balanced by the reverse current carried by background electrons. This mechanism can be used to reasonably explain observations of the electron bursts accompanied by little net field-aligned current. Furthermore, our simulation indicates another type of Alfven wave reflection due to mirror force and wave-particle interaction. Key Points Kinetic model which separates the electrons into cold and hot parts Explain the electron bursts accompanied by little net field-aligned current Another type of Alfven wave reflection due to wave-particle interaction
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U2 - 10.1002/jgra.50355
DO - 10.1002/jgra.50355
M3 - Article
AN - SCOPUS:84883041879
VL - 118
SP - 2903
EP - 2910
JO - Journal of Geophysical Research
JF - Journal of Geophysical Research
SN - 0148-0227
IS - 6
ER -