Visualization of ion cyclotron wave and particle interactions in the inner magnetosphere via THEMIS-ASI observations

2012 ◽  
Vol 117 (A10) ◽  
pp. n/a-n/a ◽  
Author(s):  
K. Sakaguchi ◽  
Y. Miyoshi ◽  
E. Spanswick ◽  
E. Donovan ◽  
I. R. Mann ◽  
...  
Keyword(s):  
Particle Interactions ◽  
Inner Magnetosphere ◽  
Ion Cyclotron

scholarly journals Ion Heating by Electromagnetic Ion Cyclotron Waves and Magnetosonic Waves in the Earth's Inner Magnetosphere

2019 ◽  
Vol 46 (12) ◽  
pp. 6258-6267 ◽  
Author(s):  
Q. Ma ◽  
W. Li ◽  
C. Yue ◽  
R. M. Thorne ◽  
J. Bortnik ◽  
...  
Keyword(s):  
Ion Heating ◽  
Inner Magnetosphere ◽  
Ion Cyclotron Waves ◽  
Ion Cyclotron ◽  
Electromagnetic Ion Cyclotron Waves

Wave-particle interactions near ΩHe+observed on GEOS 1 and 2 1. Propagation of ion cyclotron waves in He+-rich plasma

1981 ◽  
Vol 86 (A8) ◽  
pp. 6755 ◽  
Author(s):  
D. T. Young ◽  
S. Perraut ◽  
A. Roux ◽  
C. de Villedary ◽  
R. Gendrin ◽  
...  
Keyword(s):  
Particle Interactions ◽  
Ion Cyclotron Waves ◽  
Ion Cyclotron ◽  
Wave Particle Interactions

scholarly journals Interhemispheric asymmetries in the occurrence of magnetically conjugate sub-auroral polarisation streams

2005 ◽  
Vol 23 (4) ◽  
pp. 1371-1390 ◽  
Author(s):  
M. L. Parkinson ◽  
M. Pinnock ◽  
J. A. Wild ◽  
M. Lester ◽  
T. K. Yeoman ◽  
...  
Keyword(s):  
Electric Field ◽  
Auroral Oval ◽  
Particle Interactions ◽  
Magnetospheric Substorms ◽  
Polarisation Field ◽  
Energetic Ions ◽  
Inner Magnetosphere ◽  
Flux Tubes ◽  
Ion Drift ◽  
Magnetic Flux Tubes

Abstract. Earthward injections of energetic ions and electrons mark the onset of magnetospheric substorms. In the inner magnetosphere (L4), the energetic ions drift westward and the electrons eastward, thereby enhancing the equatorial ring current. Wave-particle interactions can accelerate these particles to radiation belt energies. The ions are injected slightly closer to Earth in the pre-midnight sector, leading to the formation of a radial polarisation field in the inner magnetosphere. This maps to a poleward electric field just equatorward of the auroral oval in the ionosphere. The poleward electric field is subsequently amplified by ionospheric feedback, thereby producing auroral westward flow channels (AWFCs). In terms of electric field strength, AWFCs are the strongest manifestation of substorms in the ionosphere. Because geomagnetic flux tubes are essentially equi-potentials, similar AWFC signatures should be observed simultaneously in the Northern and Southern Hemispheres. Here we present magnetically conjugate SuperDARN radar observations of AWFC activity observed in the pre-midnight sector during two substorm intervals including multiple onsets during the evening of 30 November 2002. The Northern Hemisphere observations were made with the Japanese radar located at King Salmon, Alaska (57, and the Southern Hemisphere observations with the Tasman International Geospace Environment Radar (TIGER) located at Bruny Island, Tasmania (55. LANL geosynchronous satellite observations of energetic ion and electron fluxes monitored the effects of substorms in the inner magnetosphere (L6). The radar-observed AWFC activity was coincident with activity observed at geosynchronous orbit, as well as westward current surges in the ionosphere observed using ground-based magnetometers. The location of AWFCs with respect to the auroral oval was inferred from FUV auroral images recorded on board the IMAGE spacecraft. DMSP SSIES ion drift measurements confirmed the presence of AWFCs equatorward of the auroral oval. Systematic asymmetries in the interhemispheric signatures of the AWFCs probably arose because the magnetic flux tubes were distorted at L shells passing close to the substorm dipolarisation region. Transient asymmetries were attributed to the development of nearby field-aligned potential drops and currents.

scholarly journals Ring Current Proton Dynamics Driven by Wave-Particle Interactions During a Nonstorm Period

2021 ◽  
pp. 98-104
Author(s):  
Sergei V. Smolin
Keyword(s):  
Pitch Angle ◽  
Ring Current ◽  
Activity Index ◽  
Proton Flux ◽  
Angle Distribution ◽  
Particle Interactions ◽  
Pitch Angle Distribution ◽  
Ion Cyclotron ◽  
Wave Particle Interactions ◽  
Emic Waves

Modeling of pitch angle scattering of ring current protons at interaction with electromagnetic ion cyclotron waves during a nonstorm period was considered very seldom. Therefore it is used correlated observation of enhanced electromagnetic ion cyclotron (EMIC) waves and dynamic evolution of ring current proton flux collected by Cluster satellite near the location L = 4.5 during March 26–27, 2003, a nonstorm period (Dst > –10 nT). Energetic (5–30 keV) proton fluxes are found to drop rapidly (e.g., a half hour) at lower pitch angles, corresponding to intensified EMIC wave activities. As mathematical model is used the non-stationary one-dimensional pitch angle diffusion equation which allows to compute numerically density of phase space or pitch angle distribution of the charged particles in the Earth’s magnetosphere. The model depends on time t, a local pitch angle and several parameters (the mass of a particle, the energy, the McIlwain parameter, the magnetic local time or geomagnetic eastern longitude, the geomagnetic activity index, parameter of the charged particle pitch angle distribution taken for the 90 degrees pitch angle at t = 0, the lifetime due to wave–particle interactions). This model allows numerically to estimate also for different geophysical conditions a lifetime due to wave–particle interactions. It is shown, that EMIC waves can yield decrements in proton flux within 30 minutes, consistent with the observational data. The good consent is received. Comparison of results on full model for the pitch angle range from 0 up to 180 degrees and on the model for the 90 degrees pitch angle is lead. For a perpendicular differential flux of the Earth’s ring current protons very good consent with the maximal relative error approximately 3.23 % is received

scholarly journals Energy Exchange Between Electromagnetic Ion Cyclotron (EMIC) Waves and Thermal Plasma: From Theory to Observations

2021 ◽  
Vol 8 ◽  
Author(s):  
M. E. Usanova
Keyword(s):  
Thermal Plasma ◽  
Ring Current ◽  
Plasma Heating ◽  
Particle Interactions ◽  
Ion Heating ◽  
Thermal Electron ◽  
Plasma Species ◽  
Ion Cyclotron ◽  
Radiation Belt Electrons ◽  
Emic Waves

The cold plasmaspheric plasma, the ring current and the radiation belts constitute three important populations of the inner magnetosphere. The overlap region between these populations gives rise to wave-particle interactions between different plasma species and wave modes observed in the magnetosphere, in particular, electromagnetic ion cyclotron (EMIC) waves. These waves can resonantly interact with multiple particle species, being an important loss process for both ring current ions and radiation belt electrons, as well as a cold plasma heating mechanism. This mini-review will focus on the interaction between EMIC waves and cold and thermal plasma, specifically the role of EMIC waves in cold and thermal electron and ion heating. It will discuss early theoretical results in conjunction with numerical modelling and recent satellite observations, and address outstanding problems and controversies in this field.

scholarly journals Plasma Waves in the Inner Magnetosphere

2021 ◽  
pp. 85-119
Author(s):  
Hannu E. J. Koskinen ◽  
Emilia K. J. Kilpua
Keyword(s):  
Radiation Belt ◽  
Low Frequency ◽  
Plasma Waves ◽  
Mhd Waves ◽  
Particle Interactions ◽  
Inner Magnetosphere ◽  
Very Low Frequency ◽  
Link Type ◽  
Wave Modes

AbstractUnderstanding the role of plasma waves, extending from magnetohydrodynamic (MHD) waves at ultra-low-frequency (ULF) oscillations in the millihertz range to very-low-frequency (VLF) whistler-mode emissions at frequencies of a few kHz, is necessary in studies of sources and losses of radiation belt particles. In order to make this theoretically heavy part of the book accessible to a reader, who is not familiar with wave–particle interactions, we have divided the treatise into three chapters. In the present chapter we introduce the most important wave modes that are critical to the dynamics of radiation belts. The drivers of these waves are discussed in Chap. 10.1007/978-3-030-82167-8_5 and the roles of the wave modes as sources and losses of radiation belt particles are dealt with in Chap. 10.1007/978-3-030-82167-8_6.

scholarly journals Properties of A Supercritical Quasi-Perpendicular Interplanetary Shock Propagating in Super-Alfvénic Solar Wind: from MHD to Kinetic Scales

2021 ◽  
Author(s):  
Mingzhe Liu ◽  
Zhongwei Yang ◽  
Ying D. Liu ◽  
Bertrand Lembege ◽  
Karine Issautier ◽  
...  
Keyword(s):  
Solar Wind ◽  
Energy Dissipation ◽  
Interplanetary Shock ◽  
Particle Interactions ◽  
Temperature Anisotropy ◽  
Ion Cyclotron Waves ◽  
Proton Temperature ◽  
Ion Cyclotron ◽  
Mirror Mode

<p>We investigate the properties of an interplanetary shock (M<sub>A</sub>=3.0, θ<sub>Bn</sub>=80°) propagating in Super-Alfvénic solar wind observed on September 12<sup>th,</sup> 1999 with in situ Wind/MFI and Wind/3DP observations. Key results are obtained concerning the possible energy dissipation mechanisms across the shock and how the shock modifies the ambient solar wind at MHD and kinetic scales:  (1) Waves observed in the far upstream of the shock are incompressional and mostly shear Alfvén waves.  (2) In the downstream, the shocked solar wind shows both Alfvénic and mirror-mode features due to the coupling between the Alfvén waves and ion mirror-mode waves.  (3) Specularly reflected gyrating ions, whistler waves, and ion cyclotron waves are observed around the shock ramp, indicating that the shock may rely on both particle reflection and wave-particle interactions for energy dissipation.  (4) Both ion cyclotron and mirror mode instabilities may be excited in the downstream of the shock since the proton temperature anisotropy touches their thresholds due to the enhanced proton temperature anisotropy.  (5) Whistler heat flux instabilities excited around the shock give free energy for the whistler precursors, which help explain the isotropic electron number and energy flux together with the normal betatron acceleration of electrons across the shock.  (6) The shock may be somehow connected to the electron foreshock region of the Earth’s bow shock, since Bx > 0, By < 0, and the electron flux varies only when the electron pitch angles are less than PA = 90°, which should be further investigated. Furthermore, the interaction between Alfvén waves and the shock and how the shock modifies the properties of the Alfvén waves are also discussed.</p>

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