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Skip to Search Results- 6Kelvin-Helmholtz Instability
- 5Auroral Arcs
- 4Field Line Resonances
- 2Alfven Waves
- 2Dynamics
- 2Electrons
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2009
Kabin, Konstantin, Liu, Wenlong, Ergun, Robert, Angelopoulos, Vassilis, Elkington, Scot R., Glassmeier, Karl-Heinz, Li, X., Sarris, T. E., Bonnell, John, Auster, Hans-Ulrich
The THEMIS five-probe constellation was launched in 17 February 2007 to study substorms; however its instrumentation and the alignment at distances <1RE among some of the THEMIS probes, particularly in the first period of its mission, provides unique opportunities to study ULF pulsations in the...
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2011
Elkington, Scot R., Degeling, Alex W., Rankin, Robert
The process of magnetospheric radiation belt electron transport driven by ULF waves is studied using a 2-D ideal MHD model for ULF waves in the equatorial plane including day/night asymmetry and a magnetopause boundary, and a test kinetic model for equatorially mirroring electrons. We find that...
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1997
Tikhonchuk, V. T., Voronkov, I., Frycz, P., Samson, J. C., Rankin, Robert
The nonlinear dynamics of a shear flow and its subsequent evolution in the equatorial plane of the inner plasma sheet is studied. A linear analysis of the ideal MHD equations reveals a hybrid vortex instability which appears because of the coupling of Kelvin-Helmholtz (KH) and Rayleigh-Taylor...
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Electrodynamics of magnetosphere‐ionosphere coupling and feedback on magnetospheric field line resonances
Download2007
Marchand, Richard, Lu, J. Y., Rankin, Robert, Solomon, Stanley C., Wang, Wenbin, Lei, J., Rae, I. Johnathan
We present a new dynamic model that describes coupling between standing inertial or ion-acoustic-gyroradius-scale shear Alfven waves, compressional modes, and auroral density disturbances. The model is applied to the excitation of field line resonances (FLRs) in dipolar and stretched geomagnetic...
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2016
Turkakin, Hava, Rankin, Robert, Mann, Ian R.
The emission of propagating MHD waves from the boundaries of flow channels that are unstable to the Kelvin-Helmholtz Instability (KHI) in magnetized plasma is investigated. The KHI and MHD wave emission are found to be two competing processes. It is shown that the fastest growing modes of the KHI...
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2014
Watt, Clare E. J., Hodgson, Cory R., Forsyth, Colin, Degeling, Alex W., Murphy, K. R., Rankin, Robert, Mann, Ian R., Rostoker, Gordon, Frey, Harald U., Rae, I. Johnathan
In this paper, we show that periodic auroral arc structures are seen at the location of one particular auroral substorm onset for the 15 min preceding onset, suggesting that field line resonances should be considered a strong candidate for triggering substorm onset. Irrespective of whether this...
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1994
Tikhonchuk, V. T., Frycz, P., Samson, J. C., Rankin, Robert
We present theory and numerical simulations of strong nonlinear effects in standing shear Alfven waves (SAWs) in the Earth's magnetosphere, which is modeled as a finite size box with straight magnetic lines and (partially) reflecting boundaries. In a low beta plasma it is shown that the...
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Shear Alfvén waves on stretched magnetic field lines near midnight in Earth's magnetosphere
Download2000
Tikhonchuk, Vladimir T., Rankin, Robert, Fenrich, Frances
The spectrum of toroidal standing shear Alfvén waves (SAWs) is derived for a stretched magnetic field line geometry that is approximated by the Tsyganenko 96 magnetic field model. The model is applied to field lines near the midnight meridional plane. It is demonstrated that the fundamental mode...
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1999
Tikhonchuk, V. T., Voronkov, I., Samson, J. C., Rankin, Robert
The three-dimensional, nonlinear evolution of a shear how (or Kelvin-Helmholtz (KH)) instability driven by a large-amplitude shear Alfven wave (SAW) in the Earth's magnetosphere is studied by using numerical solutions to the complete set of ideal magnetohydrodynamic equations. An initial setup is...
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Stability of Magnetohydrodynamic Shear Flow Boundaries: Kelvin-Helmholtz Instabilities and Emission of Magnetosonic Waves
DownloadSpring 2015
boundaries for the Kelvin-Helmholtz Instability (KHI) is investigated. We have focused our attention on the emission of magnetosonic waves from the Kelvin-Helmholtz (K-H) unstable shear flow boundaries of MHD plasmas. We have shown for the first time that the Kelvin-Helmholtz Instability is a...