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1999
Tikhonchuk, V. T., Voronkov, I., Samson, J. C., Rankin, Robert
A model is presented that describes the excitation of density perturbations and parallel electric fields by standing shear Alfven waves on dipole fields in Earth's magnetosphere. The model includes the effects of electron inertia and gyro-kinetic dispersion, accounting for field-aligned...
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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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1994
Samson, J. C., Rankin, Robert, Wei, C. Q., Frycz, P.
A three-dimensional compressible resistive magnetohydrodynamic simulation code, with inclusion of the fully generalized Ohm's law, has been developed to study the nonlinear evolution of field line resonances in Earth's magnetosphere. A simple Cartesian box model of an inhomogeneous plasma with...
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1997
Samson, J. C., Rankin, Robert, Voronkov, I., Tikhonchuk, V. T.
The effect of the ponderomotive force (PF) on the temporal evolution of shear Alfven field line resonances (FLRs) is considered for a magnetic dipole geometry appropriate to the Earth's magnetosphere. We derive a set of equations which describes the coupling of shear Alfven and slow mode waves...
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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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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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1993
Frycz, P., Samson, J. C., Rankin, Robert
Using a compressible, three-dimensional resistive monohydrodynamic (MHD) computer simulation code, we examine the evolution of standing wave field line resonances (FLRs) in the nightside of the Earth's magnetosphere. The MHD code that is used allows for a full nonlinear description and enables us...
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1993
Frycz, P., Samson, J. C., Rankin, Robert, Harrold, B. G.
Magnetohydrodynamic, field line resonances in the Earth's magnetosphere can have very large velocity shears and field-aligned currents. Auroral radar measurements of high-latitude resonances indicate that the velocities associated with the resonances in the E and F regions am often substantially...