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Skip to Search Results- 4Earths Magnetosphere
- 4Field Line Resonances
- 3Magnetic-Field
- 3Plasma
- 3Shear Alfven Waves
- 2Acceleration
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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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Finite element modeling of nonlinear dispersive field line resonances: Trapped shear Alfvén waves inside field‐aligned density structures
Download2003-01-01
Marchand, Richard, Rankin, Robert, Wanliss, J. , Tikhonchuk, V. T., Lu, J. Y.
Using a new two- dimensional nonlinear finite element model, we investigate the interaction of dispersive shear Alfven wave ( SAW) field line resonances ( FLRs) and ion acoustic waves in Earth's magnetosphere. We solve the full set of nonlinear reduced MHD equations self- consistently in...
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International Collaboration Within the United Nations Committee on the Peaceful Uses of Outer Space: Framework for International Space Weather Services (2018–2030)
Download2018-05-06
Mann, I. R., Di Pippo, S., Opgenoorth, H. J., Kuznetsova, M., Kendall, D. J.
Severe space weather is a global threat that requires a coordinated global response. In this Commentary, we review some previous successful actions supporting international coordination between member states in the United Nations (UN) context and make recommendations for a future approach. Member...
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Magnetospheric field‐line resonances: Ground‐based observations and modelingournal of Geophysical Research: Space Physics, 110(A10), [pp
Download2005
Mann, I. R., Kabin, Konstantin, Donovan, E. F., Lu, J. Y., Rankin, Robert, Rae, I. Jonathan, Marchand, Richard
We present theory and ground-based observations of field-line resonances (FLRs) excited in Earth's magnetosphere. Three FLR observations are reported, which correspond to large-scale standing shear Alfven wave (SAW) oscillations on nightside field lines extending from premidnight to close to...
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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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1998
Rankin, Robert, Tikhonchuk, V. T.
We describe nonlinear resonance absorption of compressional Alfven waves in a model magnetosphere. It is shown that the ponderomotive force of excited standing shear Alfven waves can lead to nonlinear saturation and spatial structuring of field line resonances and that in low-beta plasmas...
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On the Role of Last Closed Drift Shell Dynamics in Driving Fast Losses and Van Allen Radiation Belt Extinction
Download2018-04-20
Olifer, L., Mann, I. R., Morley, S. K., Ozeke, L. G., Choi, D.
We present observations of very fast radiation belt loss as resolved using high time resolution electron flux data from the constellation of Global Positioning System (GPS) satellites. The time scale of these losses is revealed to be as short as ∼0.5–2 hr during intense magnetic storms, with some...
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Precipitation and nonlinear effects in geomagnetic field line resonancesournal of Geophysical Research: Space Physics, 108(A4), [pp
Download2003
Tikhonchuk, V. T., Prakash, M., Rankin, Robert
The structure of auroral arcs sustained by field line resonances (FLRs) is determined using a model that describes the interplay between ionospheric feedback, nonlinear, and dispersive effects in a curvilinear geomagnetic topology. The model includes modulation of Pedersen conductance by hundreds...