scholarly journals Correlation of Alfvén wave Poynting flux in the plasma sheet at 4–7REwith ionospheric electron energy flux

2002 ◽  
Vol 107 (A7) ◽  
Author(s):  
A. Keiling
Keyword(s):  
Electron Energy ◽  
Energy Flux ◽  
Plasma Sheet ◽  
Alfven Wave ◽  
Poynting Flux

scholarly journals Compressional wave events in the dawn plasma sheet observed by Interball-1

1999 ◽  
Vol 17 (9) ◽  
pp. 1145-1154 ◽  
Author(s):  
O. Verkhoglyadova ◽  
A. Agapitov ◽  
A. Andrushchenko ◽  
V. Ivchenko ◽  
S. Romanov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Time Series ◽  
Field Line ◽  
Plasma Sheet ◽  
Inhomogeneous Plasma ◽  
Partial Solution ◽  
Alfven Wave ◽  
Data Set ◽  
Background Magnetic Field ◽  
Phase Variations

Abstract. Compressional waves with periods greater than 2 min (about 10-30 min) at low geomagnetic latitudes, namely compressional Pc5 waves, are studied. The data set obtained with magnetometer MIF-M and plasma analyzer instrument CORALL on board the Interball-1 are analyzed. Measurements performed in October 1995 and October 1996 in the dawn plasma sheet at -30 RE ≤ XGSM and |ZGSM| ≤ 10 RE are considered. Anti-phase variations of magnetic field and ion plasma pressures are analyzed by searching for morphological similarities in the two time series. It is found that longitudinal and transverse magnetic field variations with respect to the background magnetic field are of the same order of magnitude. Plasma velocities are processed for each time period of the local dissimilarity in the pressure time series. Velocity disturbances occur mainly transversely to the local field line. The data reveal the rotation of the velocity vector. Because of the field line curvature, there is no fixed position of the rotational plane in the space. These vortices are localized in the regions of anti-phase variations of the magnetic field and plasma pressures, and the vortical flows are associated with the compressional Pc5 wave process. A theoretical model is proposed to explain the main features of the nonlinear wave processes. Our main goal is to study coupling of drift Alfven wave and magnetosonic wave in a warm inhomogeneous plasma. A vortex is the partial solution of the set of the equations when the compression is neglected. A compression effect gives rise to a nonlinear soliton-like solution.Key words. Magnetosphere physics (magnetotail) · Space plasma physics (kinetic and MHD theory; non-linear phenomena)

scholarly journals Precipitating Electron Energy Flux and Characteristic Energies in Jupiter's Main Auroral Region as Measured by Juno/JEDI

2018 ◽  
Vol 123 (9) ◽  
pp. 7554-7567 ◽  
Author(s):  
G. Clark ◽  
C. Tao ◽  
B. H. Mauk ◽  
J. Nichols ◽  
J. Saur ◽  
...  
Keyword(s):  
Electron Energy ◽  
Energy Flux ◽  
Auroral Region

Electron energy flux control using dual power in side-type inductively coupled plasma

2011 ◽  
Vol 18 (7) ◽  
pp. 073507 ◽  
Author(s):  
Jin-Young Bang ◽  
Jin-Yong Kim ◽  
Chin-Wook Chung
Keyword(s):  
Electron Energy ◽  
Energy Flux ◽  
Inductively Coupled Plasma ◽  
Flux Control ◽  
Inductively Coupled ◽  
Dual Power

scholarly journals Does the Magnetodynamic Model for the Formation of AGN Jets Survive New Findings of High-energy Phenomena near the Central Objects?

2000 ◽  
Vol 195 ◽  
pp. 473-481
Author(s):  
Y. Uchida
Keyword(s):  
Lorentz Factor ◽  
High Energy ◽  
Major Effect ◽  
Alfven Wave ◽  
Poynting Flux ◽  
Central Engine ◽  
New Findings ◽  
Wave Trains ◽  
Kink Instability ◽  
Jet Structure

Here, we argue that, despite all-new findings of phenomena with very large Lorentz factors, the importance of the magnetodynamic process accelerating and collimating AGN jets should not be affected because there exists evidence in the features of the jets and tails at large distances indicating that the wiggles of the jet structure are likely to be due to a magnetic, helical kink instability. These systematic features require too much energy and coherence of the driving process to be produced locally and axe most naturally produced by a magnetic effect coming from the powerful central engine. This indicates that the major effect producing the jets, and the lobes with hotspots at the tips of the jets, is likely to be the Poynting flux carried by torsional Alfvén wave trains plus the re-accelerated high-energy particles in them. The very large Lorentz-factor phenomena should not hinder the transfer of these magnetic effects and are likely to be byproducts of the basic magnetodynamic process, and not the reverse.

scholarly journals High-latitude poynting flux from combined Iridium and SuperDARN data

2004 ◽  
Vol 22 (8) ◽  
pp. 2861-2875 ◽  
Author(s):  
C. L. Waters ◽  
B. J. Anderson ◽  
R. A. Greenwald ◽  
R. J. Barnes ◽  
J. M. Ruohoniemi
Keyword(s):  
Electric Fields ◽  
Energy Flux ◽  
High Latitude ◽  
Electromagnetic Energy ◽  
Total Power ◽  
Data Sets ◽  
Poynting Flux ◽  
Magnetic Perturbations ◽  
Magnetometer Data ◽  
A New Technique

Abstract. Field-aligned currents convey stress between the magnetosphere and ionosphere, and the associated low altitude magnetic and electric fields reflect the flow of electromagnetic energy to the polar ionosphere. We introduce a new technique to measure the global distribution of high latitude Poynting flux, S||, by combining electric field estimates from the Super Dual Auroral Radar Network (SuperDARN) with magnetic perturbations derived using magnetometer data from the Iridium satellite constellation. Spherical harmonic methods are used to merge the data sets and calculate S|| for any magnetic local time (MLT) from the pole to 60° magnetic latitude (MLAT). The effective spatial resolutions are 2° MLAT, 2h MLT, and the time resolution is about one hour due to the telemetry rate of the Iridium magnetometer data. The technique allows for the assessment of high-latitude net S|| and its spatial distribution on one hour time scales with two key advantages: (1) it yields the net S|| including the contribution of neutral winds; and (2) the results are obtained without recourse to estimates of ionosphere conductivity. We present two examples, 23 November 1999, 14:00-15:00 UT, and 11 March 2000, 16:00-17:00 UT, to test the accuracy of the technique and to illustrate the distributions of S|| that it gives. Comparisons with in-situ S|| estimates from DMSP satellites show agreement to a few mW/m2 and in the locations of S|| enhancements to within the technique's resolution. The total electromagnetic energy flux was 50GW for these events. At auroral latitudes, S|| tends to maximize in the morning and afternoon in regions less than 5° in MLAT by two hours in MLT having S||=10 to 20mW/m2 and total power up to 10GW. The power poleward of the Region 1 currents is about one-third of the total power, indicating significant energy flux over the polar cap.

The transformation of magnetoacoustic waves into Alfvén waves inside the magnetosphere

1994 ◽  
Vol 12 (10/11) ◽  
pp. 1022-1026 ◽  
Author(s):  
A. E. Kozlovsky ◽  
V. V. Safargaleev ◽  
W. B. Lyatsky
Keyword(s):  
Solar Wind ◽  
Plasma Sheet ◽  
Alfven Waves ◽  
Alfven Wave ◽  
Alfvén Waves ◽  
Magnetoacoustic Wave ◽  
Magnetoacoustic Waves

Abstract. A mechanism for the transformation of a magnetoacoustic wave into an Alfvén wave is proposed. During the compression of the magnetosphere by the solar wind the inner edge of the plasma sheet and the contours of B=const move in different ways. In the case of asymmetrical compression, the contours of B=const will cross the inner edge of the plasma sheet. To close the drift currents - that flow in the plasma sheet along the contours of B=const - the appearance of the field-aligned currents is necessary. This appearance corresponds to the generation of the Alfvén wave.

Temporal Alfvén wave echoes in an inhomogeneous plasma

1984 ◽  
Vol 31 (3) ◽  
pp. 395-414 ◽  
Author(s):  
I. C. Rae
Keyword(s):  
Surface Wave ◽  
Plasma Sheet ◽  
Inhomogeneous Plasma ◽  
Nonlinear Effects ◽  
Alfven Wave ◽  
Surface Phase ◽  
Initial Pulse ◽  
External Current ◽  
First Order ◽  
Resonance Surface

If an external current pulse is applied to a diffuse plasma sheet pinch, surface wave modes are generated, which decay by collisionless damping, leaving only oscillations of the Alfvén continuum along the Alfvén resonance surface. The transverse perturbations within this surface phase-mix to zero. It is shown that perturbations induced by an initial pulse are modulated by a (later applied) second pulse of different wavelength, to yield non-vanishing second-order transverse perturbations, even though the first-order transverse perturbations have phase-mixed to zero. This analysis shows the importance of nonlinear effects in the evolution of inhomogeneous magnetohydrodynamic motions.

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