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[en] By means of analysis of the latitude distrebutions of Ps6 amplitude and appearance frequency it is shown that the ionospheric projection of the most probable region of their generation is located in 4-6 deg to North relative to the projection of the inner edge of the plasma sheet
[en] The compact-arc model with a current sheet can describe the spectral line profiles of Severnyi moustache structures observed in the optical range. Plasma streaming from the current sheet is responsible for the extended wings in the moustache profiles. The radiation of the sheet itself will probably manifest itself as a strip of continuous emission
[en] A magnetized sheet plasma ion source was developed for steady state high density plasma with strong density and high temperature gradients. This feature provides efficient formation of negative hydrogen (H-) ions over a wide beam extraction area through the electron volume process. A hexapole confinement at the cathode, addition of argon and magnesium seeding led to the increase of H- yield. The device configuration is suitable for plasma based materials processing namely, synthesis of TiN, SiH, SnO2, and the formation of advanced MAX phase materials Ti2AlC, Ti2CdC and NbAlC. (author)
[en] Complete text of publication follows. The role of entropy conservation and loss in plasma transport in the inner plasma sheet is discussed on the basis of MHD theory and simulations. Entropy loss, for instance by ejection of plasmoids, is essential in the earthward transport of flux tubes (bubbles, bursty bulk flows). Entropy loss also changes the tail stability properties and may render ballooning modes unstable and thus contribute to cross-tail variability. We illustrate these effects through results from theory and simulations.
[en] Between 2004 July 5 and July 7, two intriguing fast coronal mass ejection (CME)-streamer interaction events were recorded by the Large Angle and Spectrometric Coronagraph. At the beginning of the events, the streamer was pushed aside from its equilibrium position upon the impact of the rapidly outgoing and expanding ejecta; then, the streamer structure, mainly the bright streamer belt, exhibited elegant large-scale sinusoidal wavelike motions. The motions were apparently driven by the restoring magnetic forces resulting from the CME impingement, suggestive of magnetohydrodynamic kink mode propagating outward along the plasma sheet of the streamer. The mode is supported collectively by the streamer-plasma sheet structure and is therefore named 'streamer wave' in the present study. With the white light coronagraph data, we show that the streamer wave has a period of about 1 hr, a wavelength varying from 2 to 4 solar radii, an amplitude of about a few tens of solar radii, and a propagating phase speed in the range 300-500 km s-1. We also find that there is a tendency for the phase speed to decline with increasing heliocentric distance. These observations provide good examples of large-scale wave phenomena carried by coronal structures and have significance in developing seismological techniques for diagnosing plasma and magnetic parameters in the outer corona.
[en] Results from modeling ion distribution functions in a two-dimensional reduction of the Tsyganenko magnetic field model have enabled the authors to calculate the full ion pressure tensor inside the model magnetotail. A thin current sheet is formed in the distant tail and the pressure tensor within this sheet has significant off-diagonal terms. These terms resulting from quasiadiabatic ion trajectories create azimuthally asymmetric distribution functions which are capable of maintaining stress-balance. Outside the current sheet the off-diagonal terms disappear and moderate anisotropy builds up with P perpendicular/P parallel ∼ 0.8. Closer to the Earth rapid isotropization of the distribution occurs
[en] Complete text of publication follows. The first tail season of the THEMIS mission provides rare opportunities for observations of flux rope and travelling compression region (TCR) development and transport at multiple points in the Earth's magnetotail. The two most distant THEMIS spacecraft are used to observe, for the first time, flux ropes at one location embedded in plasma sheet flows producing TCRs at another satellite. The unique alignment of the THEMIS probes enables a comparison of the flux rope speed determined from inter-spacecraft timing with in situ plasma measurements. Flux rope orientation, dimensions and temporal evolution inferred from these multi-point measurements will be presented.