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Alfvén modes in a two-species magnetoplasma with anisotropic perturbation pressure-fluid and kinetic calculations

Published online by Cambridge University Press:  01 August 2007

C. ALTMAN  and
K. SUCHY
C. ALTMAN
Affiliation:
Physics Department, Technion-Israel Institute of Technology, Haifa 32000, Israel
K. SUCHY
Affiliation:
Institute for Theoretical Physics, Universitätsstrasse 1, D-40225 Düsseldorf, Germany
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Abstract

The octic fluid dispersion equation, the kinetic Boltzmann–Vlasov equation and the MHD (scalar pressure) analysis, programmed for a two-species collisionless magnetoplasma in a form permitting direct comparison between them, have been applied to the study of the Alfvén modes in both low- and high-β plasmas. In the low-βregime all methods give essentially the same solutions for the isotropic fast magnetosonic and the field-guided shear Alfvén modes. The real part of the refractive index of the field-guided slow magnetosonic acoustic mode is almost identical in the fluid and kinetic analyses, but is 50% too high in the MHD analysis owing to neglect of the trace-free part of the pressure tensor which drives almost half of the acoustic energy flux. The strong damping of the acoustic mode in both low- and high-β plasmas is drastically reduced by increase of electron temperature, whereas a moderate increase in the perpendicular ion temperature is sufficient to eliminate shear Alfvén damping in high-β plasmas and even to produce wave growth, the effect being more pronounced the higher the plasma β. The fluid analysis shows the electromagnetic energy flux to be negligible in the acoustic mode, in which the acoustic flux is driven both by the trace-carrying and trace-free parts of the pressure tensor, but is usually the dominant component in the (fast) magnetosonic mode.

Type
Papers
Information
Journal of Plasma Physics , Volume 73 , Issue 4 , August 2007 , pp. 455 - 471
Copyright
Copyright © Cambridge University Press 2006

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References

[1]Suchy, K. and Altman, C. 2003 Wave modes in a magnetoplasma with anisotropic perturbation pressure. J. Plasma Phys. 69, 69–87.Google Scholar
[2]Altman, C. and Suchy, K. 2004 Wave modes in a magnetoplasma with anisotropic perturbation pressure–fluid and kinetic calculations. J. Plasma Phys. 70, 463–479.CrossRefGoogle Scholar
[3]Suchy, K. 1997 The calculation of the viscosity tensor for a magnetoplasma from the stress balance equation. In Proceedings of the 23rd International Conference on Phenomena in Ionized Gases (ICPIG), Toulouse, Vol. 5, pp. V-6 and V-7.Google Scholar
[4]Braginskii, S. I. 1957 On the modes of plasma oscillations in a magnetic field. Sov. Phys. Dokl. 2, 345–349.Google Scholar
[5]Stringer, T. E. 1963 Low-frequency waves in an unbounded plasma. Plasma Phys. (J. Nuclear Energy, Part C) 5, 89–107.CrossRefGoogle Scholar
[6]Formisano, V. and Kennel, C. F. 1969 Small amplitude waves in high-β plasmas. J. Plasma Phys. 3, 55–74.CrossRefGoogle Scholar
[7]Suchy, K. and Altman, C. 2006 Wave modes in a collision-free multi-species magnetoplasma with anisotropic background and perturbation pressures. J. Plasma Phys. 72, 105–115.CrossRefGoogle Scholar
[8]Suchy, K. and Altman, C. 1997 Eigenmode scattering theorems for electromagnetic-acoustic fields in compressible magnetoplasmas with anisotropic pressure. J. Plasma Phys. 58, 247–257.CrossRefGoogle Scholar
[9]Stix, T. H. 1992 Waves in Plasma. New York: American Institute of Physics.Google Scholar
[10]Akhiezer, A. I., Akhiezer, I. A., Polovin, R. V., Sitenko, A. G. and Stepanov, K. N. 1975 Plasma Electrodynamics, Vol. 1: Linear Theory. Oxford: Pergamon.Google Scholar
[11]Hasegawa, A. and Sato, T. 1989 Space Plasma Physics, Vol. 1: Stationary Processes. Berlin: Springer.CrossRefGoogle Scholar
[12]Brambilla, M. 1998 Kinetic Theory of Plasma Waves. Oxford: Clarendon Press.CrossRefGoogle Scholar
[13]Stix, T. H. 1962 The Theory of Plasma Waves. New York: McGraw-Hill.Google Scholar
[14]Holter, Ø., Altman, C., Roux, A., Perraut, S., Pedersen, A., Pécseli, H., Lybekk, B., Trulsen, J., Korth, A. and Kremser, G. 1995 Characterization of low frequency oscillations at substorm breakup. J. Geophys. Res. 100, 19109–19119.CrossRefGoogle Scholar
[15]Roux, A., Perraut, S., Robert, P., Morane, A., Pedersen, A., Korth, A., Kremser, G., Aparicio, B., Rodgers, D. and Pellinen, R. 1991 Plasma sheet instability related to the westward traveling surge. J. Geophys. Res. 96, 17697–17714.CrossRefGoogle Scholar
[16]Pu, Z. Y., Friedel, R. H., Korth, A., Zong, Q. G., Chen, Z. X., Roux, A. and Perraut, S. 1998 Evaluation of energetic particle parameters in the near-earth magnetotail derived from flux asymmetry observations. Ann. Geophys. 16, 283–291.CrossRefGoogle Scholar
[17]Sagdeev, R. Z. and Shafranov, V. D. 1961 On the instability of a plasma with an anisotropic distribution of velocities in a magnetic field. Sov. Phys. JETP 12, 130–132.Google Scholar
[18]Kennel, C. F. and Wong, H. V. 1966 High ion β pitch-angle instability. Phys. Rev. Lett. 17, 245–246.CrossRefGoogle Scholar
[19]Kremser, G., Korth, A., Ullaland, S. L., Perraut, S., Roux, A., Pedersen, A., Schmidt, R. and Tanskanen, P. 1988 Field-aligned beams of energetic electrons (16 keV ≤ E ≤ 80 keV) observed at geosynchronous orbit at substorm onsets. J. Geophys. Res. 93, 14453–14464.CrossRefGoogle Scholar
[20]Gary, S. P. 1993 Theory of Space Plasma Microinstabilities. Cambridge: University Press.CrossRefGoogle Scholar
[21]Belmont, G. and Rezeau, L. 1987 Finite Larmor radius effects: the two-fluid approach. Ann. Geophys. 5A, 59–70.Google Scholar
[22]Snyder, P. B., Hammett, G. W. and Dorland, W. 1997 Landau fluid models of collisionless magnetohydrodynamics. Phys. Plasmas 4, 3974–3985.CrossRefGoogle Scholar