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Stability of Alfvén wings in uniform plasmas

Published online by Cambridge University Press:  01 December 2007

P. A. SALLAGO
Affiliation:
Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina (pato@fcaglp.unlp.edu.ar, amp@fcaglp.unlp.edu.ar)
A. M. PLATZECK
Affiliation:
Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque s/n, 1900 La Plata, Argentina (pato@fcaglp.unlp.edu.ar, amp@fcaglp.unlp.edu.ar)

Abstract

A conducting source moving uniformly through a magnetized plasma generates, among a variety of perturbations, Alfvén waves. An interesting characteristic of Alfvén waves is that they can build up structures in the plasma called Alfvén wings. These wings have been detected and measured in many solar system bodies, and their existence has also been theoretically proven. However, their stability remains to be studied. The aim of this paper is to analyze the stability of an Alfvén wing developed in a uniform background field, in the presence of an incompressible perturbation that has the same symmetry as the Alfvén wing, in the magnetohydrodynamic approximation. The study of the stability of a magnetohydrodynamic system is often performed by linearizing the equations and using either the normal modes method or the energy method. In spite of being applicable for many problems, both methods become algebraically complicated if the structure under analysis is a highly non-uniform one. Palumbo has developed an analytical method for the study of the stability of static structures with a symmetry in magnetized plasmas, in the presence of incompressible perturbations with the same symmetry as the structure (Palumbo 1998 Thesis, Universidad de Firenze, Italia). In the present paper we extend this method for Alfvén wings that are stationary structures, and conclude that in the presence of this kind of perturbation they are stable.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

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References

Agim, Y. Z. and Tataronis, J. A. 1985 J. Plasma Phys. 34, 337.CrossRefGoogle Scholar
Buti, B. and Goldstein, B. E. 2003 Adv. Space Res. 32 (3), 291.CrossRefGoogle Scholar
Drell, S. D., Forley, H. M. and Ruderman, M. A. 1965 J. Geophys. Res. 70, 3131.CrossRefGoogle Scholar
McKenzie, J. F. 1991 J. Geophys. Res. 96, 9491.CrossRefGoogle Scholar
Neubauer, F. M. 1980 J. Geophys. Res. 85, 1171.CrossRefGoogle Scholar
Neubauer, F. M. 1999 J. Geophys. Res. 104, 28 671.CrossRefGoogle Scholar
Palumbo, L. J. and Platzeck, A. M. 1998 J. Plasma Phys. 60, 449.CrossRefGoogle Scholar
Palumbo, L. J. Contribution to the development of an analytical methodology for the study of the stability of magnetized plasmas. Thesis, Universidad de Firenze, Italia, 1998.Google Scholar
Priest, E. R. 1982 Solar Magnetohydrodynamics. Norwell, MA: D. Reidel.CrossRefGoogle Scholar
Sallago, P. A. and Platzeck, A. M. 2000 J. Geophys. Res. 105, 27 393.CrossRefGoogle Scholar
Sallago, P. A. and Platzeck, A. M. 2002 J. Plasma Phys. 67 (5), 321.CrossRefGoogle Scholar
Simpson, D. M., Ruderman, M. S. and Erdélyi, R. 2006 Astron. Astrophys. 452 (2), 641.CrossRefGoogle Scholar
Sommerfeld, A. 1949 Partial Differential Equations in Physics. New York: Academic Press.Google Scholar
Tsinganos, K. C. 1982 Astrophys. J. 252, 775.CrossRefGoogle Scholar
Williams, D. J., Mauk, B. and McEntire, R. W. 1998 J. Geophys. Res. 103, 17 523.CrossRefGoogle Scholar