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Symmetries of the triple degenerate DNLS equations for weakly nonlinear dispersive MHD waves

Published online by Cambridge University Press:  13 March 2009

G. M. Webb
Affiliation:
LPL, Department of Planetary Sciences, University of Arizona, Tucson, Arizona 85721, U.S.A.
M. Brio
Affiliation:
Department of Mathematics, University of Arizona, Tucson, Arizona 85721, U.S.A.
G. P. Zank
Affiliation:
Bartol Research Institute, The University of Delaware, Newark, Delaware 19716, U.S.A.

Abstract

Lie symmetries, conservation laws, and Lagrangian and Hamiltonian formulations of the triple degenerate, derivative nonlinear Schrödinger (TDNLS) equations for weakly nonlinear dispersive, magnetohydrodynamic (MHD) waves are derived. The equations describe how Alfvén waves propagating parallel to the background magnetic field B interact with the magneto-acoustic modes near the triple umbilic point where the fast, slow and Alfvén mode phase speeds coincide. The Lie point symmetries are used to derive classical similarity solutions of the equations. In particular, the similarity solutions corresponding to time translation, space translation and rotational invariance symmetries are reduced to quadrature. The dispersionless TDNLS system is of hydrodynamic type, and has three families of characteristics analogous to the slow, intermediate and fast modes of MilD. The Riemann invariants corresponding to each of these families are obtained in closed analytic form. Examples of solitary wave and periodic travelling wave solutions are investigated by plotting the contours of the Hamiltonian H(v, w) in the (v, w) phase plane, where the canonical variables v and w correspond to the normalized transverse magnetic field perturbations. An analysis of the prolongation Lie algebra is carried out in order to investigate the integrability of the equations.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1995

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References

REFERENCES

Bluman, G. W. & Kumei, S. 1989 Symmetries and Differential Equations. Springer-Verlag, New York.CrossRefGoogle Scholar
Brio, M. 1989 a Notes on Numerical Fluid Mechanics 24, 43.Google Scholar
Brio, M. 1989 b Contemp. Maths 100, 55.CrossRefGoogle Scholar
Brio, M. & Rosenau P. 1995 Canadian Appl. Math. Q. (submitted).Google Scholar
Cabannes, H. 1970 Theoretical Magnetofluiddynamics, Academic Press, New York.Google Scholar
Chorin, A. J. & Marsden, J. E. 1979 A Mathematical Introduction to Fluid Mechanics, Springer-Verlag, New York.CrossRefGoogle Scholar
Deconinck, B., Meuris, P. & Verheest, F. 1993 a J. Plasma Phys. 50, 445.CrossRefGoogle Scholar
Deconinck, B., Meuris, P. & Verheest, F. 1993 b J. Plasma Phys. 50, 457.CrossRefGoogle Scholar
Ferapontov, E. V. 1993 CRC Handbook of Lie Group Analysis of Differential Equations (ed. Ibragimov, N. H.), Chap. 14. CRC Press, Boca Raton, Florida.Google Scholar
Hada, T. 1993 Geophys. Res. Lett. 20, 2415.CrossRefGoogle Scholar
Hada, T. 1994 Geophys. Res. Lett. 21, 2275.CrossRefGoogle Scholar
Hada, T., Kennel, C. F. & Buti, B. 1989 J. Geophys. Res. 94, 65.CrossRefGoogle Scholar
Harrison, B. K. & Estabrook, F. B. 1971 J. Math. Phys. 12, 653.CrossRefGoogle Scholar
Ibragimov, N. H. 1985 Transformation Groups Applied to Mathematical Physics. Reidel, Dordrecht.CrossRefGoogle Scholar
Jacobson, N. 1979 Lie Algebras. Dover, New York.Google Scholar
Kakutani, T. & Ono, H. 1969 J. Phys. Soc. Jpn 26, 1305.CrossRefGoogle Scholar
Kaup, D. J. & Newell, A. C. 1978 J. Math. Phys. 19, 798.CrossRefGoogle Scholar
Kawata, T., Kobayashi, N. & Inoue, H. 1980 J. Phys. Soc. Jpn 48, 1371.CrossRefGoogle Scholar
Khabibrakhmnov, I. Kh., Galinsky, V. L. & Verheest, F. 1992 Phys. Fluids B 4, 2538.CrossRefGoogle Scholar
Magri, F. 1978 J. Math. Phys. 19, 1156.CrossRefGoogle Scholar
Mio, K., Ogino, T., Minami, K. & Takeda, S. 1976 J. Phys. Soc. Jpn. 41, 265.CrossRefGoogle Scholar
Mjølhus, E. 1976 J. Plasma Phys. 16, 321.CrossRefGoogle Scholar
Mjølhus, E. 1989 Physica Scripta 40, 227.CrossRefGoogle Scholar
Mjølhus, E. & Wyller, J. 1988 J. Plasma Phys. 40, 299.CrossRefGoogle Scholar
Newell, A. C. 1985 Solitons in Mathematics and Physics. Regional Conference Series in Applied Mathematics, CBMS Vol. 48, SIAM, Philadelphia.CrossRefGoogle Scholar
Olver, P. J. 1986 Applications of Lie Groups to Differential Equations. Springer-Verlag, New York.CrossRefGoogle Scholar
Passot, T. & Sulem, P. L. 1993 Phys. Rev. E 48, 2966.Google Scholar
Passot, T. &Sulem, P. L. 1995 Small Scale Structures in Hydrodynamic and Magnetohyd rod ynamic Turbulence (ed. Meneguzzi, M., Pouquet, A. & Sulem, P. L.), p. 386. Lecture Notes in Physics, Springer-Verlag, Berlin.Google Scholar
Passot, T., Sulem, C. & Sulem, P. L. 1994 Phys. Rev. E 50, 1427.Google Scholar
Rogister, A. 1971 Phys. Fluids 14, 2733.CrossRefGoogle Scholar
Taniuti, T. & Wei, C. C. 1968 J. Phys. Soc. Jpn 24, 941.CrossRefGoogle Scholar
Tsarev, S. P. 1991 Math. USSR Izvestiya 37(2), 397.CrossRefGoogle Scholar
Verheest, F. 1992 J. Plasma Phys. 47, 25.CrossRefGoogle Scholar
Wahlquist, H. D. & Estabrook, F. B. 1975 J. Math. Phys. 16, 1.CrossRefGoogle Scholar
Webb, G. M., Brio, M. & Zank, O. P. 1995 Lie-Bäcklund symmetries of dispersionless MHD model equations near the triple umbilic point. In preparation.CrossRefGoogle Scholar
Wu, C. C. 1990 J. Geophys. Res. 95, 8149.CrossRefGoogle Scholar