Abstract
Applying an Alfvén-Wave-Extended-QRH-approximation and the method of characteristics, we solve the equations of motion for outwardly propagating Alfvén waves analytically for three different cases of an azimuthal dependence of the background solar wind, (a) for a pure fast-slow stream configuration, (b) for the situation where the high-speed stream originates from a diverging magnetic field region, and (c) for the case of (b) and an initially decreasing density configuration (‘coronal hole’). The reaction of these waves on the background state as well as mode-mode coupling effects are neglected. These three solar wind models are discussed shortly. For the superimposed Alfvén waves we find, on an average, that there is a strong azimuthal dependence of all relevant wave parameters which, correlated with the azimuthal distributions of the solar wind variables, leads to good agreements with observations. The signature of high-speed streams and these correlations could clearly indicate solar wind streams originating from ‘coronal holes’. Contrary to the purely radial dependent solar wind, where outwardly propagating Alfvén waves are exclusively refracted towards the radial direction, we now find a refraction nearly perpendicular to the direction of the interplanetary magnetic field in the compression region and closely towards the magnetic field direction down the trailing edge and in the low-speed regime.
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Alazraki, G. and Couturier, P.: 1971,Astron. Astrophys. 13, 380.
Altschuler, M. D., Trotter, D. E., and Orrall, F. Q.: 1972,Solar Phys. 26, 354.
Barnes, A. and Hollweg, J. V.: 1974,J. Geophys Res. 79, 2302.
Belcher, J. W.: 1971,Astrophys. J. 168, 509.
Belcher, J. W. and Davis, L., Jr.: 1971,J. Geophys. Res. 76, 3534.
Burlaga, L. F.: 1968,Solar Phys. 4, 67.
Burlaga, L. F.: 1972,Solar Wind, NASA Scienific and Technical Information Office, Washington, D.C., p. 309.
Burlaga, L. F., Ogilvie, K. W., Fairfield, D. H., Montgomery, M. D., and Bame, S. J.: 1971,Astrophys. J. 164, 137.
Courant, R. and Hilbert, D.: 1962,Methods of Mathematical Physics, Interscience Publishers, New York, Vol. II, p. 62.
Daily, W. D.: 1973,J. Geophys. Res. 78, 2043.
Dobrovolny, M.: 1974, ‘Alfvén Wave Instability in the Solar Wind’, presented at the Asilomar Solar Wind Conference.
Fisk, L. A. and Sari, J. W.: 1973,J. Geophys. Res. 78, 6729.
Garrett, H. B., Dessler, A. J., and Hill, T. W.: 1974, ‘Influence of Solar-Wind Variability on Geomagnetic Activity’, submitted toJ. Geophys. Res.
Goldstein, M. L. and Eviatar, A.: 1973,Astrophys. J. 179, 627.
Gosling, J. T., Hundhausen, A. J., Pizzo, V., and Asbridge, J. R.: 1972,J. Geophys. Res. 77, 5442.
Hollweg, J. V.: 1971,J. Geophys. Res. 76, 5155.
Hollweg, J. V.: 1972,Cosmic Electrodyn. 2, 423.
Hollweg, J. V.: 1973,J. Geophys. Res. 78, 3643.
Hollweg, J. V.: 1974,J. Geophys. Res. 79, 1539.
Hundhausen, A. J.: 1970,Rev. Geophys. Space Phys. 8, 729.
Jokipii, J. R.: 1973,Astrophys. J. 182, 585.
Krieger, A. S., Timothy, A. F., and Roelof, E. C.: 1973,Solar Phys. 29, 505.
Martin, R. N., Belcher, J. W., and Lazarus, A. J.: 1973,J. Geophys. Res. 78, 3653.
Matsuda, T. and Sakurai, T.: 1972,Cosmic Electrodyn. 3, 97.
Munro, R. H. and Withbroe, G. L.: 1972,Astrophys. J. 176, 511.
Neupert, W. M. and Pizzo, V.: 1973, ‘Solar Coronal Holes as Sources of Recurrent Geomagnetic Disturbances’, submitted toJ. Geophys. Res.
Olbers, D. J. and Richter, A. K.: 1973,Astrophys. Space Sci. 20, 373.
Richter, A. K. and Olbers, D. J.: 1974,Astrophys. Space Sci. 26, 95.
Sakurai, T.: 1971,Cosmic Electrodyn. 1, 460.
Siscoe, G. L.: 1972,J. Geophys. Res. 77, 27.
Urch, I. H.: 1972,Cosmic Electrodyn. 3, 316.
Völk, H. J., Morfill, G., Alpers, W., and Lee, M. A.: 1974,Astrophys. Space Sci. 26, 267.
Wilcox, J. M. and Ness, N. F.: 1965,J. Geophys. Res. 70, 5793.
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Richter, A.K. Wave-trains in the solar wind. Astrophys Space Sci 36, 383–405 (1975). https://doi.org/10.1007/BF00645262
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DOI: https://doi.org/10.1007/BF00645262