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Solar Second Harmonic Plasma Emission and the Head-on Approximation

Published online by Cambridge University Press:  25 April 2016

A. J. Willes
Affiliation:
Department of Theoretical Physics and Research Centre for Theoretical Astrophysics, School of Physics, University of Sydney, NSW 2006, Australia. [email protected]
P. A. Robinson
Affiliation:
Department of Theoretical Physics and Research Centre for Theoretical Astrophysics, School of Physics, University of Sydney, NSW 2006, Australia. [email protected]
D. B. Melrose
Affiliation:
Department of Theoretical Physics and Research Centre for Theoretical Astrophysics, School of Physics, University of Sydney, NSW 2006, Australia. [email protected]

Abstract

The coalescence of two Langmuir waves, L and L′, produces emission at twice the plasma frequency in type II and type III solar radio bursts. The analysis of the coalescence process is usually simplified by assuming the head-on approximation, where the wavevectors of the coalescing waves satisfy kL′ ≈ −kL, corresponding to the two Langmuir waves meeting head on. However, this is not always a valid approximation, particularly when the peak of the Langmuir spectrum lies at small wavenumbers, for narrow band spectra, and for spectra with broad angular ranges. Realistic Langmuir wave spectra are used to investigate the effects of relaxing the head-on approximation.

Type
Solar and Solar System
Copyright
Copyright © Astronomical Society of Australia 1995

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References

Cairns, I. H., 1986, PhD thesis, Univ. Sydney Google Scholar
Cairns, I. H. 1987a, J. Plasma Phys., 38, 169 Google Scholar
Cairns, I. H. 1987b, J. Plasma Phys., 38, 179 Google Scholar
Dulk, G. A., Steinberg, J. L., Hoang, S., & Goldman, M. V., 1987, A&A, 173, 366 Google Scholar
Ginzburg, V. L., & Zheleznyakov, V. V., 1958, Sov. Astron. AJ, 2, 653 Google Scholar
Lin, R. P., Potter, D. W., Gurnett, D. A., & Scarf, F. L., 1981, ApJ, 251, 364 Google Scholar
Melrose, D. B. 1970a, Aust. J. Phys., 23, 871 Google Scholar
Melrose, D. B. 1970b, Aust. J. Phys., 23, 885 Google Scholar
Melrose, D. B., 1980, Space Sci. Rev., 26, 3 Google Scholar
Melrose, D. B., 1982, Sol. Phys., 79, 173 Google Scholar
Melrose, D.B., & Stenhouse, J. E., 1979, A&A, 73, 151 Google Scholar
Nelson, G. J., & Melrose, D. B., 1985, in Solar Radiophysics, ed. McLean, D. J. & Labrum, N. R. (Cambridge Univ. Press)Google Scholar
Poquérusse, M. 1994, A&A, 286, 611 Google Scholar
Robinson, P. A., & Newman, D. L., 1989, Phys. Fluids B, 1, 2319 Google Scholar
Robinson, P. A., Newman, D. L., & Rubenchik, A. M., 1992, Phys. Fluids B, 4, 2509 Google Scholar
Robinson, P. A., Willes, A. J., & Cairns, I. H., 1993, ApJ, 408, 720 Google Scholar
Smith, D. F., 1970, Adv. Astron. Astrophys., 7, 147 Google Scholar
Smith, D. F., 1972, ApJ, 174, 643 Google Scholar