Solar dynamo theory and the models of Babcock and Leighton
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The dynamo theory of the solar cycle as developed by Parker and others, and the observational models of Babcock and Leighton have been examined, with the conclusion that the dynamo theory is not applicable to the Sun and that the models fail.
An essential part of the theory is an adequate effective diffusion coefficient. Fields are continuously sheared and amplified and, in this theory, these may not be allowed to accumulate; all subsurface fields of an old cycle must be eliminated. Ohmic diffusion is negligible and turbulent diffusion is invoked. However, this requires that all solar fields are tangled to a small scale, which is contrary to observation; for Hale's polarity laws are strictly observed, and large-scale surface features are common at the end of an 11-yr cycle in the same general area where new fields are appearing.
The erupted (sunspot) fields lie generally above the unerupted, toroidal fields so that, even if they are merged as required, the centroid of the new system would be above that of the old. The result is not a steady-state oscillator, as required, but the complete loss of the solar field.
It is concluded that for these and other reasons a shallow, reversing field is unacceptable, and that a deeply penetrating field is required. Reference is made to an alternative theory of the solar cycle based on a deep magnetic field.
KeywordsSolar Cycle Complete Loss Effective Diffusion Alternative Theory Turbulent Diffusion
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- Allen, C. W.: 1963, Astrophysical Quantities, 2nd ed., Univ. of London.Google Scholar
- Babcock, H. W.: 1961, Astrophys. J. 133, 572.Google Scholar
- Braginskii, S. I.: 1964, Soviet Phys. - JETP 20, 726 and 1462.Google Scholar
- Brunner, W.: 1930, Astron. Mitt. Zürich, No. 124, p. 67.Google Scholar
- Bumba, V. and Howard, R. F.: 1965, Astrophys. J. 141, 1492 and 1502.Google Scholar
- Bumba, V., Howard, R., Martres, M. J., and Soru-Iscovici, I.: 1968, in K. O. Kiepenheuer (ed.), ‘Structure and Development of Solar Active Regions’, IAU Symp. 35, 13.Google Scholar
- Cowling, T. G.: 1957, Magnetohydrodynamics, Interscience, New York.Google Scholar
- de Jager, C.: 1959, Handbuch der Physik 52, 80.Google Scholar
- Gilman, P. A.: 1969, Solar Phys. 8, 316.Google Scholar
- Hale, G. E. and Nicholson, S. B.: 1938, Carnegie Inst. Wash. Publ., No. 498.Google Scholar
- Haurwitz, M. W.: 1968, Astrophys. J. 151, 351.Google Scholar
- Howard, R.: 1965, in R. Lüst (ed), ‘Stellar and Solar Magnetic Fields’, IAU Symp. 22, 129.Google Scholar
- Kiepenheuer, K. O.: 1953, The Sun, (ed. by G. P. Kuiper), Univ. of Chicago Press.Google Scholar
- Kiepenheuer, K. O.: 1970, Trans. IAU 14A, 77.Google Scholar
- Kraichnan, R. H. and Nagarajan, S.: 1967, Phys. Fluids 10, 859.Google Scholar
- Leighton, R. B.: 1964, Astrophys. J. 140, 1547.Google Scholar
- Leighton, R. B.: 1969, Astrophys. J. 156, 1.Google Scholar
- Parker, E. N.: 1955, Astrophys. J. 121, 491.Google Scholar
- Parker, E. N.: 1970a, Ann. Rev. Astron. Astrophys. 8, 1.Google Scholar
- Parker, E. N.: 1970b, Astrophys. J. 162, 665.Google Scholar
- Parker, E. N.: 1971a, Astrophys. J. 163, 279.Google Scholar
- Parker, E. N.: 1971b, Astrophys. J. 164, 491.Google Scholar
- Piddington, J. H.: 1971, Proc. Astron. Soc. Australia 2, 7.Google Scholar
- Ribes, E. and Unno, W.: 1971, Proc. Astron. Soc. Australia, 2, 54.Google Scholar
- Richardson, R. S. and Schwarzschild, M.: 1953, Accademia Nazionale Lincei, Convegno 11, Rome 1952.Google Scholar
- Spitzer, L.: 1968, Diffuse Matter in Space, Wiley-Interscience, New York.Google Scholar
- Steenbeck, M. and Krause, F.: 1969, Astron. Nachr. 291, 49.Google Scholar
- Ward, F.: 1965, Astrophys. J. 141, 534.Google Scholar
- Williams, I. P. and Cremin, A. W.: 1968, Quart. J. Roy. Astron. Soc. 9, 40.Google Scholar