Abstract
It is shown that leading and following magnetic field lines are inclined toward each other by a few degrees at nearly all latitudes in both the north and south hemispheres. The amplitudes of these inclinations are lower by about a factor 3 for weak fields than for strong fields. There are significant differences between the hemispheres and from one activity cycle to the next in the leading and following polarity field-line inclinations at latitudes poleward of the activity latitudes. In a narrow latitude zone just south of the solar equator the inclinations of both the leading and following fields reduce to zero (or perhaps slightly negative values). Although one would expect such a zone at the equator, where diffusion will mix field lines with opposite inclinations from the two hemispheres, it is not clear why this zone should be on one side of the equator only. The results discussed here were obtained with Mount Wilson magnetograph data (1967–1992), and are confirmed in many respects with National Solar Observatory/Kitt Peak (NSO/KP) data (1976–1986).
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References
Howard, R. F.: 1989,Solar Phys. 123, 271.
Howard, R. F.: 1991,Solar Phys. 134, 233.
Howard, R. F.: 1994, in R. Rutten and C. Schrijver (eds.),Solar Surface Magnetism, NATO ASI Series C433, Kluwer Academic Publishers, Dordrecht, Holland, p. 297.
Jones, H. P., Duvall, T. L., Jr., Harvey, J. W., Mahaffey, C. T., Schwitters, J. D., and Simmons, J. E.: 1992,Solar Phys. 139, 211.
Lites, B. W.: 1972, Thesis, University of Colorado.
Livingston, W. C., Harvey, J., Pierce, A. K., Schlage, D., Gillespie, B., Simmons, J., and Slaughter, C.: 1976a,Appl. Optics 15, 33.
Livingston, W. C., Harvey, J., Slaughter, C., and Trumbo, D.: 1976b,Appl. Optics 15, 40.
Minnaert, M. G. J.: 1946,Monthly Notices Roy. Astron. Soc. 106, 98.
Sheeley, N. R., Jr., DeVore, C. R., and Boris, J. P.: 1985,Solar Phys. 98, 219.
Sheeley, N. R., Jr., Nash, A. G., and Wang, Y. -M.: 1987,Astrophys. J. 319, 481.
Shrauner, J. A. and Scherrer, P. H.: 1994,Solar Phys. 153, 131.
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Howard, R.F., Stanchfield, D.C.H. Latitude dependence of magnetic field-line inclinations. Sol Phys 156, 29–39 (1995). https://doi.org/10.1007/BF00669573
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DOI: https://doi.org/10.1007/BF00669573