Abstract
The observed properties of small-scale solar magnetic fields are reviewed. Most of the magnetic flux in the photosphere is in the form of strong fields of about 100–200 mT (1–2 kG), which have remarkably similar properties regardless of whether they occur in active or quiet regions. These fields are associated with strong atmospheric heating. Flux concentrations decay at a rate of about 107 Wb s−1, independent of the amount of flux in the decaying structure. The decay occurs by smaller flux fragments breaking loose from the larger ones, i.e. a transfer of magnetic flux from smaller to larger Fourier wave numbers, into the wave-number regime where ohmic diffusion becomes significant. This takes place in a time-scale much shorter than the length of the solar cycle.
The field amplification occurs mainly below the solar surface, since very little magnetic flux appears in diffuse form in the photosphere, and the life-time of the smallest flux elements is very short. The observations further suggest that most of the magnetic flux in quiet regions is supplied directly from below the solar surface rather than being the result of turbulent diffusion of active-region magnetic fields.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Similar content being viewed by others
References
Alfvén, H.: 1967, in Hindmarsh, Lowes, Roberts, and Runcorn (eds.), Magnetism and the Cosmos, Oliver & Boyd, Edinburgh/London, p. 246.
Beckers, J. M.: 1963, Astrophys. J. 138, 648.
Beckers, J. M.: 1968, Solar Phys. 3, 367.
Beckers, J. M.: 1972, Ann. Rev. Astron. Astrophys. 10, 73.
Beckers, J. M., Noyes, R. W., and Pasachoff, J. M.: 1966, Astron. J. 71, 155.
Beckers, J. M. and Schröter, E. H.: 1968a, Solar Phys. 4, 142.
Beckers, J. M. and Schröter, E. H.: 1968b, Solar Phys. 4, 165.
Bray, R. J. and Loughhead, R. E.: 1961, Australian J. Phys. 14, 14.
Bray, R. J. and Loughhead, R. E.: 1974, The Solar Chromosphere, Chapman and Hall, London.
Bumba, V.: 1963, Bull. Astron. Inst. Czech. 19, 91.
Bumba, V.: 1967, Solar Phys. 1, 371.
Bumba, V. and Howard, R.: Astrophys. J. 141, 1502.
Caccin, B., Falciani, R., and Donati-Falchi, A.: 1974, Solar Phys. 35, 31.
Chapman, G. A.: 1970, Solar Phys. 14, 315.
Chapman, G. A.: 1974, Astrophys. J. 191, 255.
Chapman, G. A. and Sheeley, N. R. Jr.: 1968, Solar Phys. 5, 442.
Deubner, F. L.: 1975, in C. Chiuderi, M. Landini, and A. Righini (eds.), ‘First European Solar Meeting (Florence, February 25–27, 1975)’, Osservazioni e Memorie Osservatorio di Arcetri 105, 39.
Dravins, D.: 1974, in R. G. Athay (ed.), ‘Chromospheric Fine Structure’, IAU Symp. 56, 257.
Dunn, R. B. and Zirker, J. B.: 1973, Solar Phys. 33, 281.
Foukal, P.: 1972, Astrophys. J. 173, 439.
Foukal, P. and Jokipii, J. R.: 1975, Astrophys. J. 199, L71.
Frazier, E. N.: 1970, Solar Phys. 14, 89.
Frazier, E. N.: 1971, Solar Phys. 21, 42.
Frazier, E. N.: 1972, Solar Phys. 26, 130.
Frazier, E. N.: 1974, Solar Phys. 38, 69.
Frazier, E. N. and Stenflo, J. O.: 1972, Solar Phys. 27, 330.
Giovanelli, R. G. and Ramsay, J. V.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 293.
Gokhale, M. H. and Zwaan, C.: 1972, Solar Phys. 26, 52.
Golub, L., Krieger, A. S., Silk, J. K., Timothy, A. F., and Vaiana, G. S.: 1974, Astrophys. J. 189, L93.
Gopasyuk, S. I., Kotov, V. A., Severny, A. B., and Tsap, T. T.: 1973, Solar Phys. 31, 307.
Hale, G. E.: 1908, Astrophys. J. 28, 100.
Hale, G. E.: 1927, Nature 119, 708.
Hale, G. E. and Ellerman, F.: 1903, Publ. Yerkes Obs. 3, 1.
Harvey, J. W.: 1971, Publ. Astron. Soc. Pacific 83, 539.
Harvey, J. W.: 1974, Flare Related Magnetic Field Dynamics, NCAR, Boulder, Colorado, p. 1.
Harvey, J. W. and Hall, D.: 1975, Abstract of Report at the 146th AAS meeting, San Diego, California, 17–20 August, 1975.
Harvey, J. W. and Livingston, W.: 1969, Solar Phys. 10, 283.
Harvey, J., Livingston, W., and Slaughter, C.: 1972, Line Formation in a Magnetic Field, NCAR, Boulder, Colorado, p. 227.
Harvey, K. and Harvey, J.: 1973, Solar Phys. 28, 61.
Harvey, K. L. and Martin, S. F.: 1973, Solar Phys. 32, 389.
Harvey, K. L., Harvey, J. W., and Martin, S. F.: 1975, Solar Phys. 40, 87
Howard, R.: 1971, Solar Phys. 16, 21.
Howard, R.: 1972, Solar Phys. 24, 123.
Howard, R.: 1974, Solar Phys. 38, 59.
Howard, R. and Bhatnagar, A.: 1969, Solar Phys. 10, 245.
Howard, R. and Harvey, J.: 1970, Solar Phys. 12, 23.
Howard, R. and Stenflo, J. 0.: 1972, Solar Phys. 22, 402.
Kopeckÿ, M.: 1971, Bull. Astron. Inst. Czech. 22, 343.
Kotov, V. A.: 1970, Izv. Krymsk. Astrofiz. Obs. 41, 67.
Krat, V. A.: 1973, Solar Phys. 32, 307.
Kuz’minykh, V. D.: 1964, Astron. Zh. 41, 692 (Soviet Astron. 8, 551 ).
Leighton, R. B.: 1964, Astrophys. J. 140, 1547.
Leighton, R. B.: 1965, in R. Lüst (ed), ‘Stellar and Solar Magnetic Fields’, IAU Symp. 22, 158.
Leighton, R. B.: 1969 Astrophys. J. 156, 1.
Leighton, R. B., Noyes, R. W., and Simon, G.: 1962, Astrophys. J. 135, 474.
Lites, B. W.: 1972, NCAR Cooperative Thesis No. 28, University of Colorado and High Altitude Observatory, NCAR, Boulder, Colorado.
Livingston, W.: 1968, Astrophys. J. 153, 929.
Livingston, W. and Harvey, J.: 1969, Solar Phys. 10, 294.
Livingston, W. and Harvey, J.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 51.
Livingston, W. and Harvey, J.: 1975, Bull. Amer. Astron. Soc. 7, 346 (Abstract).
Lynch, D. K., Beckers, J. M., and Dunn, R. B.: 1973, Solar Phys. 30, 63.
Mehltretter, J. P.: 1974, Solar Phys. 38, 43.
Michard, R.: 1956, Ann. Astrophys. 19, 1.
Michard, R.: 1974, in R. G. Athay (ed.), ‘Chromospheric Fine Structure’, IAU Symp. 56, 3.
Milkey, R. W.: 1970, Solar Phys. 14, 62.
Mullan, D. J.: 1974, preprint.
Osterbrock, D. E.: 1961, Astrophys. J. 134, 347.
Parker, E. N.: 1955, Astrophys. J. 121, 491.
Parker, E. N.: 1963, Astrophys. J. 138, 552.
Parker, E. N.: 1970, Ann. Rev. Astron. Astrophys. 8, 1.
Parker, E. N.: 1974a, Astrophys. J. 189, 563.
Parker, E. N.: 1974b, Astrophys. J. 190, 429.
Parker, E. N.: 1974c, Astrophys. Space Sci. 22, 279.
Parker, E. N.: 1974d, Solar Phys. 36, 249.
Parker, E. N.: 1974e, Solar Phys. 37, 127.
Parker, E. N.: 1974e, Solar Phys. 37, 127.
Pasachoff, J. M., Noyes, R. W., and Beckers, J. M.: 1968, Solar Phys. 5, 131.
Peckover, R. S. and Weiss, N. 0.: 1972, Computer Phys. Communications 4, 339.
Piddington, J. H.: 1972, Solar Phys. 22, 3.
Piddington, J. H.: 1973, Solar Phys. 33, 363.
Piddington, J. H.: 1975a, Astrophys. Space Sci. 34, 347.
Piddington, J. H.: 1975b, Astrophys. Space Sci. 35, 269.
Piddington, J. H.: 1975c, Astrophys. Space Sci. 38, 157.
Richardson, R. S.: 1941, Astrophys. J. 93, 24.
Schatten, K. H., Wilcox, J. M., and Ness, N. F.: 1969, Solar Phys. 6, 442.
Schmahl, G.: 1967, Z. Astrophys. 66, 81.
Semel, M.: 1962, Compt. Rend. Acad. Sci. Paris 254, 3978.
Servajean, R.: 1961, Ann. Astrophys. 24, 1.
Severny, A. B.: 1965, Astion. Zh. 42, 217.
Severny, A. B.: 1967, Izv. Krymsk. Astrofiz. Obs. 38, 3.
Severny, A. B.: 1972, in C. de Jager (ed.), Astrophysics and Space Science Library, Vol. 29, 38.
Sheeley, N. R. Jr.: 1966, Astrophys. J. 144, 723.
Sheeley, N. R. Jr.: 1967, Solar Phys. 1, 171.
Sheeley, N. R. Jr.: 1969, Solar Phys. 9, 347.
Sheeley, N. R. Jr.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 310.
Shine, R. A. and Linsky, J. J.: 1974, Solar Phys. 37, 145.
Simon, G. W. and Leighton, R. B.: 1964, Astrophys. J. 140, 1120.
Simon, G. W. and Noyes, R. W.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 663.
Simon, G. W. and Zirker, J. B.: 1974, Solar Phys. 35, 331.
Skumanich, A., Smythe, C., and Frazier, E. N.: 1975, Astrophys. J. 200, 747.
Spruit, H. C.: 1976, to be published.
Sreenivasan, S. R.: 1973a, Physica 67, 323.
Sreenivasan, S. R.: 1973b, Physica 67, 330.
Sreenivasan, S. R. and Thompson, D. L.: 1974, Physica 78, 321.
Steenbeck, M. and Krause, F.: 1969, Astron. Nachr. 291, 49.
Stellmacher, G. and Wiehr, E.: 1971, Solar Phys. 18, 220.
Stellmacher, G. and Wiehr, E.: 1973, Astron. Astrophys. 29, 13.
Stenflo, J. 0.: 1966, Arkiv. Astion. 4, 173.
Stenflo, J. 0.: 1968a, Acta Univ. Lund. II No. 1 (= Medd. Lunds Astron. Obs. Ser. II No. 152 ).
Stenflo, J. O.: 1968b, Acta Univ. Lund. II No. 2 (= Medd. Lunds Astion. Obs. Ser. II No. 153 ).
Stenflo, J. 0.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 101.
Stenflo, J. 0.: 1973, Solar Phys. 32, 41.
Stenflo, J. O.: 1974a, Solar Phys. 36, 495.
Stenflo, J. O.: 1974b, Flare Related Magnetic Field Dynamics, NCAR, Boulder, Colorado, p. 153.
Stenflo, J. 0.: 1975, Solar Phys. 42, 79.
Steshenko, N. V.: 1960, Izv. Krymsk. Astrofiz. Obs. 22, 49.
Steshenko, N. V.: 1967, Izv. Krymsk. Astrofiz. Obs. 37, 21.
Stix, M.: 1974, Astion. Astrophys. 37, 121.
Stoyanova, M. N.: 1970, Solar Phys. 15, 349.
Tanenbaum, A. S., Wilcox, J. M., Frazier, E. N., and Howard, R.: 1969, Solar Phys. 9, 328.
Timothy, A. F., Krieger, A. S., and Vaiana, G. S.: 1975, Solar Phys. 42, 135.
Ulmschneider, P.: 1971, Astron. Astrophys. 14, 275.
Unno, W.: 1959, Astrophys. J. 129, 375.
Vorpahl, J.: 1974, in R. G. Athay (ed.), ‘Chromospheric Fine Structure’, IAU Symp. 56, 197.
Vrabec, D.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 329.
Vrabec, D.: 1974, in R. G. Athay (ed.), ‘Chromospheric Fine Structure’, IAU Symp. 56, 201.
Weart, S.: 1972, Astrophys. J. 177, 271.
Wiehr, E. and Wittmann, A.: 1975, private communication.
Wilcox, J. M. and Howard, R.: 1970, Solar Phys. 13, 251.
Wilcox, J. M., Schatten, K. H., Tanenbaum, A. S., and Howard, R.: 1970, Solar Phys. 14, 255.
Wilson, P. R.: 1969, Solar Phys. 6, 364.
Zirin, H. and Tanaka, K.: 1973, Solar Phys. 32, 173.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1976 IAU
About this chapter
Cite this chapter
Stenflo, J.O. (1976). Small-Scale Solar Magnetic Fields. In: Bumba, V., Kleczek, J. (eds) Basic Mechanisms of Solar Activity. International Astronomical Union / Union Astronomique Internationale, vol 71. Springer, Dordrecht. https://doi.org/10.1007/978-94-010-1481-6_7
Download citation
DOI: https://doi.org/10.1007/978-94-010-1481-6_7
Publisher Name: Springer, Dordrecht
Print ISBN: 978-90-277-0681-2
Online ISBN: 978-94-010-1481-6
eBook Packages: Springer Book Archive