Advertisement

Observations of Small-Scale Photospheric Magnetic Fields

  • J. Harvey
Part of the International Astronomical Union / Union Astronomique Internationale book series (IAUH, volume 4-2)

Abstract

If the Sun is observed like a star, without spatial resolution, its magnetic field seldom exceeds 1 Gauss. But with high spatial resolution the field is seen to be largely concentrated into kG structures. Observations of the structure and dynamics of solar magnetic fields can therefore provide a guide to the nature of magnetic fields of other stars which cannot be resolved. Solar activity and the structure of the chromosphere and inner corona are intimately linked with magnetism and a complete understanding of these features often depends on magnetic field details. There are unsolved physical problems involving solar magnetic fields which have challenged many physicists. For example, confinement of small-scale fields in kG structures is a problem of current interest (Parker, 1976; Piddington, 1976; Spruit, 1976). Solar observers are no less challenged since the Sun presents us with a complicated magnetic field having a range of scales from global to less than the scale of our best observations as illustrated in Figures 1, 2, and 3. This paper is a survey of observational techniques and results at the small-scale end of the spectrum of sizes in the solar photosphere. This topic has been frequently reviewed (e.g. Athay, 1976; Beckers, 1976; Deubner, 1975; Howard, 1972; Mullan, 1974; Severny, 1972; Stenflo, 1975) so that recent work is emphasized here.

Keywords

Magnetic Field Solar Phys Line Profile Disk Center Spectrum Line 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Athay, R. G.: 1976, The Solar Chromosphere and Corona: Quiet Sun, D. Reidel, Dordrecht, Ch. 4.Google Scholar
  2. Beckers, J. M.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 3.Google Scholar
  3. Beckers, J. M.: 1975, Environmental Research Papers 499, Air Force Cambridge Research Laboratories.Google Scholar
  4. Beckers, J. M.: 1976, to be published in the Proceedings of the AGU International Symposium on Solar Terrestrial Physics (Boulder, Colorado).Google Scholar
  5. Beckers, J. M. and Schröter, E. H.: 1968, Solar Phys. 4, 142.ADSCrossRefGoogle Scholar
  6. Chapman, G. A.: 1972, Solar Phys. 26, 299.ADSCrossRefGoogle Scholar
  7. Chapman, G. A.: 1976, submitted to Astrophys. J. Google Scholar
  8. Chapman, G. A. and Sheeley, N. R.: 1968, Solar Phys. 5, 442.ADSCrossRefGoogle Scholar
  9. Deubner, F.-L.: 1975, Oss. e Mem. Oss. Arcetri, no. 105, 39.Google Scholar
  10. Dunn, R. B. and Zirker, J. B.: 1973, Solar Phys. 33, 281.ADSGoogle Scholar
  11. Efanov, V. A., Moiseev, I. G., and Severny, A. B.: 1974, Nature 249, 330 (also Izv. Krymsk. Astrofiz. Obs. 53, 121).ADSCrossRefGoogle Scholar
  12. Frazier, E. N.: 1970, Solar Phys. 14, 89.ADSCrossRefGoogle Scholar
  13. Frazier, E. N.: 1974, Solar Phys. 38, 69.ADSCrossRefGoogle Scholar
  14. Frazier, E. N. and Stenflo, J. O.: 1972, Solar Phys. 27, 330.ADSCrossRefGoogle Scholar
  15. Giovanelli, R. G. and Ramsay, J. V.: 1971, in R. Howard (ed.) ‘Solar Magnetic Fields’, IAU Symp. 43, 293.Google Scholar
  16. Gopasyuk, S. I., Kotov, V. A., Severny, A. B. and Tsap, T. T.: 1973, Solar Phys. 31, 307.ADSCrossRefGoogle Scholar
  17. Harvey, J. and Hall, D.: 1975, Bull. Am. Astron. Soc. 7, 459.ADSGoogle Scholar
  18. Harvey, J. and Livingston, W.: 1969, Solar Phys. 10, 283.ADSCrossRefGoogle Scholar
  19. Heasley, J.: 1976, personal communication.Google Scholar
  20. Howard, R.: 1972, in C. P. Sonnett, P. J. Coleman and J. M. Wilcox (eds.) ‘Solar Wind’, NASA SP-308, 3.Google Scholar
  21. Howard, R. and Bhatnagar, A.: 1969, Solar Phys. 10, 245.ADSCrossRefGoogle Scholar
  22. Howard, R. and Stenflo, J. O.: 1972, Solar Phys. 22, 402.ADSCrossRefGoogle Scholar
  23. Jäger, F. W.: 1972, Solar Phys. 27, 481.ADSCrossRefGoogle Scholar
  24. Liu, S.-Y.: 1974, Solar Phys. 39, 297.ADSCrossRefGoogle Scholar
  25. Livingston, W. C. and Harvey, J.: 1975, Bull. Am. Astron. Soc. 7, 346.ADSGoogle Scholar
  26. Lynch, D. K.: 1974, Bull. Am. Astron. Soc. 6, 191.Google Scholar
  27. Mehltretter, J. P.: 1974, Solar Phys. 38, 43.ADSCrossRefGoogle Scholar
  28. Mullan, D. J.: 1974, J. Franklin Inst. 298, 341.ADSCrossRefGoogle Scholar
  29. Parker, E. N.: 1976, Astrophys. J. 204, 259.ADSCrossRefGoogle Scholar
  30. Piddington, J. H.: 1976, Astrophys. Space Sci. 40, 73.ADSCrossRefGoogle Scholar
  31. Schoolman, S. A. and Ramsey, H. E.: 1976, Solar Phys., in press.Google Scholar
  32. Schröter, E. H.: 1973, Mitt. Astron. Ges. 32, 55.ADSGoogle Scholar
  33. Seares, F. H.: 1913, Astrophys. J. 38, 99.ADSCrossRefGoogle Scholar
  34. Semel, M.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 37.Google Scholar
  35. Severny, A. B.: 1966, Soviet Astron. — A. J. 10, 367.ADSGoogle Scholar
  36. Severny, A. B.: 1972, in E. R. Dyer (ed.) ‘Solar Terrestrial Physics/1970’, Astrophys. Sp. Science Library 29, 38.Google Scholar
  37. Severny, A. B.: 1976, personal communication.Google Scholar
  38. Sheeley, N. R.: 1966, Astrophys. J. 144, 723.ADSCrossRefGoogle Scholar
  39. Sheeley, N. R.: 1967, Solar Phys. 1, 171.ADSCrossRefGoogle Scholar
  40. Sheeley, N. R.: 1971, in R. Howard (ed.) ‘Solar Magnetic Fields’, IAU Symp. 43, 310.Google Scholar
  41. Simon, G. W. and Zirker, J. B.: 1974, Solar Phys. 35, 331.ADSCrossRefGoogle Scholar
  42. Skumanich, A., Smythe, C., and Frazier, E. N.: 1975, Astrophys. J. 200, 747.ADSCrossRefGoogle Scholar
  43. Smithson, R. C.: 1973, Solar Phys. 29, 365.ADSCrossRefGoogle Scholar
  44. Smithson, R. C.: 1975, Bull. Am. Astron. Soc. 7, 346.ADSGoogle Scholar
  45. Spruit, H. C.: 1976, preprint.Google Scholar
  46. Staude, J.: 1974, Z. Meteorologie 24, 214.ADSGoogle Scholar
  47. Stellmacher, G. and Wiehr, E.: 1971, Solar Phys. 18, 220.ADSCrossRefGoogle Scholar
  48. Stenflo, J. O.: 1966, Ark. Astron. 4, 173.ADSGoogle Scholar
  49. Stenflo, J. O.: 1968, Acta Univ. Lund. II, no. 2.Google Scholar
  50. Stenflo, J. O.: 1971, in R. Howard (ed.), ‘Solar Magnetic Fields’, IAU Symp. 43, 101.Google Scholar
  51. Stenflo, J. O.: 1973, Solar Phys. 32, 41.ADSCrossRefGoogle Scholar
  52. Stenflo, J. O.: 1975, in V. Bumba and J. Kleczek (eds.), ‘Basic Mechanisms of Solar Activity’, IAU Symp. 71, in press.Google Scholar
  53. Stenflo, J. O.: 1975, Solar Phys. 42, 79.ADSCrossRefGoogle Scholar
  54. Steshenko, N. V.: 1967, Izv. Krymsk. Astrofiz. Obs. 37, 21.Google Scholar
  55. Svalgaard, L.: 1976, personal communication.Google Scholar
  56. Tarbell, T. D. and Title, A. M.: 1975, Bull, Am. Astron. Soc. 7, 459.ADSGoogle Scholar
  57. Title, A. M. and Andelin, J. P.: 1971, in R. Howard (ed.) ‘Solar Magnetic Fields’, IAU Symp. 43, 298.Google Scholar
  58. Title, A. M. and Tarbell, T. D.: 1975, Solar Phys. 41, 255.ADSCrossRefGoogle Scholar
  59. Unno, W.: 1956, Pub. Astron. Soc. Japan 8, 108.ADSGoogle Scholar
  60. Unno, W.: 1959, Astrophys. J. 129, 375.ADSCrossRefGoogle Scholar
  61. Vrabec, D.: 1974, in R. G. Athay (ed.), ‘Chromospheric Fine Structure’, IAU Symp. 56, 224.Google Scholar
  62. Wiehr, E.: 1971, Solar Phys. 18, 226.ADSCrossRefGoogle Scholar
  63. Wiehr, E.: 1976, personal communication.Google Scholar

Copyright information

© IAU 1977

Authors and Affiliations

  • J. Harvey
    • 1
  1. 1.Kitt Peak National ObservatoryTucsonUSA

Personalised recommendations