Fine Structure of Photospheric Faculae

  • R. Muller
Conference paper
Part of the International Astronomical Union book series (IAUS, volume 138)


Properties of the photospheric bright points associated with magnetic flux tubes are reviewed both in faculae (facular points) and in the photospheric network (network bright points — NBPs) out of active regions. A special attention is given to their size distribution, to their location relative to the granular, mesogranular and supergranular patterns, and to their relation with the small scale magnetic features, both in active and quiet regions. In particular a new granulation movie reveals that NBPs form in large intergranular spaces, compressed by the surrounding granules.

At the center of the solar disk, bright points are much brighter than the mean photosphere; their contrast increases toward the limb up to μ = 0.3 − 0.2 and then decreases to the limb, as it is now widely accepted. But, all the published contrasts are of little significance because of center-to-limb selection effects. New center-to-limb contrast variations of individual network bright points are presented, which take into account the selection effects.


Solar Phys Flux Tube Disk Center Bright Point Magnetic Flux Tube 
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.


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  1. Bray, R.J. and Loughhead, R.E. (1964), Sunspots, Chapman and Hall, Ltd, London.Google Scholar
  2. Chapman, G.A. and Sheeley, N.R. (1968) ‘The photospheric network’, Solar Phys. 5, 442–. ADSCrossRefGoogle Scholar
  3. Dunn, R.B. and Zirker, J.B. (1973) ‘The solar filigree’, Solar Phys. 33, 281–304.ADSGoogle Scholar
  4. Harvey, J.W.( 1977) ‘Photospheric magnetic and velocity fields in active regions’, in E.A. Müller (ed.), Highlights of Astronomy, 4, 223. Google Scholar
  5. Hirayama, T. (1978) Publ. Astron. Soc. Japan 30,337.ADSGoogle Scholar
  6. Hirayama, T., Hamano, S. and Mizugaki, K. (1985) ‘Precise wideband photometry of photospheric faculae with an emphases on the disk center’, Solar Phys. 99, 43.ADSCrossRefGoogle Scholar
  7. Hirayama, T. and Moriyama, F. (1979) ‘Center-to-limb variation of the intensity of the photospheric faculae’, Solar Phys. 63, 251.ADSCrossRefGoogle Scholar
  8. Martin, S.F. (1988) ‘The identification and interaction of network, intranetwork and ephemeral-region magnetic fields’, Solar Phys. 117, 243–259.ADSCrossRefGoogle Scholar
  9. Mehltretter, J.P. (1974) ‘Observations of photospheric faculae at the center of the solar disk’, Solar Phys. 38, 43–57.ADSCrossRefGoogle Scholar
  10. Muller, R. (1975) ‘A model of photospheric faculae deduced from white light high resolution pictures’, Solar Phys. 45, 105–114.ADSCrossRefGoogle Scholar
  11. Muller, R. (1977) ‘Morphological properties and origin of the photospheric facular granules’, Solar Phys. 52, 249–262.ADSCrossRefGoogle Scholar
  12. Muller, R. (1983) ‘The dynamical behavior of facular points in the quiet photosphere’, Solar Phys. 85, 113–121.ADSCrossRefGoogle Scholar
  13. Muller, R. and Keil, S.L. (1983) ‘The characteristic size and brightness of facular points in the quiet photosphere’, Solar Phys. 87, 243–250.ADSCrossRefGoogle Scholar
  14. Muller, R. and Ména B. (1987) ‘Motions around a decaying sunspot’, Solar Phys. 112, 295–303.ADSCrossRefGoogle Scholar
  15. Muller, R. and Roudier, Th. (1984) ‘Variability of the quiet photospheric network’, Solar Phys. 94, 33–47.ADSCrossRefGoogle Scholar
  16. Muller, R., Roudier, Th. and Hulot, J.C. (1989) ‘Perturbation of the granular pattern by the presence of magnetic flux tubes’, Solar Phys. 119, 229–243.ADSCrossRefGoogle Scholar
  17. Schüssler, M. and Solanki, S.K. (1988) ‘Continuum intensity of magnetic flux concentrations: are magnetic elements bright points?’, Astron. Astrophys. 192, 338–342.ADSGoogle Scholar
  18. Spruit, H.C. and Zwaan, C. (1981) ‘The size dependance of contrasts and numbers of small magnetic flux tubes in an active region’, Solar Phys. 70, 207–228.ADSCrossRefGoogle Scholar
  19. Stenflo, J.O. (1973) ‘Magnetic-field structure of the photospheric network’, Solar Phys. 32, 41–63.ADSCrossRefGoogle Scholar
  20. Title, A.M., Tarbell, T.O. and Topka, K.P. (1987) ‘On the relation between magnetic field structures and granulation’, Astrophys. J. 317, 892–899.ADSCrossRefGoogle Scholar

Copyright information

© International Astronomical Union 1990

Authors and Affiliations

  • R. Muller
    • 1
  1. 1.Pic Du Midi ObservatoryBagnères de BigorreFrance

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