Abstract
Observations of the penumbral intensity of sunspots in 13 wavelength regions are presented. In 4 wavelength regions 54 sunspots are measured. In the other wavelength regions the number of sunspots considered ranges from 3–19.
The penumbral intensity alters with position within the spot. This intensity variation is found to be comparable with the change in intensity from one spot to another. The penumbral intensity is found to be independent of spot size in the sample considered.
The penumbra model of Kjeldseth Moe and Maltby (1969) with δθ = 0.055 is supported by the measurements.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Birkle, K. and Mattig, W.: 1965, Z. Astrophys. 60, 264.
Bode, G.: 1965, Die kontinuerliche Absorption von Sternatmosphären in Abhähngigkeit von Druck, Temperatur und Elementhäufigkeiten, Kiel.
Bray, R. J. and Loughhead, R. E.: 1964, Sunspots, Chapman and Hall, London.
Kjeldseth Moe, O. and Maltby, P.: 1969, Solar Phys. 8, 275.
Maltby, P. and Mykland, N.: 1969, Solar Phys. 8, 23.
Maltby, P. and Staveland, L.: 1971, Solar Phys. 18, 443.
Maltby, P. and Staveland, L.: 1972, Inst. Theor. Astrophysics Report No. 33.
Makita, M. and Morimoto, M.: 1960, Publ. Astron. Soc. Japan 12, 63.
Schleicher, H. and Schröter, E. H.: 1971, Solar Phys. 17, 31.
Wöhl, H., Wittmann, A., and Schröter, E. H.: 1970, Solar Phys. 13, 104.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Maltby, P. Observations of the intensity of the penumbra of sunspots. Sol Phys 26, 76–82 (1972). https://doi.org/10.1007/BF00155106
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00155106