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Continuum Observations and Empirical Models of the Thermal Structure of Sunspots

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Sunspots: Theory and Observations

Part of the book series: NATO ASI Series ((ASIC,volume 375))

Abstract

Intensity observations of sunspot umbrae and penumbrae in the visible and infrared are reviewed. The continuum intensity in the darkest part of the umbra and the average penumbral intensity are known with relatively high accuracy in large sunspots. With the aim of understanding conflicting observations of umbral dots it is suggested that the umbral core is nearly free of umbral dots, and that an umbral core only occurs in sunspots above a certain size.

The present status of semi-empirical models of the temperature stratification in umbrae and penumbrae is discussed and the need for extending the model calculations to more than one dimension is pointed out.

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Authors and Affiliations

  1. Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, 0315, Oslo, Norway

    P. Maltby

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  1. P. Maltby
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Editors and Affiliations

  1. Department of Mechanical Engineering, Department of Physics and Astronomy and C.E.K. Mees Observatory, University of Rochester, Rochester, NY, USA

    John H. Thomas

  2. Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK

    Nigel O. Weiss

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© 1992 Kluwer Academic Publishers

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Maltby, P. (1992). Continuum Observations and Empirical Models of the Thermal Structure of Sunspots. In: Thomas, J.H., Weiss, N.O. (eds) Sunspots: Theory and Observations. NATO ASI Series, vol 375. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-2769-1_4

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  • DOI: https://doi.org/10.1007/978-94-011-2769-1_4

  • Publisher Name: Springer, Dordrecht

  • Print ISBN: 978-94-010-5229-0

  • Online ISBN: 978-94-011-2769-1

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