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Empirical Scaling Laws for Coronal Heating

Published online by Cambridge University Press:  04 August 2017

Leon Golub*
Affiliation:
Smithsonian Astrophysical Observatory Cambridge, MA 02138, USA

Abstract

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We review the origins and uses of scaling laws in studies of stellar outer atmospheres, with particular emphasis on the properties of coronal loops. The evidence for a fundamental structuring of the Solar corona is reviewed and a discussion of thermodynamic scaling laws is presented. In order to intercompare different theories for coronal formation and heating, it is necessary to recast the theories in terms of observable quantities. As an example, we present a discussion of magnetic field-related heating and scaling laws which can be obtained relating coronal pressure, temperature and magnetic field strength; available data are shown to be consistent with scaling laws obtained in this way. However, some parameters of the theory must be treated as adjustable at the present time and it is necessary to examine data from other stars in order to determine whether these are true parameters in coronal heating. We examine some of the difficulties involved in using unresolved stellar data when dealing with loop atmospheres, by first treating the Sun as an unresolved source. Using the detailed observations now available we examine the limits of applicability of single-loop models. The possibilities and limits of stellar data are then discussed.

Type
IV. The Role of Magnetic Fields in the Structure and Energy Balance of Stellar Atmospheres
Copyright
Copyright © Reidel 1983 

References

Biermann, L.: 1946, Naturwissenschaften 88, p. 118.CrossRefGoogle Scholar
Billings, D.E. and Saito, K.: 1964, Astrophys. J. 140, p. 760.Google Scholar
Craig, I.J.D., McClymont, A.N., and Underwood, J.H.: 1978, Astron. Astrophys. 70, p. 1.Google Scholar
Galeev, A.A., Rosner, R., Serio, S., and Vaiana, G.S.: 1980, Astrophys. J. 248, p. 201.Google Scholar
Golub, L.: 1980, Phil. Trans. Royal Soc. London A, 297, p. 595.Google Scholar
Golub, L.: 1982, in “Proc. 2nd Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun”, eds. Giampapa, M.S. and Golub, L. (Smithsonian Special Report No. 392), p. 39.Google Scholar
Golub, L., Maxson, C.W., Rosner, R., Serio, S., and Vaiana, G.S.: 1980, Astrophys. J. 238, p. 343.CrossRefGoogle Scholar
Ionson, J.A.: 1978, Astrophys. J. 226, p. 650.CrossRefGoogle Scholar
Kuperus, M., Ionson, J.A., and Spicer, D.S.: 1981, Ann. Rev. Astron. Astrophys. 19, p. 7.CrossRefGoogle Scholar
Maxson, C.W. and Vaiana, G.S.: 1977, Astrophys. J. 215, p. 919.CrossRefGoogle Scholar
McIntosh, P.S., Krieger, A.S., Nolte, J.T., and Vaiana, G.S.: 1976, Solar Phys. 49, p. 57.CrossRefGoogle Scholar
Osterbrock, D.E.: 1961, Astrophys. J. 134, p. 347.CrossRefGoogle Scholar
Pallavicini, R.P., Serio, S., and Vaiana, G.S.: 1977, Astrophys. J. 216, p. 108.CrossRefGoogle Scholar
Parker, E.N.: 1974, Astrophys. J. 191, p. 245.CrossRefGoogle Scholar
Rosner, R., Golub, L., Coppi, B., and Vaiana, G.S.: 1978, Astrophys. J. 222, p. 317.CrossRefGoogle Scholar
Rosner, R., Tucker, W.H., and Vaiana, G.S.: 1978, Astrophys. J. 220, p. 643.CrossRefGoogle Scholar
Schwarzschild, M.: 1948, Astrophys. J. 107, p. 1.CrossRefGoogle Scholar
Serio, S., Peres, G., Vaiana, G.S., Golub, L., and Rosner, R.: 1981, Astrophys. J. 243, p. 288.CrossRefGoogle Scholar
Vaiana, G.S., Krieger, A.S., and Timothy, A.F.: 1973, Solar Phys. 32, p. 81.CrossRefGoogle Scholar
Vaiana, G.S., Krieger, A.S., and Van Speybroeck, L.P.: 1970, in “Solar Magnetic Fields”, ed. Howard, R., IAU Symp. 43, p. 397.CrossRefGoogle Scholar
Van Speybroeck, L.P., Krieger, A.S., and Vaiana, G.S.: 1970, Nature 227, p. 818.CrossRefGoogle Scholar
Vesecky, J.F., Antiochos, S.K., and Underwood, J.H.: 1979, Astrophys. J. 233, p. 987.CrossRefGoogle Scholar