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Extensions of the Wilson-Bappu Effect Among Very Luminous Stars

Published online by Cambridge University Press:  14 August 2015

Robert E. Stencel*
Affiliation:
NASA/Johnson Space Center, Houston Texas

Extract

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Twenty years ago, Wilson and Bappu (1957) published their observational correlation of MV and the logarithm of the full width at half maximum of the CaII K-line central emission for G, K and M stars. The technique was stated to have ± 0m.5 accuracy, while a tabulation of MV(K) by Wilson (1976) suggests the error may only be ± 0m.3. This accuracy makes the approach valuable for late-type supergiants since other methods suffer from comparable errors. However, for F through M supergiants (Ia, 0), circumstellar absorption obscures the chromospheric K-line core emission and excludes such objects from the Wilson-Bappu correlation. I report here on a new class of emission lines in late-type giant and supergiant spectra that exhibit MV correlated widths, yet are detectable among the brightest stars.

Type
Part I: Fundamentals of the HR Diagram
Copyright
Copyright © Reidel 1978 

References

Deutsch, A. (1960). In Stars and Stellar Systems, Vol. VI, Stellar Atmospheres, Greenstein, J., ed., Univ. of Chicago Press, Chicago, p. 556.Google Scholar
Fosbury, R. (1971). Mon. Not. Roy. Astron. Soc. 155, 7P.Google Scholar
Kondo, Y., Morgan, T. and Modisette, J. (1976a). Astrophys. J. 207, 167.CrossRefGoogle Scholar
Kondo, Y., Morgan, T. and Modisette, J. (1976b). Astrophys. J. 209, 489.CrossRefGoogle Scholar
Sandage, A. and Tammann, G. (1974). Astrophys. J. 191, 603.Google Scholar
Sargent, W. (1961). Astrophys. J. 134, 142.Google Scholar
Sargent, W. (1965). Observatory 85, 33.Google Scholar
Stencel, R. (1977a). Astrophys. J. 215, 176.CrossRefGoogle Scholar
Stencel, R. (1977b). , Univ. Michigan. Univ. Microfilms, Ann Arbor, Order No. 77–26, 369.Google Scholar
Wilson, O. (1976). Astrophys. J. 205, 823.CrossRefGoogle Scholar
Wilson, O. and Bappu, V. (1957). Astrophys. J. 125, 661.CrossRefGoogle Scholar