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High Resolution Spectroscopy of Six New Extreme Helium Stars

Published online by Cambridge University Press:  12 April 2016

U. Heber
Affiliation:
Institut für Theoretische Physik und Sternwarte , der Universitat KielOlshausenstr. 40, 2300 Kiel, F.R.G.
G. Jonas
Affiliation:
Institut für Theoretische Physik und Sternwarte , der Universitat KielOlshausenstr. 40, 2300 Kiel, F.R.G.
J.S. Drilling
Affiliation:
Institut für Theoretische Physik und Sternwarte , der Universitat KielOlshausenstr. 40, 2300 Kiel, F.R.G. Department of Physics and AstronomyLouisiana State UniversityBaton Rouge, LA 70803-4001, U.S.A.

Abstract

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High resolution spectra of six newly discovered extreme helium stars are presented. LSS 5121 is shown to be a spectroscopical twin of the hot extreme helium star HD 160641. A preliminary LTE analysis of LSS 3184 yielded an effective temperature of 22000 K and a surface gravity of log g = 3.2. Four stars form a new subgroup, classified by sharp-lined He I spectra and pronounced 0 II spectra, and it is conjectured that these lie close to the Eddington limit. The whole group of extreme helium stars apparently is inhomogenous with respect to luminosity to mass ratio and chemical composition.

Type
III Hot Extreme Helium Stars
Copyright
Copyright © Reidel 1986

References

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