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High Temperature Structure in Cool Binary Stars

Published online by Cambridge University Press:  12 April 2016

A.K. Dupree ,
N.S. Brickhouse  and
G.J. Hanson
A.K. Dupree
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138USA
N.S. Brickhouse
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138USA
G.J. Hanson
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138USA

Abstract

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Strong high temperature emission lines in the EUVE spectra of binary stars containing cool components (Alpha Aur [Capella], 44ι Boo, Lambda And, and VY Ari) provide the basis to define reliably the differential emission measure of hot plasma. The emission measure distributions for the short-period (P ≤ 13 d) binary systems show a high temperature enhancement over a relatively narrow temperature region similar to that originally found in Capella (Dupree et al. 1993). The emission measure distributions of rapidly rotating single stars 31 Com and AB Dor also contain a local enhancement of the emission measure although at different temperatures and width from Capella, suggesting that the enhancement in these objects may be characteristic of rapid rotation of a stellar corona. This feature might be identified with a (polar) active region, although its density and absolute size are unknown; in the binaries Capella and VY Ari, the feature is narrow and it may arise from an interaction region between the components.

Type
III. Coronae of Cool Stars
Information
International Astronomical Union Colloquium , Volume 152: Astrophysics in the Extreme Ultraviolet , 1996 , pp. 141 - 145
Copyright
Copyright © Kluwer 1996

References

Brickhouse, N.S., Raymond, J.C., & Smith, B.W. 1995, New Model of Iron Spectra in the Extreme Ultraviolet and Application to SERTS and EUVE Observations of a Solar Active Region and Capella, ApJS, 97, 551 Google Scholar
Dupree, A.K., Brickhouse, N.S., Doschek, G.A., Green, J.C., & Raymond, J.C. 1993, The Extreme Ultraviolet Spectrum of Alpha Aurigae Capella, ApJ, 418, L41–L44 Google Scholar
Dupree, A.K., Brickhouse, N.S., Doschek, G.A., Hanson, G.J., & Raymond, J.C. 1994, EUVE Spectra of Alpha Aurigae Capella, at Different Phases, BAAS, 26, 864 Google Scholar
Dupree, A.K., Brickhouse, N.S., & Hanson, G.J. 1995, Inhomogeneity of Coronal Structures in Capella, in prereparationGoogle Scholar
Fekel, F.C., Moffett, T.J., & Henry, G.W. 1986, A Survey of Chromospherically Active Stars, ApJS, 60, 551 Google Scholar
Hanson, G.J., Brickhouse, N.S., & Dupree, A.K. 1995, EUVE Spectra of Lambda Andromedae and Sigma Geminorum, ApJ, submittedGoogle Scholar
Klmble, R. Plus, 13 AUTHORS 1993, Extreme Ultraviolet Observations of G191-B2B and the Local Interstellar Medium with the Hopkins Ultraviolet Telescope, ApJ, 404, 663 Google Scholar
Pilachowski, C.A., & Sowell, J.R. 1992, The Lithium Abundance of the Capella Giants, AJ, 103, 1668 Google Scholar
Wallerstein, G., BoHm-ViTense, E., Vanture, A.D., & Gonzalez, G. 1994, The Lithium Content and Other Properties of F2-G5 Giants in the Hertzsprung Gap, AJ, 107, 2211 Google Scholar