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Astrophysics and Space Science

, Volume 189, Issue 2, pp 237–262 | Cite as

Evolutionary state of W UMa-type systems

  • H. Rovithis-Livaniou
  • P. Rovithis
  • O. Bitzaraki
Article

Abstract

The evolutionary status of a sample of 31 W UMa-type systems (20 of W, 9 of A, and 2 of A/W sub-class) is examined and discussed on the basis of their positions in the H-R, mass-radius and mass-luminosity diagrams. The absolute elements of these systems have been evaluated by use of their spectroscopic and photometric data as they were found in the literature. Since different analysis methods have been used by the various investigators this gives the opportunity to make different H-R, mass-radius and mass-luminosity diagrams, according to the method used, and compare the results.

Moreover, from the spectral type-period diagram of those systems that have spectral types from O to G2 it was found that all of them lie in the evolved region. Finally, the log (Ll/Ls) log (Ml/Ms) diagrams are presented and discussed.

Keywords

Evolutionary State Spectral Type Photometric Data Absolute Element 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • H. Rovithis-Livaniou
    • 1
  • P. Rovithis
    • 1
  • O. Bitzaraki
    • 1
  1. 1.Department of PhysicsUniversity of AthensAthensGreece

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