Evolutionary state of W UMa-type systems

Autor: H. Rovithis-Livaniou, Peter Rovithis, O. M. Bitzaraki
Rok vydání: 1992
Předmět:
Zdroj: Astrophysics and Space Science. 189:237-262
ISSN: 1572-946X
0004-640X
DOI: 10.1007/bf00643128
Popis: 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 (L l/L s) log (M l/M s) diagrams are presented and discussed.
Databáze: OpenAIRE
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