The authors have assembled a sample of 42 W Ursae Majoris binary systems (21 W-type, 21 A-type) whose light curves have all been solved by means of the Wilson & Devinney method. The masses, radii and luminosities have been derived assuming the global physical properties of a system are the same as for an analogous detached one, and therefore without any constraint on the physical parameters of the primary star. The main results of this procedure are: (i) the discovery of a substantial continuity of the physical properties from W-type to A-type, suggesting a scenario in which almost all A-type systems are the evolved counterparts of W-types; (ii) the existence of an inhomogeneous group probably evolved into contact from a detached configuration. This second group has no evolutionary link with the RS CVn-like systems, which seemed at first to be suitable candidates as parent stars. An upper limit for the primary mass of unevolved objects is derived.

General properties of W Ursae Majoris systems

L. Milano
Membro del Collaboration Group
;
G. Russo
Membro del Collaboration Group
1985

Abstract

The authors have assembled a sample of 42 W Ursae Majoris binary systems (21 W-type, 21 A-type) whose light curves have all been solved by means of the Wilson & Devinney method. The masses, radii and luminosities have been derived assuming the global physical properties of a system are the same as for an analogous detached one, and therefore without any constraint on the physical parameters of the primary star. The main results of this procedure are: (i) the discovery of a substantial continuity of the physical properties from W-type to A-type, suggesting a scenario in which almost all A-type systems are the evolved counterparts of W-types; (ii) the existence of an inhomogeneous group probably evolved into contact from a detached configuration. This second group has no evolutionary link with the RS CVn-like systems, which seemed at first to be suitable candidates as parent stars. An upper limit for the primary mass of unevolved objects is derived.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11588/892421
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact