Forum Springer Astron. Astrophys.
Forum Whats New Search Orders

Astron. Astrophys. 345, 855-868 (1999)

Table of Contents
Available formats: HTML | PDF | (gzipped) PostScript

Search for forced oscillations in binaries

III. Improved elements and the detection of line-profile variability of the B4V + A6V: system AR Cassiopeiae

D.E. Holmgren *  1, P. Hadrava 1, P. Harmanec 1, P. Eenens 2, L.J. Corral 3, S. Yang[FORMULA]  4, H. Ak 5 and H. Boi 6

1 Astronomický ústav, Akademie v d eské Republiky, CZ-251 65 Ond ejov, Czech Republic
(holmgren@brandonu.ca; had(hec)@sunstel.asu.cas.cz)
2 Departamento de Astronomia, Universidad de Guanajuato, Apartado 144, 36000 Guanajuato, GTO, Mexico (eenens@carina.astro.ugto.mx)
3 Instituto de Astrofísica de Canarias, c/Vía Lactea s/n, E-38200 La Laguna, Spain (lcorral@iac.es)
4 Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Victoria, B.C., V8W 3P6, Canada (yang@beluga.phys.uvic.ca)
5 Ankara University, Science Faculty, Astronomy and Space Science Department, Tandoan, 06100 Ankara, Turkey
6 Hvar Observatory, Faculty of Geodesy, Zagreb University, Ka ieva 26, 10000 Zagreb, Croatia (hbozic@geodet.geof.hr)

Received 11 June 1998 / Accepted 9 March 1999


An analysis of a new and extensive set of spectroscopic observations of the early-type binary system AR Cas , based also on spectral disentangling, has led to the discovery of the spectrum of the secondary star and of line-profile variations of the B4V primary star. A revised spectroscopic orbit based on these and published data is presented. We also present new photometric data, which have allowed us to improve the solution of the light curve and demonstrate the presence of apsidal motion. Determination of the basic physical parameters of the binary has allowed us to conclude that the system combines the main-sequence primary with an A6V: secondary, possibly an Am star. The consistency of our model of AR Cas is documented by a comparison of model atmosphere flux profiles with the profiles recovered from the spectral disentangling. Analysis of the He I 667.8 nm line indicates that line profile variability is present, and that these variations may be periodic.

Key words: stars: binaries: spectroscopic – stars: fundamental parameters – stars: individual: AR Cas

* Guest investigator, Dominion Astrophysical Observatory, Victoria, BC, Canada

Send offprint requests to: D. Holmgren, Department of Physics and Astronomy, Brandon University, Brandon, Manitoba, R7A 6A9, Canada

© European Southern Observatory (ESO) 1999

Online publication: April 28, 1999