Astron. Astrophys. Suppl. Ser.
Volume 123, Number 2, June I 1997
|Page(s)||209 - 218|
|Published online||15 June 1997|
Constraints on its physical parameters
Department of Geosciences and Astronomy, University of Oulu, Linnanmaa, P.O. Box 333, FIN–90571 Oulu, Finland
Corresponding author: Send offprint request to: R. Duemmler; e-mail: Rudolf.Duemmler@oulu.fi
Accepted: 25 September 1996
26 high quality radial velocity measurements of the RS CVn star σ Gem taken in 1993, 1994, and 1995 are used in combination with older measurements to fit a new radial velocity curve. Essentially, the orbital parameters given by Bopp & Dempsey (1989) are confirmed. However, the orbit turns out to be circular. σ Gem is known as a single–lined binary, and also in the new spectra no trace of the secondary is found. However, combining the orbital with rotational parameters, constraints on the fundamental parameters can be found: the inclination, the radius and the two masses. The inclination is high; the mass of the primary seems to be normal for a K1 giant, its radius, however, seems to be too small.
Key words: stars: spectroscopic / stars: fundamental parameters / binaries: stars individual: σ Gem
Table 1 is also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (220.127.116.11) or via http://cdsweb.u-strasbg.fr/Abstract.html
© European Southern Observatory (ESO), 1997