Orbital elements for double stars of Population II. The system HD 29907*
Lund Observatory, Box 43, S-221 00 Lund, Sweden
Send offprint request to: H. Lindgren
Accepted: 14 February 1996
For HD 29907 results are presented from radial-velocity monitoring and from photometric observations on the uvby system. The object is a binary system at a distance of around 50 parsecs from the sun. The primary component is a G2 VI star. The secondary component remains unidentified. The absolute visual magnitude of the primary component is MV=+6.6, and the effective temperature and abundance of heavy elements are given by and [Fe/H]=-1.7, respectively. The V magnitude appears variable with a range of at least 0.12 magnitudes. Colour indices appear stable. The system has a radial velocity of , an orbital period of 29.9 days and an eccentricity of 0.41. The total space velocity with respect to the galactic center is 340 and the object approaches escape velocity.
Key words: stars: binaries: spectroscopic / stars: kinematics / stars: Population II / stars: subdwarfs / stars: HD 29907
© European Southern Observatory (ESO), 1996