Absolute parameters of the eclipsing binary V821 Cas from UBVRI light curves and radial velocities

• Published in: Monthly notices of the Royal Astronomical Society Vol. 395; no. 3; pp. 1649 - 1656
• Main Authors: Çakırlı, Ö., İbanoǧlu, C., Bilir, S., Sipahi, E.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 21-05-2009; Wiley-Blackwell; Oxford University Press
• Subjects: Astronomy; binaries: close; binaries: eclipsing; binaries: general; binaries: spectroscopic; Double stars; Earth, ocean, space; Exact sciences and technology; Spectrum analysis; Star & galaxy formation; stars: individual: V821 Cas; Velocity; binaries: close; binaries: eclipsing; binaries: general; binaries: spectroscopic; stars: individual: V821 Cas; Eclipsing binary stars; Light curves; Stellar evolution; Star models; Cross correlations; Theoretical model; Close binary stars; Radial velocity; Spectroscopical observation; Age; Spectroscopic binary stars
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1111/j.1365-2966.2009.14651.x

We present UBVRI photometric measurements and spectroscopic observations of the double-lined eclipsing binary V821 Cas. The radial velocities were obtained by means of the cross-correlation technique. Simultaneous analyses of the multiband light curves and RVs give the absolute parameters for the stars as: and . An analysis of the O–C residuals yielded an apsidal motion in the binary at a rate of , corresponding to an apsidal period of U= 118 ± 19 yr. Subtracting the relativistic contribution, we find that log k2obs=−2.590 which is in agreement with the value predicted by theoretical models. Comparison with current stellar evolution models gives an age of 5.6 × 108 yr for the system.