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arXiv · 0902.3083

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

O. Cakirli·C. Ibanoglu·S. Bilir·E. Sipahi
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Abstract

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 multi-band light curves and RVs give the absolute parameters for the stars as: M$_1$=2.05$\pm$0.07 M$_{\odot}$, M$_2$=1.63$\pm$0.06 M$_{\odot}$, R$_1$=2.31$\pm$0.03 R$_{\odot}$, R$_2$=1.39$\pm$0.02 R$_{\odot}$, T$_{eff_1}$=9 400$\pm$400 K, and T$_{eff_2}$=8 600$\pm$400 K. Analysis of the O-C residuals yielded an apsidal motion in the binary at a rate of $\dotω$=0$^{\degr}$.0149$\pm0^{\degr}$.0023 cycle$^{-1}$, corresponding to an apsidal period of U=118$\pm$19 yr. Subtracting the relativistic contribution we find that $\log k_{2obs}$=-2.590 which is in agreement with the value predicted by theoretical models. Comparison with current stellar evolution models gives an age of $5.6\times10^{8}$ yr for the system.

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O. Cakirli, C. Ibanoglu, S. Bilir, E. Sipahi. 2009-02-18. Absolute parameters of the eclipsing binary V821 Cas from UBVRI light curves and radial velocities. https://doi.org/10.1111/j.1365-2966.2009.14651.x

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