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

ÇAKIRLI Ö., Ibanoglu C., Bilir S. , SİPAHİ E.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, cilt.395, sa.3, ss.1649-1656, 2009 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 395 Konu: 3
  • Basım Tarihi: 2009
  • Doi Numarası: 10.1111/j.1365-2966.2009.14651.x
  • Sayfa Sayıları: ss.1649-1656


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: M-1 = 2.05 +/- 0.07M(circle dot); M-2 = 1.63 +/- 0.06M(circle dot); R-1 = 2.31 +/- 0.03R(circle dot); R-2 = 1.39 +/- 0.02R(circle dot); T-eff1 = 9400 +/- 400 K and T-eff2 = 8 600 +/- 400 K. An analysis of the O-C residuals yielded an apsidal motion in the binary at a rate of omega = 0 degrees.0149 +/- 0 degrees.0023 cycle(-1), corresponding to an apsidal period of U = 118 +/- 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 x 10(8) yr for the system.