VZ CVn: a close binary system with γ Doradus-like variations

Abstract

We present new photometric two-colour observations of the double-lined close binary star VZ CVn. Combining two data sets obtained in 1971-72 and in 2006, the physical parameters of both components were derived. After removing the light variations due to the eclipses and proximity effects, a periodic variation in the more massive component with a dominant period of 1.068 76 d could be detected in the first photometric data set. In accordance with its position on the Hertzsprung-Russell diagram and both its pulsation period and pulsation constant of 0.62 d, the primary component of VZ CVn should be an excellent γ Doradus candidate. The less massive secondary component seems to have smaller radius with respect to its mass. Both components appear to have lower luminosities with respect to their masses; hence, their radiative properties seem to be different. The evolutionary status of the components is also discussed.The photometric observations were obtained between 2006 May 02 and 30 with the 35-cm MEADE telescope at Ege University Observatory. We used SSP-5 type photometer and Johnson B and V filters. The comparison and check stars are BD +29 • 2417 (V = 8.77 mag, B − V = 0.492 mag) and BD +29 • 2409 (V = 9.71 mag, B − V = 0.34 mag), respectively, which were also used in the

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