A photometric study of eclipsing binary V351 Pegasi

Abstract

Photoelectric BVR light curves of the recently discovered eclipsing binary V351 Peg were studied for the first time to derive the physical parameters of the system. The light curves were obtained at the TÜBİTAK National Observatory (TUG) during three nights in August 2003. The solutions made by using Djurašević's inverse-problem method describe the V351 Peg system as an overcontact configuration (fover ∼ 21%) with a very small temperature difference between the components (δT = T h-Tc ∼ 21 K). Having in mind large difference in their masses, this suggests a good thermal contact between the components, i.e. a significant energy transfer from the more massive primary onto the less massive secondary. The bright area on the less massive star, near the neck region of the common envelope, can be taken as a consequence of this energy exchange between the components. Roche model with this bright active region on the less massive star successfully fits the observations. The relatively small amplitude of light curves arises from partial eclipse caused by the low orbital inclination (i ∼ 63°). The stellar temperatures (Th ∼ 7580 K and Tc ∼ 7560 K) and the estimated values of the gravity-darkening exponents (βh ∼ 0.20 and β c ∼ 0.18) indicate that there is a mixture of radiative and convective transport of energy. © 2004 Elsevier B.V. All rights reserved.