Astrophysics

Abstract We present time-series CCD photometry of V551 Aur, an eclipsing binary located in the open cluster NGC 2126 that shows δ Scuti-like pulsations. Complete covered light curves in the B and V bands were obtained with high-precision over nine nights. Based on them, a revised orbital period and the first photometric solutions were determined. Our eclipsing light-curve synthesis reveals a detached configura-tion for the binary system with a mass-ratio of about 0.73, and the mean density of the pulsating primary component was deduced to be about (0.532±0.005)ρ⊙. A fre-quency analysis of the eclipse-subtracted light curve yields two reliable frequencies at f1=7.727013(c/d) and f2=15.45403(c/d), respectively. With the help of the derived mean density, mode identification was performed. The result suggests that the primary component of V551 Aur is very probably g-mode oscillations