Uvby light curves of the eclipsing binary system V2154 Cyg

This paper presents complete uvby light curves for the recently discovered eclipsing binary system V2154 Cyg. Additional Crawford Hβ data were also obtained. Three times of primary minima and two secondary minima are determined. An improved orbital period is found to be 2d.6306312. A detailed photometric analysis is made using the EBOP code. This eclipsing binary is probably one of the components of a much wider double star, forming altogether a triple system. The results show that the eclipsing pair is a detached system with two late-type stars very different in size. Masses of about M1 = 1.4 M⊙ and M2 = 0.8 M⊙ are inferred for the components by using stellar evolution models. The total mass of the probable triple system is estimated to be of about 3.5 M⊙, leading to a minimum orbital period of about 140 yr for the visual pair.