Photometric study for the short period contact binary V724 And

We present the new light curve synthesis and orbital period change analysis of V724 And. We found that it is a W-subtype contact binary system with a mass ratio of q = 2.31 and a fill-out factor of f = 10.8%. The weak O’Connell effect can be explained by a cool star-spot on the more massive component star. By analyzing orbital period changes, it is found that the target displays a secular period decrease superimposed on a cyclic oscillation. The orbital period decreases at a rate of dp/dt = −4.13 × 10⁻⁸ d yr⁻¹, which can be explained by the mass transfer from the more massive one to the less massive component. The new discovery suggests that the semi-amplitude and period of the cyclic variation are A = 0.0013 d and P = 10.54 yr, respectively, which implies that V724 And is a possibly triple system. The minimum mass of the tertiary companion is estimated as M${}_{3min}$ = 0.054 M${}_{\odot }$, which plays an important role during the formation and evolution of the central binary system.