Multi-color light curves and orbital period research of eclipsing binary V1073 Cyg

Abstract

New Multi-color $B$ $V$ $R_c$ $I_c$ photometric observation are presented for W UMa type eclipsing binary V1073 Cyg. The multi-color light curves analysis with the Wilson-Devinney(W-D) procedure acquired the absolute parameters of this system, showing that V1073Cyg is a shallow contact binary system with fill-out factor $f=0.124(\pm 0.011)$. We collected all available times of light minima spanning 119 years including CCD data to construct the O-C curve and made detailed O-C analysis. The O-C diagram shows that the period change is complex. There exist a long-term continuous decrease and a cyclic variation. The period is decreasing at a rate of $\dot{P}=-1.04(\pm 0.18)\times 10^{-10}$ $days\cdot {cycle}^{-1}$, and with the period decrease, V1073 Cyg will evolve to deep contact stage. The cyclic variation with a period of $P_3=82.7(\pm 3.6)years$ and an amplitude of $A=0.028(\pm 0.002)day$ may be explained by the magnetic activity of one or both components or the light travel time effect (LTTE) caused by a distant third companion with $M_3(i^{\prime }=90^{\circ })=0.511M_{\odot }$.

15 pages, 5 figures