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

TL;DR

This study presents multi-color photometry and a comprehensive period analysis of the eclipsing binary V1073 Cyg, revealing its shallow contact nature, complex period variations, and potential third companion influence.

Contribution

It provides detailed light curve analysis and long-term period change study, including the first combined O-C analysis spanning 119 years for V1073 Cyg.

Findings

V1073 Cyg is a shallow contact binary with a fill-out factor of 0.124.

The orbital period is decreasing at a rate of approximately 1.04×10^{-10} days per cycle.

A cyclic period variation with an 82.7-year period suggests magnetic activity or a third body.

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 $f=0.124(\pm0.011)$. 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 $\dot P=-1.04(\pm0.18)\times 10^{-10}$ $days\cdot{cycle}^{-1}$, and with the period decrease, V1073 Cyg will evolve to deep contact stage. The cyclic variation with a period of $P_3=82.7(\pm3.6) years$ and an amplitude of $A=0.028(\pm0.002) day$ 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 $M_3({i'}=90^{\circ})=0.511M_\odot$.