First investigation of eclipsing binary KIC 9026766: analysis of light curve and periodic changes

TL;DR

This study analyzes the light curve and period variations of the short-period eclipsing binary KIC 9026766, revealing potential third-body effects and stellar activity influences through detailed modeling and O-C analysis.

Contribution

First detailed analysis of KIC 9026766 combining light curve modeling and period change investigation, including potential third-body detection and stellar spot activity assessment.

Findings

Orbital period change suggests a third body with minimum mass of 0.029 solar masses.

Detected periodic signals possibly due to spot motion or background star effects.

Calculated stellar parameters and eclipse luminosity ratios.

Abstract

Abstract We investigate a short-period W UMa binary KIC 9026766 with an orbital period of 0.2721278 days in the Kepler field of view. By using an automated q-search for the folded light curve and producing a synthetic light curve for this object based on the PHOEBE code, we calculate the fundamental stellar parameters. We also analyze the O-C curve of the primary minima. The orbital period changes can be attributed to the combination of an upward quadratic function and light-travel time effect due to a possible third body with a minimum mass of 0.029 solar mass and an orbital period of 972.5866 days. The relative luminosity of the primary and secondary eclipses (Min I Min II) is calculated. The periodogram of the residuals of the LTT effect, and Min I Min II show peaks with the same period of 0.8566 days. The background effect of two nearby stars on our target is the possible reason for this signal. By considering the amplitudes and periods of the remaining signals in the OC curve of minima, spot motion is possible.