Light curve solutions of the eclipsing eccentric binaries KIC 8111622, KIC 10518735, KIC 8196180 and their out-of-eclipse variability

TL;DR

This study analyzes light curves of four eccentric eclipsing binaries from Kepler data, revealing stellar parameters, eclipse types, and out-of-eclipse variability, including tidally-induced features and star spots, confirming theoretical models.

Contribution

It provides detailed orbital and stellar parameters for three eccentric binaries and identifies out-of-eclipse phenomena consistent with theoretical predictions.

Findings

KIC 8196180 is a heartbeat star with tidally-induced features.

KIC 8111622 shows short-period light variations from star spots.

KIC 8196180 exhibits out-of-eclipse variability likely due to star spots.

Abstract

We determined the orbits and stellar parameters of three eccentric eclipsing binaries by light curve solutions of their Kepler data. KIC 8111622 and KIC 10518735 undergo total eclipses while KIC 8196180 reveals partial eclipses. The target components are G and K stars, excluding the primary of KIC 8196180 which is early F star. KIC 8196180 reveals well-visible tidally-induced feature at periastron, i.e. it is an eclipsing heartbeat star. The characteristics of the observed periastron feature (shape, width and amplitude) confirm the theoretical predictions. There are additional out-of-eclipse variations of KIC 8196180 with the orbital period which may be explained by spot activity of synchronously rotating component. Besides worse visible periastron feature KIC 811162 exhibits small amplitude light variations whose period is around 2.3 times shorter than the orbital one. These oscillations were attributed to spot(s) on asynchronously rotating component.