Light Curve Solutions of Ten Eccentric Kepler Binaries, Three of them with Tidally Induced Humps

TL;DR

This study analyzes light curves of ten eccentric Kepler binaries, revealing deviations from empirical relations and identifying tidally induced humps, with detailed parameter solutions and insights into stellar interactions.

Contribution

First detailed light curve solutions for ten eccentric Kepler binaries, highlighting deviations from circular binary relations and analyzing tidally induced features.

Findings

Components of some binaries do not follow circular binary relations.

Identified tidally induced humps in three binaries.

Derived dependence of hump amplitude on stellar parameters.

Abstract

We carried out light curve solutions of ten detached eclipsing eccentric binaries observed by Kepler. The formal errors of the derived parameters from the light curve solutions are below 1%. Our results give indications that the components of the eccentric binaries (especially those with mass ratios below 0.5) do not follow precisely the empirical relations between the stellar parameters derived from the study of circular-orbit binaries. We found the following peculiarities of the targets: (a) the components of KIC 9474969 have almost the same temperatures while their radii and masses differ by a factor around 2.5; (b) KIC 6949550 reveals semi-regular light variations with an amplitude of 0.004 and a period around 7 d which are modulated by long-term variations; (c) KIC 6220470, KIC 11071207, and KIC 9474969 exhibit tidally induced 'hump' around the periastron. These are the targets with the biggest relative radii of our sample. We derived the dependence of the hump amplitude on the relative stellar radii, eccentricity, and mass ratio of eccentric binary consisting of MS stars.