BEER analysis of Kepler and CoRoT light curves. V. eBEER: Extension of the Algorithm to Eccentric Binaries

TL;DR

This paper introduces eBEER, an extension of the BEER model, for rapid detection of eccentric binary systems in Kepler and CoRoT light curves, validated through spectroscopic follow-up.

Contribution

The paper develops and validates eBEER, a new harmonic series-based method for identifying non-eclipsing eccentric binaries in light curves.

Findings

eBEER successfully identified non-eclipsing eccentric binaries in Kepler data.

Spectroscopic follow-up confirmed the binary nature of selected candidates.

eBEER parameters closely match detailed PHOEBE models.

Abstract

We present an extension of the BEER model for eccentric binaries - eBEER, approximating the BEaming, Ellipsoidal and Reflection effects by harmonic series of the Keplerian elements of their orbit. As such, it can be a tool for fast processing of light curves for detecting non-eclipsing eccentric binary systems. To validate the applicability of the eccentric model and its approximations, we applied eBEER to the Kepler light curves, identified a sample of bright non-eclipsing binary candidates, and followed three of them with the Wise observatory eShel spectrograph. After confirming the three systems are indeed radial-velocity (RV) binaries, we fitted the light curves and the RV data with PHOEBE, a detailed numerical light-curve and RV model, and showed that the PHOEBE derived parameters are similar to those obtained by the eBEER approximation.