A transiting companion to the eclipsing binary KIC002856960

¹ Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK
e-mail: darmstrong25@qub.ac.uk
² Astrophysics Research Centre, School of Mathematics & Physics, Queen’s University Belfast, University Road, Belfast BT7 1NN, UK
³ Isaac Newton Group of Telescopes, Apartado de Correos 321, 38700 Santa Cruz de la Palma, Canary Islands, Spain
⁴ Department of Physics & Astronomy, Vanderbilt University, Nashville, TN 37235, USA

Received: 25 April 2012
Accepted: 17 August 2012

Abstract

We present an early result from an automated search of Kepler eclipsing binary systems for circumbinary companions. An intriguing tertiary signal has been discovered in the short period eclipsing binary KIC002856960. This third body leads to transit-like features in the light curve occurring every 204.2 days, while the two other components of the system display eclipses on a 6.2 h period. The variations due to the tertiary body last for a duration of  ~1.26 days, or 4.9 binary orbital periods. During each crossing of the binary orbit with the tertiary body, multiple individual transits are observed as the close binary stars repeatedly move in and out of alignment with the tertiary object. We are at this stage unable to distinguish between a planetary companion to a close eclipsing binary, or a hierarchical triply eclipsing system of three stars. Both possibilities are explored, and the light curves presented.