Searching For Transiting Circumbinary Planets in CoRoT and Ground-Based Data Using CB-BLS

TL;DR

This paper advances the CB-BLS algorithm for detecting transiting circumbinary planets, demonstrating its improved sensitivity and application to real data, which enhances the search for such planets in wide-field surveys.

Contribution

It introduces improvements to CB-BLS, including detection limits analysis and detrending methods, enabling reliable application to real observational data.

Findings

CB-BLS successfully detects simulated planets in real CoRoT data.

The method correctly detrends bright eclipsing binaries from observations.

Application to real data shows promise for future wide-field survey searches.

Abstract

Aims. We search for transiting circumbinary (CB) planets around eclipsing binaries (EBs). Methods. CB-BLS is a recently-introduced algorithm for the detection of transiting CB planets around EBs.We describe progress in search sensitivity, generality and capability of CB-BLS, and detection tests of CB-BLS on simulated data. We also describe an analytical approach for the determination of CB-BLS detection limits, and a method for the correct detrending of intrinsically-variable stars. Results. We present some blind-tests with simulated planets injected to real CoRoT data. The presented upgrades to CB-BLS allowed it to detect all the blind tests successfully, and these detections were in line with the detection limits analysis. We also correctly detrend bright eclipsing binaries from observations by the TrES planet search, and present some of the first results of applying CB-BLS to multiple real light curves from a wide-field survey. Conclusions. CB-BLS is now mature enough for its application to real data, and the presented processing scheme will serve as the template for our future applications of CB-BLS to data from wide-field surveys such as CoRoT. Being able to put constraints even on non-detection will help to determine the correct frequency of CB planets, contributing to the understanding of planet formation in general. Still, searching for transiting CB planets is still a learning experience, similarly to the state of transiting planets around single stars only a few years ago. The recent rapid progress in this front, coupled with the exquisite quality of space-based photometry, allows to realistically expect that if transiting CB planets exist - then they will soon be found.