BEER analysis of Kepler and CoRoT light curves: discovering binaries and exoplanets

Abstract

This thesis consists of seven scientific papers that cover the proof-of-concept, the development, and discoveries made through the use of the BEER (BEaming, Ellipsoidal, and Reflection) algorithm for searching for companions in the light curves from the Kepler and CoRoT space telescopes. Paper I presents the detection of the ellipsoidal and the beaming effects in the CoRoT light curve of CoRoT-3, a system of a $22$$M_{\rm Jup}$ brown dwarf orbiting an F star with an orbital period of $4.3$ days. This work served as a proof-of-concept that these effects are detectable in the space light curves of systems with brown-dwarf or planetary secondaries, thus indicating that similar modulations may be detected in the light curves of non-transiting systems. Abridged... The last study, Paper VII, demonstrates the different strengths and utility of the BEER search algorithm. It presents the discovery of four short-period eclipsing binaries in the Kepler light curves, consisting of an A-star primary and a low-mass WD secondary (dA+WD). The systems show BEER phase modulations together with primary and secondary eclipses. These add to the 6 Kepler, and 18 WASP, previously known short-period eclipsing dA+WD binaries. The paper shows that three of the new systems harbor the smallest WDs detected so far in such binaries. These three binaries extend the previously known population to older systems with cooler and smaller WD secondaries, allowing to test binary evolution theories in a parameter region not observed before. The seven papers illustrate the effectiveness of the BEER algorithm in finding both common stellar binaries and rare astrophysical objects. As such, the BEER tool can serve as an important component in the virtual astronomy toolbox for mining the vast astronomical data produced by current and future photometric surveys. Abridged.