BEER analysis of Kepler and CoRoT light curves. III. Spectroscopic confirmation of seventy new beaming binaries discovered in CoRoT light curves

(abridged for arXiv) The BEER algorithm searches stellar light curves for the BEaming, Ellipsoidal, and Reflection photometric modulations that are caused by a short-period companion. Applying the search to the first five long-run center CoRoT fields, we identified $481$ non-eclipsing candidates with periodic flux amplitudes of $0.5-87$ mmag. Optimizing the Anglo-Australian-Telescope pointing coordinates and the AAOmega fiber-allocations with dedicated softwares, we acquired six spectra for $231$ candidates and seven spectra for another $50$ candidates in a seven-night campaign. Analysis of the red-arm AAOmega spectra, which covered the range of $8342-8842\AA{}$, yielded a radial-velocity precision of $\sim1$ km/s. Spectra containing lines of more than one star were analyzed with the two-dimensional correlation algorithm TODCOR. The measured radial velocities confirmed the binarity of seventy of the BEER candidates$-45$ single-line binaries, $18$ double-line binaries, and $7$ diluted binaries. We show that red giants introduce a major source of false candidates and demonstrate a way to improve BEER's performance in extracting higher fidelity samples from future searches of CoRoT light curves. The periods of the confirmed binaries span a range of $0.3-10$ days and show a rise in the number of binaries per $\Delta$log$P$ toward longer periods. The estimated mass ratios of the double-line binaries and the mass ratios assigned to the single-line binaries, assuming an isotropic inclination distribution, span a range of $0.03-1$. On the low-mass end, we have detected two brown-dwarf candidates on a $\sim1$ day period orbit. This is the first time non-eclipsing beaming binaries are detected in CoRoT data, and we estimate that $\sim300$ such binaries can be detected in the CoRoT long-run light curves.Comment: 28 pages, 15 figures, and 11 tables. Accepted for publication in A&

Seventy new non-eclipsing BEER binaries discovered in CoRoT lightcurves and confirmed by RVs from AAOmega

We applied the BEER algorithm to the CoRoT lightcurves from the first five LRc fields and identified $481$ non-eclipsing BEER candidates with periodic lightcurve modulations and amplitudes of $0.5-87$ mmag. Medium-resolution spectra of $281$ candidates were obtained in a seven-night AAOmega radial-velocity (RV) campaign, with a precision of $\sim1$ km/s. The RVs confirmed the binarity of $70$ of the BEER candidates, with periods of $0.3-10$ days.Comment: 2 pages, 1 figure, to appear in the CoRoT Symposium 3, Kepler KASC-7 joint meeting, EPJ Web of Conference

Physics of Eclipsing Binaries: Modelling in the new era of ultra-high precision photometry

Recent ultra-high precision observations of eclipsing binaries, especially data acquired by the Kepler satellite, have made accurate light curve modelling increasingly challenging but also more rewarding. In this contribution, we discuss low-amplitude signals in light curves that can now be used to derive physical information about eclipsing binaries but that were unaccessible before the Kepler era. A notable example is the detection of Doppler beaming, which leads to an increase in flux when a star moves towards the satellite and a decrease in flux when it moves away. Similarly, Rømer delays, or light travel time effects, also have to taken into account when modelling the supreme quality data that is now available. The detection of offsets between primary and secondary eclipse phases in binaries with extreme mass ratios, and the observation of Rømer delays in the signals of pulsators in binary stars, have allowed us to determine the orbits of several binaries without the need for spectroscopy. A third example of a small-scale effect that has to be taken into account when modelling specific binary systems, are lensing effects. A new binary light curve modelling code, PHOEBE 2.0, that takes all these effect into account is currently being developed

Kepler KOI-13.01 - Detection of beaming and ellipsoidal modulations pointing to a massive hot Jupiter

KOI-13 was presented by the Kepler team as a candidate for having a giant planet - KOI-13.01, with orbital period of 1.7 d and transit depth of ~0.8%. We have analyzed the Kepler Q2 data of KOI-13, which was publicly available at the time of the submission of this paper, and derived the amplitudes of the beaming, ellipsoidal and reflection modulations: 8.6 +/- 1.1, 66.8 +/- 1.6 and 72.0 +/- 1.5 ppm (parts per million), respectively. After the paper was submitted, Q3 data were released, so we repeated the analysis with the newly available light curve. The results of the two quarters were quite similar. From the amplitude of the beaming modulation we derived a mass of 10 +/- 2 M_Jup for the secondary, suggesting that KOI-13.01 was a massive planet, with one of the largest known radii. We also found in the data a periodicity of unknown origin with a period of 1.0595 d and a peak-to-peak modulation of ~60 ppm. The light curve of Q3 revealed a few more small-amplitude periodicities with similar frequencies. It seemed as if the secondary occultation of KOI-13 was slightly deeper than the reflection peak-to-peak modulation by 16.8 +/- 4.5 ppm. If real, this small difference was a measure of the thermal emission from the night side of KOI-13.01. We estimated the effective temperature to be 2600 +/- 150 K, using a simplistic black-body emissivity approximation. We then derived the planetary geometrical and Bond albedos as a function of the day-side temperature. Our analysis suggested that the Bond albedo of KOI-13.01 might be substantially larger than the geometrical albedo.Comment: 15 pages, 8 figures, accepted for publication in Astronomy and Astrophysic

II.3 Exposure based algorithm for removing systematics out of the CoRoT light curves

This book is dedicated to all the people interested in the CoRoT mission and the beautiful data that were delivered during its six year duration. Either amateurs, professional, young or senior researchers, they will find treasures not only at the time of this publication but also in the future twenty or thirty years. It presents the data in their final version, explains how they have been obtained, how to handle them, describes the tools necessary to understand them, and where to find them. It also highlights the most striking first results obtained up to now. CoRoT has opened several unexpected directions of research and certainly new ones still to be discovered