http://arxiv.org/abs/1505.04570
(abridged for arXiv) The BEER algorithm, introduced by Faigler & Mazeh (2011), searches stellar lightcurves for the BEaming, Ellipsoidal, and Reflection photometric modulations 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 $6-7$ medium-resolution spectra of $281$ 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 TODCOR$-$the two-dimensional correlation algorithm. 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 lightcurves. 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$P$ towards 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 lightcurves.
L. Tal-Or, S. Faigler and T. Mazeh
Tue, 19 May 15
37/78
Comments: 28 pages, 15 figures, and 11 tables. Submitted to A&A
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