HIDES spectroscopy of bright detached eclipsing binaries from the Kepler field – I. Single-lined objects

• Published in: Monthly notices of the Royal Astronomical Society Vol. 461; no. 3; pp. 2896 - 2913
• Main Authors: Hełminiak, K. G., Ukita, N., Kambe, E., Kozłowski, S. K., Sybilski, P., Ratajczak, M., Maehara, H., Konacki, M.
• Format: Journal Article
• Language: English
• Published: London Oxford University Press 21.09.2016
• Subjects: Astronomy; Detaching; Eclipsing binary stars; Estimates; Hides; Parameters; Space telescopes; Spectral lines; Spectroscopy; Star & galaxy formation; Stars; binaries: eclipsing; stars: evolution; stars: individual: KIC 08718273; stars: individual: KIC 03120320; stars: individual: KIC 10001167; stars: individual: KIC 10991989; stars: individual: KIC 10614012; stars: late-type; stars: individual: KIC 08430105; stars: fundamental parameters; binaries: spectroscopic; stars: individual: KIC 05598639; stars: individual: KIC 10015516; stars: individual: KIC 04758368
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stw1514

We present results of our spectroscopic observations of nine detached eclipsing binaries (DEBs), selected from the Kepler Eclipsing Binary Catalog, that only show one set of spectral lines. Radial velocities (RVs) were calculated from the high-resolution spectra obtained with the HIgh-Dispersion Echelle Spectrograph (HIDES) instrument, attached to the 1.88-m telescope at the Okayama Astrophysical Observatory, and from the public Apache Point Observatory Galactic Evolution Experiment archive. In our sample, we found five single-lined binaries, with one component dominating the spectrum. The orbital and light-curve solutions were found for four of them, and compared with isochrones, in order to estimate absolute physical parameters and evolutionary status of the components. For the fifth case, we only update the orbital parameters, and estimate the properties of the unseen star. Two other systems show orbital motion with a period known from the eclipse timing variations (ETVs). For these we obtained parameters of outer orbits, by translating the ETVs to RVs of the centre of mass of the eclipsing binary, and combining with the RVs of the outer star. Of the two remaining ones, one is most likely a blend of a faint background DEB with a bright foreground star, which lines we see in the spectra, and the last case is possibly a quadruple bearing a sub-stellar mass object. Where possible, we compare our results with literature, especially with results from asteroseismology. We also report possible detections of solar-like oscillations in our RVs.