A comprehensive study of theKeplertriples via eclipse timing

Abstract

We produce and analyze eclipse time variation (ETV) curves for some 2600 targeted main-field Kepler binaries. We find good to excellent evidence for a third body in 222 systems via either the light-travel-time (LTTE) or dynamical effect delays. Approximately half of these systems have been discussed in previous work, while the rest are newly reported here. Via detailed analysis of the ETV curves using high-level analytic approximations, we are able to extract system masses and information about the three-dimensional characteristics of the triple for 62 systems which exhibit both LTTE and dynamical delays. For the remaining 160 systems whose ETV curves are dominated by LTTE delays we are able to extract the outer orbital period, eccentricity, and longitude of periastron as well as the mass function of the triple. In general, our solutions improve upon those published earlier. New techniques of preprocessing the flux time series are applied to eliminate false positive triples and to enhance the ETV curves. The set of triples with outer orbital periods shorter than ∼2000 days is now sufficiently numerous for meaningful statistical analysis. We find that (i) as predicted, there is a peak near i m 40• in the distribution of the triple vs. inner binary mutual inclination angles that provides strong confirmation of the operation of Kozai-Lidov cycles with tidal friction; (ii) the median eccentricity of the third-body orbits is e 2 = 0.35; (iii) there is a deficit of triple systems with binary periods 1 day and outer periods between ∼50 and 200 days which might help guide the refinement of theories of the formation and evolution of close binaries; and (iv) the substantial fraction of Kepler binaries which have third-body companions is consistent with a very large fraction of all binaries being part of triples.

HIDES spectroscopy of bright detached eclipsing binaries from the Kepler field – II. Double- and triple-lined objects

“…In much better agreement with ours are the param- eters given by Borkovits et al (2016). They, however, assume the mutual inclination to be zero, and argue that a small non-zero value (i m < 10 • ) would produce significant eclipse depth variations, and that their solution rules out large values of i m .…”

“…They, however, assume the mutual inclination to be zero, and argue that a small non-zero value (i m < 10 • ) would produce significant eclipse depth variations, and that their solution rules out large values of i m . Table 4 shows a comparison of our results with those obtained by Rappaport et al (2013) and Borkovits et al (2016).…”

“…It probably hosts a non-transiting, bin/TblView/nph-tblView?app=ExoTbls&config=koi circumbinary planet, which was first announced in a conference presentation by W. Welsh 3 but the proper publication is still to be announced (Fabrycky et al, in prep.). Borkovits et al (2016) confirmed such possibility, by finding periodic modulations of the ETVs. Till now, absolute stellar parameters have also been presented on a conference only, first by Sharp et al (2014).…”

“…KIC 06525196 = KOI 5293, TYC 3143-604-1: It is a target with periodic eclipse timing variations (ETV; P et v = 415.8 d), identified first by Rappaport et al (2013), and later by Borkovits et al (2016). Both groups give the orbital parameters of the outer orbit.…”

“…The parameters of the outer orbit were previously estimated from ETVs (Rappaport et al 2013;Borkovits et al 2016), and the period is short enough to be covered with observations during only few semesters. We assumed that the outer orbit is Keplerian, as the distance to the third star B is much larger than the separation between Aa and Ab.…”