J/AJ/149/93ivo://CDS.VizieR/J/AJ/149/93doi:10.26093/cds/vizier.51490093CDSLee J.W.Hong K.Hinse T.C.2017-06-19T07:57:52Z2015-04-01T16:04:29ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.freclipsing-binary-starsWe present the physical properties of KIC 5621294, showing light and timing variations from the Kepler photometry. Its light curve displays partial eclipses and the O'Connell effect, with Max II fainter than Max I, which was fitted quite well by applying third-body and spot effects to the system. The results indicate that the eclipsing pair is a classical Algol-type system with parameters of q=0.22, i=76.8{deg}, and {Delta}(T_1_-T_2_)=4235K, in which the detached primary component fills about 77% of its limiting lobe. Striking discrepancies exist between the primary and secondary eclipse times obtained with the method of Kwee & van Woerden. These are mainly caused by surface inhomogeneities due to spot activity detected in our light curve synthesis. The 1253 light curve timings from the Wilson-Devinney code were used for a period study. It was found that the orbital period of KIC 5621294 has varied due to periodic variation overlaid on a downward parabola. The sinusoidal variation with a period of 961days and a semi-amplitude of 22.5s most likely arises from a light-time effect due to a third component with a mass of M_3_sini_3_=46.9M_Jup_, which is in good agreement with that calculated from the light curve itself. If its orbital inclination is larger than about 40{deg}, the mass of the circumbinary object would possibly match a brown dwarf. The parabolic variation could not be fully explained by either a mass transfer between the binary components or angular momentum via magnetic braking. It is possible that the parabola may be the only observed part of a period modulation caused by the presence of another companion in a wider orbit.2015AJ....149...93Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/149/93CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)V/118 : Catalog of eclipsing binaries parameters (Perevozkina+, 1999)J/AJ/148/37 : Long-term photometric behavior of V404 Lyr (Lee+, 2014)J/AJ/147/91 : Differential BVR light curves of V407 Peg (Lee+, 2014)J/AJ/147/45 : Kepler mission. IV. Timings for close binaries (Conroy+, 2014)J/AJ/143/137 : Minima of eclipsing binaries from a Kepler survey (Gies+, 2012)J/AJ/142/112 : KIC photometric calibration (Brown+, 2011)J/AJ/139/2669 : CL Aur BVRI light curves (Lee+, 2010)J/AJ/137/3181 : HW Vir differential VR light curves (Lee+, 2009)J/A+A/450/681 : Companions to close spectroscopic binaries (Tokovinin+, 2006)http://www.as.up.krakow.pl/o-c/ : Atlas of O-C diagrams of eclipsing binarieshttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/149/93https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/149/93http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/149/93https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/149/93https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/149/93http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/149/93GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/149/93/table2Minimum timings determined by the method of Kwee & van Woerden (1956BAN....12..327K)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDBarycentric Julian Datedtime.epochdoublee_BJDUncertainty in BJDdstat.errordoubleEpoch[-765/799.5] Cycle number (.5 for type-II)meta.number;time.periodfloatO-CObserved minus Calculated timing (1)dtime.epoch;stat.fit.omcdoubleMinMinimum type (I or II)meta.notenullableJ/AJ/149/93/table3Minimum timings determined by the Wilson-Devinney code (Wilson & Devinney, 1971ApJ...166..605W; Van Hamme & Wilson, 2007ApJ...661.1129V)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDBarycentric Julian Datedtime.epochdoublee_BJDUncertainty in BJDdstat.errordoubleEpoch[-766/799] Cycle numbermeta.number;time.periodintO-CObserved minus Calculated timing (from the complete ephemeris) (1)dtime.epoch;stat.fit.omcdouble