J/AJ/149/120ivo://CDS.VizieR/J/AJ/149/120doi:10.26093/cds/vizier.51490120CDSLi K.Hu S.-M.Guo D.-F.Jiang Y.-G.Gao Y.-G.Chen X.Odell A.P.2017-06-22T14:29:11Z2015-04-24T15:58:11ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsradial-velocityTY UMa is an F-type eclipsing binary star. Four-color light curves and radial velocities of this system were presented and simultaneously analyzed using the W-D code. It is found that TY UMa is a W-subtype shallow contact binary system (f=13.4%) with a mass ratio of q=2.523. In order to explain the asymmetric light curve of this binary, a dark spot on the less massive component was employed. Our newly determined 31 times of minimum light, including those collected from the literature, have been used to analyze orbital period changes of TY UMa. The complicated period variation could be sorted into a secular period increase at a rate of d_p_/d_t_=+5.18(+/-0.21)x10^-7^days/yr, a 51.7yr periodic modulation (A_3_=0.0182days), and a very small amplitude cyclic oscillation with a period of 10.0yr (A_4_=0.0015days). The long-term increase of the period can be explained by mass transfer from the less massive component to the more massive one. The Applegate mechanism may impossibly explain the two cyclic components in the period. The two cyclic variations are very likely caused by the light travel time effect of third and fourth components, suggesting that TY UMa is a quadruple system.2015AJ....149..120Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/149/120CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)J/AJ/147/98 : Times of minimum light for EQ Tau (Li+, 2014)J/AJ/143/99 : Photometry of W UMa eclipsing binaries (Terrell+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/149/120https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/149/120http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/149/120https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/149/120https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/149/120http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/149/120GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/149/120/table1Heliocentric radial velocities of TY UMarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Date (HJD-2450000)dtime.epochdoublePhase[0/1] Phase (1)time.phasefloatHRV1[-100/109] Primary heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_HRV1Uncertainty in HRV1km/sstat.errorfloatHRV2[-276/247] Secondary heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloate_HRV2Uncertainty in HRV2km/sstat.errorfloatJ/AJ/149/120/table3Observed times of minimum light for TY UMaO-C1Primary O-C residual (2)dstat.fit.residualfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Date of minimum light (HJD-2400000)dtime.epochdoubleMethDetection method (ccd, phg, pe, or vis) (1)meta.code;obscharType[ps] Type of minimum light (p=primary, s=secondary)meta.notecharE[-37907/48701] Epoch (cycle) (2)time.epochdoubleO-C2Secondary O-C residual (3)dstat.fit.residualfloatO-C3Tertiary O-C residual (4)dstat.fit.residualfloatRes? Quadruple O-C residual (5)dstat.fit.residualfloatnullableRef[1/85] Reference; in refs.dat filemeta.ref;pos.frameintJ/AJ/149/120/refsReferencesComCommentsmeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReference identifierpos.frame;meta.mainintprimaryBibCodeBibliographic Codemeta.bib.bibcodecharAutAuthor's namemeta.bib.authorchar