J/AJ/146/79ivo://CDS.VizieR/J/AJ/146/79doi:10.26093/cds/vizier.51460079CDSLiao W.-P.Qian S.-B.Li K.He J.-J.Zhao E.-G.Zhou X.2017-07-11T13:08:23Z2014-07-10T09:23:28ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsinfrared-photometryvisible-astronomybroad-band-photometryNew multi-color CCD photometric light curves of the eclipsing binary EP And were obtained over six nights in 2006, 2011, and 2012. Using the Wilson-Devinney code, we computed the photometric elements of this system. It was discovered that EP And is a W-type W UMa contact binary system with a mass ratio of q=2.685 and a degree of contact factor f=24.9%, rather than an A-type system. Combining 28 newly determined times of minimum light derived from 1999 to 2012 with others collected from the literature, a long-term increase (dP/dt=+5.22x10^-8^days/yr) with a sinusoidal variation (A=0.0109days; T=40.89yr) in the orbital period was found. The orbital period secular increases may be interpreted as conservative mass transfer from the less massive component to the more massive one, and cyclic variations of the orbital period may be caused by the light-travel time effect through the presence of a third body. The evolutionary status and the age of the system are also discussed.2013AJ....146...79Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/146/79CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)V/119 : Catalogue of field contact binary stars (Pribulla+, 2003)J/AJ/145/100 : Differential BVR light curves of EP And (Lee+, 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/146/79https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/146/79http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/146/79https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/146/79https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/146/79http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/146/79GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/AJ/146/79/obsCombined table from original tablesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFlt[BVRI] Filter used in the observation (BVRI)instr.setup;obscharHJDHeliocentric Julian Date of the observationdtime.epochdoubledmagDifferential magnitude in Fltmagphot.mag;arith.difffloat