J/AJ/148/96ivo://CDS.VizieR/J/AJ/148/96doi:10.26093/cds/vizier.51480096CDSLi K.Hu S.-M.Guo D.-F.Jiang Y.-G.Gao D.-Y.Chen X.2020-08-07T07:17:21Z2014-12-09T15:32:12ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsThe first photometric analysis of IR Cas was carried out based on the new observed BVRI light curves. The symmetric light curves and nearly flat secondary minimum indicate that very precise photometric results can be determined. We found that IR Cas is a near contact binary with the primary component filling its Roche lobe. An analysis of the O-C diagram based on all available times of minimum light reveals evidence for a periodic change with a semi-amplitude of 0.0153days and a period of 39.7yr superimposed on a secular decrease at a rate of dp/dt=-1.28(+/-0.09)x10^-7^days/yr. The most reasonable explanation for the periodic change is the light time-travel effect due to a third body. The period decrease may be caused by mass transfer from the primary component to the secondary. With the decreasing period, IR Cas would eventually evolve into a contact system.2014AJ....148...96Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/148/96CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)J/AJ/144/37 : BVRI photometry of the eclipsing binary BS Vul (Zhu+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/148/96https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/148/96http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/148/96https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/148/96https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/148/96http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/148/96GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/AJ/148/96/table2Times of minimum light for IR CasrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Datedtime.epochdoublef_HJD[1] This minimum is discarded during the fittingmeta.codecharMethObservational method used (1)instr.setupcharTypeEclipse type (p=primary, s=secondary)meta.notecharEpochEpoch numbermeta.id;meta.maindoubleO-C1The (O-C)_1_ residual (2)dstat.fit.residualfloatO-C2The (O-C)_2_ residual from the quadratic term (equation (2) in the paper)dstat.fit.residualfloatResResidualdstat.fit.residualfloatJournalJournal name (4)meta.bib.journalcharVol? Volume numbermeta.bib.volumeintnullablePage? Page numbermeta.bib.pageintnullableBibCodeBibliographic codemeta.bib.bibcodecharCatVizieR catalogmeta.id;meta.tablechar