J/PASP/123/26ivo://CDS.VizieR/J/PASP/123/26doi:10.26093/cds/vizier.61230026CDSConidis G.J.Sadavoy S.I.Maxwell A.J.Delaney P.A.Manzer L.H.2025-09-09T14:14:06Z2011-03-23T12:06:34ZCDS support team

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

cds-question@unistra.frvariable-starsccd-photometryXX Cyg is a High Amplitude {delta} Scuti star which has been extensively studied because of its changing period. We present 64 new times of maxima which have been combined with 174 times of maxima from literature, in order to give an updated ephemeris and O-C plot for XX Cyg. Its period, currently found to be 0.134865117(3) days, is shown to be increasing continuously, which has lead to a new calculated value of (1/P)(dP/dt)=(1.33+/-0.09)10^-8^yr^-1^2011PASP..123...26Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/PASP/123/26CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/PASP/123/26https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/PASP/123/26http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/PASP/123/26https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/PASP/123/26https://vizier.iucaa.in/viz-bin/votable?-source=J/PASP/123/26http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/PASP/123/26GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/PASP/123/26/table3All O-C values for XX CygrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMaximaTime of Maximum Lightdtime.epochdoubleCycleThe Cycle Number (1)meta.id;meta.mainintO-CObserved minus Calculated Valuedstat.value;stat.fit.omcdoubleSourceReference time of maxima is collected from (include the 19-digit bibcode)meta.ref;time.epochchar