J/A+AS/145/365ivo://CDS.VizieR/J/A+AS/145/365CDSGupta A.C.Subramaniam A.Sagar R.Griffiths W.K.2000-12-10T14:34:16Z2000-12-10T15:33:49ZCDS support team

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

cds-question@unistra.fropen-star-clustersccd-photometryvisible-astronomykron-cousins-photometryCCD photometry of the northern open star cluster NGC 7790 has been carried out in BVI photometric passbands down to V~21mag for 1150 stars of which for ~700 stars, the data is obtained for the first time. We derive the most reliable parameters for this cluster using all the available photometric, spectroscopic and proper motion data. The interstellar extinction over the cluster area is uniform and normal with E(B-V)=0.51+/-0.03mag. We determine a distance of 3.3+/-0.23Kpc to the cluster. The theoretical isochrone fittings to the Cepheid variables as well as the evolved part of the main-sequence near turn-off point indicate that the cluster is 120+/-20Myr old. We estimate the cluster radius to be 3.7' using radial stellar density profile. Both the distance and age determined using period luminosity/age relations for the Cepheid variables are consistent with their membership of the cluster. This unique opportunity has therefore been used to refine the zero-point of the period-luminosity relation for the Galactic Cepheids.2000A&AS..145..365Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+AS/145/365CatalogResearchIsServedByTAP VizieR generic servicerelated-toV/28 : Proper motions and UBV phot. in 4 open clusters (Frolov 1980)J/PASP/104/553 : CCD Standard Fields (Odewahn+ 1992)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+AS/145/365https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+AS/145/365http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+AS/145/365https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+AS/145/365https://vizier.iucaa.in/viz-bin/votable?-source=J/A+AS/145/365http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+AS/145/365GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/A+AS/145/365/table1Relative (X, Y) pixel positions and CCD BVI magnitudes of stars measured in the field of NGC 7790 are presented.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number (1)meta.idintXposX position (2)pixpos.cartesian.x;instr.detfloatYposY position (2)pixpos.cartesian.y;instr.detfloatVmagV magnitudemagphot.mag;em.opt.VfloatB-V? B-V colour indexmagphot.color;em.opt.B;em.opt.VfloatnullableV-IV-I Cousins colour indexmagphot.color;em.opt.V;em.opt.IfloatNamesOther identifications, separated by commas (3)meta.idcharOdewahnDisplay the parameters from Odewahn (J/PASP/104/553)meta.refchar