J/ApJ/622/1052ivo://CDS.VizieR/J/ApJ/622/1052doi:10.26093/cds/vizier.16221052CDSMcSwain M.V.Gies D.R.2017-10-09T13:34:19Z2006-01-28T11:53:11ZCDS support team

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

cds-question@unistra.fropen-star-clustersbe-starsvisible-astronomymedium-band-photometryh-alpha-photometryWe describe a technique to identify Be stars in open clusters using Stroemgren b, y, and narrowband H{alpha} photometry. We first identify the B-type stars of the cluster using a theoretical isochrone fit to the (b-y, y) color-magnitude diagram. The strongest Be stars are easily identified in a (b-y, y-H{alpha}) color-color diagram, but those with weaker H{alpha} emission (classified as possible Be star detections) may be confused with evolved or foreground stars. Here we present such photometry plus H{alpha} spectroscopy of members of the cluster NGC 3766 to demonstrate the accuracy of our technique.2005ApJ...622.1052Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/622/1052CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/119/271 : Be stars uvby{beta} photometry (Fabregat+, 1996)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/622/1052https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/622/1052http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/622/1052https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/622/1052https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/622/1052http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/622/1052GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/622/1052/table1 (Photometry of NGC 3766)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/622/1052/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/622/1052/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/622/1052/table1?GETtext/xml+votable180.050000true173.9969167-61.48730560.0055555555555555566/37901 37912https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/622/1052?format=asciiOpticaldefaultJ/ApJ/622/1052/table1Photometry of NGC 3766CodeStellar type (1)charrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqStar identification number in NGC 3766intRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainymagStromgren y band magnitudemagfloate_ymagError in ymagmagfloatb-yStromgren (b-y) color indexmagfloate_b-yError in b-ymagfloaty-HaThe (y-H{alpha}) color indexmagfloate_y-HaError in y-HamagfloatWEBDA? The WEBDA database number (2)intnullableONamesOther identifierscharSimbadSimbad column added by the CDSchar