J/A+A/486/453ivo://CDS.VizieR/J/A+A/486/453doi:10.26093/cds/vizier.34860453CDSComeron F.Pasquali A.Figueras F.Torra J.2008-12-17T12:07:03Z2008-12-17T13:02:33ZCDS support team

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

cds-question@unistra.fropen-star-clustersearly-type-starsinfrared-photometryCygnus OB2 is one of the richest OB associations in the local Galaxy, and is located in a vast complex containing several other associations, clusters, molecular clouds, and HII regions. However, the stellar content of Cygnus OB2 and its surroundings remains rather poorly known largely due to the considerable reddening in its direction at visible wavelength. We investigate the possible existence of an extended halo of early-type stars around Cygnus OB2, which is hinted at by near-infrared color-color diagrams, and its relationship to Cygnus OB2 itself, as well as to the nearby association Cygnus OB9 and to the star forming regions in the Cygnus X North complex. Candidate selection is made with photometry in the 2MASS all-sky point source catalog. The early-type nature of the selected candidates is confirmed or discarded through our infrared spectroscopy at low resolution. In addition, spectral classifications in the visible are presented for many lightly-reddened stars.2008A&A...486..453Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/486/453CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/101/1408 : Massive stars in Cyg OB2. (Massey+ 1991)J/AJ/107/1433 : Cygnus OB2 polarimetry (Kobulnicky+, 1994)J/A+AS/111/407 : VI Cygni red + reddened stars (Parthasarathy+, 1995)J/MNRAS/298/753 : Variables in Cygnus OB2 (Pigulski+ 1998)J/ApJS/149/123 : WSRT survey of Cygnus OB2 (Setia Gunawan+, 2003)J/A+A/464/211 : Chandra and near-IR obs. of Cyg OB2 (Albacete Colombo+, 2007)J/A+A/472/557 : Cygnus OB2 region 610MHz sources (Marti+, 2007)J/A+A/474/495 : X-ray flares from CygOB2 young stars (Albacete Colombo+ 2007)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/486/453https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/486/453http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/486/453https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/486/453https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/486/453http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/486/453GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/486/453/tables (JKHs photometry of early-type stars (tables 1-9))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/486/453/tables?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/486/453/tables?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/486/453/tables?GETtext/xml+votable180.050000true307.92562542.43144440.0055555555555555565/3667 3672 6/14666-14667 14680 14682 14693-14697 14700-14701 14704 14706https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/486/453?format=asciiInfrareddefaultJ/A+A/486/453/tablesJKHs photometry of early-type stars (tables 1-9)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTab[1/9] Original table number (1)meta.id;meta.mainintTypeType of star (2)src.classchar[CPF2008]Star sequential numbermeta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainJmag? J magnitudemagphot.mag;em.IR.JfloatnullableHmag? H magnitudemagphot.mag;em.IR.HfloatnullableKsmagKs magnitudemagphot.mag;em.IR.KfloatSpTypeVisual MK spectral classificationsrc.spTypecharNotesNotes, in notes.dat filemeta.notecharONameOther namemeta.idcharJ/A+A/486/453/notesIndividual notesTextText of the notemeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNoteNote numbermeta.noteint