J/MNRAS/502/6080ivo://CDS.VizieR/J/MNRAS/502/6080doi:10.26093/cds/vizier.75026080CDSOrellana R.B.De Biasi M.S.Paiz L.G.2024-08-21T20:17:19Z2021-03-29T14:27:16ZCDS support team

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

cds-question@unistra.fropen-star-clustersastrometryvisible-astronomytrigonometric-parallaxproper-motionsapparent-magnitudeDue to the high quality of Gaia DR2 stellar parallaxes and proper motions, we can study the Cygnus OB2 region up to G=17.5mag in circular region centred at (l,b)=(79.8{deg},+0.8{deg}) of radius 1{deg}. We detect four over-densities in the Vector Point Diagram. We apply a parametric model of the proper motion distribution and determine their mean proper motions, identify their members and estimate their distances by analyzing the parallaxes of the most probable members. We confirm that one of these regions is Cygnus OB2, whose mean proper motion is (pmRA*cosDE,pmDE)=(-2.71+/-0.02,-4.24+/-0.02)mas/yr. We identify 2767 astrometric members at an estimated distance of 1683 {+/-} 5 pc. A detailed comparison of these members with 333 photometric and spectroscopic Cygnus OB2 members shows that 33 stars of the last group are not members, 16 of them are O-B stars. 300 members in common lead to estimate a distance to the association of 1669+/-6pc. One of the remaining over-densities is the open cluster UCB585 for which we find eight more members, located at ~1460pc. The other two groups count 179 and 188 proper motion members which are distributed throughout the region and situated at a distance of ~1280 pc. The estimated distances of these four groups suggest the existence of different substructures in the Cygnus OB2 region along the line of sight.2021MNRAS.502.6080Ohttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/502/6080CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)J/ApJS/149/123 : WSRT survey of Cygnus OB2 (Setia Gunawan+, 2003)J/ApJ/643/238 : Chandra/2MASS sources in Cygnus OB2 (Butt+, 2006)J/A+A/464/211 : Cyg OB2 Chandra and near-IR obs. (Albacete Colombo+, 2007)J/A+A/472/557 : Cygnus OB2 region 610MHz sources (Marti+, 2007)J/ApJS/184/84 : X-ray sources in Cyg OB2 region (Wright+, 2009)J/A+A/637/A64 : Cygnus OB2 e-MERLIN 21cm survey (COBRaS) (Morford+, 2020)J/MNRAS/460/2593 : Cygnus OB2 DANCe: Proper motion study (Wright+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/502/6080https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/502/6080http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/502/6080https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/502/6080https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/502/6080http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/502/6080GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/502/6080/table2 (New proper motion members of Cygnus OB2)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/502/6080/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/502/6080/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/502/6080/table2?GETtext/xml+votable180.050000true307.7841602366140.969115771520.005555555555555556Cone search capability for table J/MNRAS/502/6080/table6 (Right over-density proper motion members)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/502/6080/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/502/6080/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/502/6080/table6?GETtext/xml+votable180.050000true308.1417057895541.074812457590.005555555555555556Cone search capability for table J/MNRAS/502/6080/table7 (Left over-density proper motion members)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/502/6080/table7?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/502/6080/table7?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/502/6080/table7?GETtext/xml+votable180.050000true307.3106824653940.390963328170.0055555555555555565/3673 6/14667 14670-14671 14689 14691https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/502/6080?format=asciiOpticaldefaultJ/MNRAS/502/6080/table2New proper motion members of Cygnus OB2_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decnullableindexedSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSbarycentric right ascension (ICRS) at Ep=2015.0degpos.eq.ra;meta.mainDE_ICRSbarycentric declination (ICRS) at Ep=2015.0degpos.eq.dec;meta.mainGaiaDR2Gaia DR2 identifiermeta.id;meta.maincharplxAbsolute stellar parallaxmaspos.parallax.trigfloate_plxStandard error of parallaxmasstat.error;pos.parallaxfloatpmRAProper motion in right ascension (pmRA*cosDE)mas/yrpos.pm;pos.eq.rafloate_pmRAStandard error of proper motion in right ascensionmas/yrstat.error;pos.pm;pos.eq.rafloatpmDEProper motion in declinationmas/yrpos.pm;pos.eq.decfloate_pmDEStandard error of proper motion in declinationmas/yrstat.error;pos.pm;pos.eq.decfloatGmagG-band magnitudemagphot.mag;em.optfloatJ/MNRAS/502/6080/table6Right over-density proper motion members_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decnullableindexedSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSbarycentric right ascension (ICRS) at Ep=2015.0degpos.eq.ra;meta.mainDE_ICRSbarycentric declination (ICRS) at Ep=2015.0degpos.eq.dec;meta.mainGaiaDR2Gaia DR2 identifiermeta.id;meta.maincharplxAbsolute stellar parallaxmaspos.parallax.trigfloate_plxStandard error of parallaxmasstat.error;pos.parallaxfloatpmRAProper motion in right ascension (pmRA*cosDE)mas/yrpos.pm;pos.eq.rafloate_pmRAStandard error of proper motion in right ascensionmas/yrstat.error;pos.pm;pos.eq.rafloatpmDEProper motion in declinationmas/yrpos.pm;pos.eq.decfloate_pmDEStandard error of proper motion in declinationmas/yrstat.error;pos.pm;pos.eq.decfloatGmagG-band magnitudemagphot.mag;em.optfloatJ/MNRAS/502/6080/table7Left over-density proper motion memberse_pmRAStandard error of proper motion in right ascensionmas/yrstat.error;pos.pm;pos.eq.rafloatpmDEProper motion in declinationmas/yrpos.pm;pos.eq.decfloate_pmDEStandard error of proper motion in declinationmas/yrstat.error;pos.pm;pos.eq.decfloatGmagG-band magnitudemagphot.mag;em.optfloat_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decnullableindexedSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSbarycentric right ascension (ICRS) at Ep=2015.0degpos.eq.ra;meta.mainDE_ICRSbarycentric declination (ICRS) at Ep=2015.0degpos.eq.dec;meta.mainGaiaDR2Gaia DR2 identifiermeta.id;meta.maincharplxAbsolute stellar parallaxmaspos.parallax.trigfloate_plxStandard error of parallaxmasstat.error;pos.parallaxfloatpmRAProper motion in right ascension (pmRA*cosDE)mas/yrpos.pm;pos.eq.rafloat