J/MNRAS/490/440ivo://CDS.VizieR/J/MNRAS/490/440doi:10.26093/cds/vizier.74900440CDSLim B.Naze Y.Gosset E.Rauw G.2024-08-20T20:14:06Z2023-02-17T13:00:10ZCDS support team

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

cds-question@unistra.frob-starsstellar-associationsstellar-spectral-typesvisible-astronomytrigonometric-parallaxproper-motionsastrometryOB associations are the prime star-forming sites in galaxies. However, the detailed formation process of such stellar systems still remains a mystery. In this context, identifying the presence of substructures may help in tracing the footprints of their formation process. Here, we present a kinematic study of the two massive OB associations Cygnus OB2 and Carina OB1 using the precise astrometry from the Gaia Data Release 2 and radial velocities. From the parallaxes of stars, these OB associations are confirmed to be genuine stellar systems. Both Cygnus OB2 and Carina OB1 are composed of a few dense clusters and a halo which have different kinematic properties: the clusters occupy regions of 5-8 parsecs in diameter and display small dispersions in proper motion, while the haloes spread over tens of parsecs with two to three times larger dispersions in proper motion. This is reminiscent of the so-called line width-size relation of molecular clouds related to turbulence. Considering that the kinematics and structural features were inherited from those of their natal clouds would then imply that the formation of OB associations may result from structure formation driven by supersonic turbulence, rather than from the dynamical evolution of individual embedded clusters.2019MNRAS.490..440Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/490/440CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)J/MNRAS/449/741 : The massive star population of Cygnus OB2 (Wright+, 2015)J/ApJS/194/7 : X-ray properties of O and B stars in Carina (Naze+, 2011)B/mk : Catalogue of Stellar Spectral ClassificationsJ/AJ/143/41 : UBVIc CCD photometry of star clusters Tr14 and Tr16III/274 : Galactic O-Star Spectroscopic Survey (GOSSS) (Sota+, 2014)J/A+A/603/A81 : Trumpler 14 and 16 in the Carina nebula (Damiani+, 2017)J/AJ/155/190 : Carina Nebula hot stars: stellar parameters and RVshttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/490/440https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/490/440http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/490/440https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/490/440https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/490/440http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/490/440GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/490/440/table1 (Catalogue of high-mass stars in Cygnus OB2)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/490/440/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/490/440/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/490/440/table1?GETtext/xml+votable180.050000true308.012916741.25552780.005555555555555556Cone search capability for table J/MNRAS/490/440/table2 (Catalogue of high-mass stars in Carina OB1)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/490/440/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/490/440/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/490/440/table2?GETtext/xml+votable180.050000true160.0515833-59.80269440.0055555555555555566/14670 14692-14694 37247 37333 37335 37930 38016-380181.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/490/440?format=asciiOpticaldefaultJ/MNRAS/490/440/table1Catalogue of high-mass stars in Cygnus OB2SimbadNameSimbad column added by the CDSmeta.idcharnullablee_BPmag? Error on BPmagmagstat.error;phot.magfloatnullableRPmag? Gaia DR2 RP-band magnitudemagphot.mag;em.opt.Rfloatnullablee_RPmag? Error on RPmagmagstat.error;phot.magfloatnullableBP-RP? Gaia DR2 BP-RP colourmagphot.color;em.opt.B;em.opt.RdoublenullableW15Displat the data of Wright et al., 2015, Cat. J/MNRAS/449/741meta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/167] Internal object identifiermeta.id;meta.mainintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainSpTypeSpectral type from Wright et al. (2015MNRAS.449..741W, Cat. J/MNRAS/449/741)src.spTypecharplx? Parallax from Gaia DR2maspos.parallax.trigfloatnullablee_plx? Error on plxmasstat.error;pos.parallaxfloatnullablepmRA? Proper motion in right ascension from Gaia DR2mas/yrpos.pm;pos.eq.rafloatnullablee_pmRA? Error on pmRAmas/yrstat.error;pos.pm;pos.eq.rafloatnullablepmDE? Proper motion in declination from Gaia DR2mas/yrpos.pm;pos.eq.decfloatnullablee_pmDE? Error on pmDEmas/yrstat.error;pos.pm;pos.eq.decfloatnullableDup[0/1]? Duplication flag from Gaia DR2meta.codeintnullableGmag? Gaia DR2 G-band magnitudemagphot.mag;em.optfloatnullablee_Gmag? Error on Gmagmagstat.error;phot.magfloatnullableBPmag? Gaia DR2 BP-band magnitudemagphot.mag;em.opt.BfloatnullableJ/MNRAS/490/440/table2Catalogue of high-mass stars in Carina OB1SimbadNameSimbad column added by the CDSmeta.idcharnullablee_pmRA? Error on pmRAmas/yrstat.error;pos.pm;pos.eq.rafloatnullablepmDE? Proper motion in declination from Gaia DR2mas/yrpos.pm;pos.eq.decfloatnullablee_pmDE? Error on pmDEmas/yrstat.error;pos.pm;pos.eq.decfloatnullableDup[0/1]? Duplication flag from Gaia DR2meta.codeintnullableGmag? Gaia DR2 G-band magnitudemagphot.mag;em.optfloatnullablee_Gmag? Error on Gmagmagstat.error;phot.magfloatnullableBPmag? Gaia DR2 BP-band magnitudemagphot.mag;em.opt.Bfloatnullablee_BPmag? Error on BPmagmagstat.error;phot.magfloatnullableRPmag? Gaia DR2 RP-band magnitudemagphot.mag;em.opt.Rfloatnullablee_RPmag? Error on RPmagmagstat.error;phot.magfloatnullableBP-RP? Gaia DR2 BP-RP colourmagphot.color;em.opt.B;em.opt.RfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[1/306] Internal object identifiermeta.id;meta.mainintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainSpTypeSpectral typesrc.spTypecharr_SpTypeReference for SpType (1)meta.ref;pos.framecharplx? Parallax from Gaia DR2maspos.parallax.trigfloatnullablee_plx? Error on plxmasstat.error;pos.parallaxfloatnullablepmRA? Proper motion in right ascension from Gaia DR2mas/yrpos.pm;pos.eq.rafloatnullable