J/A+A/621/A115ivo://CDS.VizieR/J/A+A/621/A115doi:10.26093/cds/vizier.36210115CDSCantat-Gaudin T.Mapelli M.Balaguer-Nunez L.Jordi C.Sacco G.,Vallenari A.2020-11-04T15:46:28Z2019-01-17T09:08:08ZCDS support team

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

cds-question@unistra.frstellar-associationsstellar-populationsThe Vela OB2 association is a group of 10Myr stars exhibiting a complex spatial and kinematic substructure. The all-sky Gaia DR2 catalogue contains proper motions, parallaxes (a proxy for distance) and photometry that allow us to separate the various components of Vela OB2. We characterise the distribution of the Vela OB2 stars on a large spatial scale, and study its internal kinematics and dynamic history. We make use of Gaia DR2 astrometry and published Gaia-ESO Survey data. We apply an unsupervised classification algorithm to determine groups of stars with common proper motions and parallaxes. We find that the association is made up of a number of small groups, with a total current mass over 2330M_{sun}_. The three-dimensional distribution of these young stars trace the edge of the gas and dust structure known as the IRAS Vela Shell across 180 pc and shows clear signs of expansion. We propose a common history for Vela OB2 and the IRAS Vela Shell. The event that caused the expansion of the shell happened before the Vela OB2 stars formed, imprinted the expansion in the gas the stars formed from, and most likely triggered star formation.2019A&A...621A.115Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/621/A115CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/621/A115https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/621/A115http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/621/A115https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/621/A115https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/621/A115http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/621/A115GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/621/A115/velaypop (List of probable members and membership probabilities)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/621/A115/velaypop?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/621/A115/velaypop?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/621/A115/velaypop?GETtext/xml+votable180.050000true122.822457166346-46.220947485654890.0055555555555555564/2449-2451 2454 2456 5/9466 9783 9789 9791 9793-9795 9810 9828-9830 9832 9835 9841-9844 9848-9849 9851-9852 9854 9931 6/37621 37626-37627 37629 37771 37777 37789 37793-37795 37798 37801-37803 37806-37807 37814 37816-37818 37821-37824 37833 37844 37870 37881 38555 38569 38981 38989 38996 38998-38999 39007 39028 39031 39034 39037 39039 39122 39125 39127 39131 39145 39155 39161 39163 39169-39171 39232 39234-39235 39238 39245-39247 39252 39258 39282-39284 39288 39290-39294 39324-39326 39332-39334 39336 39338 39344-39345 39347 39349-39350 39352 39354 39357 39359-39361 39363 39380 39382-39386 39388-39390 39412 39414 39420 39422 39494 39506-39509 39511-39512 39515 39517 39633 39638 39641 39682-39685 39692 39701 39704 39711 39738 39741-39742 39745 39750 39752-39753 39760-39761 39763-39764 39766-39769 39771 39773 39777 39779 39782 39785 39788 39812 39826 39841 39847 39978 40064 40066https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/621/A115?format=asciidefaultJ/A+A/621/A115/velaypopList of probable members and membership probabilitiesSourceUnique source identifier (source_id)meta.id;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSBarycentric right ascension (ICRS) at Ep=2015.5 (ra)degpos.eq.ra;meta.mainDE_ICRSBarycentric declination (ICRS) at Ep=2015.5 (dec)degpos.eq.dec;meta.mainGLONGalactic longitude (l)degpos.galactic.lonGLATGalactic latitude (b)degpos.galactic.latdoublePlxAbsolute stellar parallax (parallax)maspos.parallaxdoublee_PlxStandard error of parallax (parallax_error)masstat.error;pos.parallaxdoublepmRAProper motion in right ascension direction (pmRA*cosDE) (pmra)mas/yrpos.pm;pos.eq.radoublee_pmRAStandard error of proper motion in right ascension direction (pmra_error)mas/yrstat.error;pos.pm;pos.eq.radoublepmDEProper motion in declination direction (pmdec)mas/yrpos.pm;pos.eq.decdoublee_pmDEStandard error of proper motion in declination direction (pmdec_error)mas/yrstat.error;pos.pm;pos.eq.decdoubleRADEcorCorrelation between right ascension and declination (ra_dec_corr)stat.correlationRAPlxcorCorrelation between right ascension and parallax (ra_parallax_corr)stat.correlationRApmRAcorCorrelation between right ascension and proper motion in right ascension (ra_pmra_corr)stat.correlationRApmDEcorCorrelation between right ascension and proper motion in declination (ra_pmdec_corr)stat.correlationDEPlxcorCorrelation between declination and parallax (dec_parallax_corr)stat.correlationDEpmRAcorCorrelation between declination and proper motion in right ascension (dec_pmra_corr)stat.correlationDEpmDEcorCorrelation between declination and proper motion in declination (dec_pmdec_corr)stat.correlationPlxpmRAcorCorrelation between parallax and proper motion in right ascension (parallax_pmra_corr)stat.correlationdoublePlxpmDEcorCorrelation between parallax and proper motion in declination (parallax_pmdec_corr)stat.correlationdoublepmRApmDEcorCorrelation between proper motion in right ascension and proper motion in declination (pmra_pmdec_corr)stat.correlationdoubleo_GmagNumber of observations contributing to G photometry (phot_g_n_obs)meta.numberintGmagG-band mean magnitude (Vega) (phot_g_mean_mag)magphot.mag;em.optdoubleBPmagIntegrated BP mean magnitude (Vega) (phot_bp_mean_mag)magphot.flux.density;em.opt.BdoubleRPmagIntegrated RP mean magnitude (Vega) (phot_rp_mean_mag)magphot.flux.density;em.opt.RdoubleBP-RPBP-RP colour (bp_rp)magphot.color;em.opt.B;em.opt.Rdoublechi2ALAL chi-square value (astrometric_chi2_al)stat.fit.chi2doubleNgALNumber of good observations AL (astrometric_n_good_obs_al)meta.numberintE(BR/RP)BP/RP excess factor (phot_bp_rp_excess_factor)phot.color.excessdoublePmembMembership probability (proba)stat.fit.goodnessfloatSimbadSimbad column added by the CDSmeta.ref.urlchar_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.decnullableindexed